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Evidence for Testosterone Influencing Sports Performance

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Back in July I wrote about how there is controversy on whether or not MtF transgenders should compete with ‘bio women’ and whether or not their anthropometry or hormones gave them an advantage over biological women (I am aware that T levels decrease once they go on HRT, just a lot of them still have T ranges in near the low end of the new numbers for men). Well I am reading The Sports Gene by Jerry Epstein and he brings up two (anecdotal) examples of MtF transgenders who take HRT and see a decrease in performance due to decreased T:

No scientist can claim to know the precise impact of testosterone on any individual athlete. But a 2012 study that spent three months following female athletes from a range of sports—including track and field and swimming—showed that elite-level competitors had testosterone levels that consistently remained more than twice as high as those of the nonelites. And there are powerful anecdotes as well.

Joanna Harper, fifty-five, is a medical physicist who was born a male and later transitioned to living as a woman. Harper also happens to be a nationally accomplished age-group runner, and when she started hormone therapy in August 2004 to suppress her body testosterone and physically transition to female [Note from RR: I, of course, do not agree with the use of ‘her’ and that ‘she’ ‘physically transition[ed] to female’] like any good scientist, she took data. Harper figured she would slow down gradually, but was surprised to find herself getting slower and weaker by the end of the first month. “I felt the same when I ran,” she says. “I just couldn’t go  as fast.” In 2012, Harper won the U.S. national cross-country title for the fifty-five-to-fifty-nine age group, but age and gender-graded performance standards indicate that Harper is precisely as competitive now as a female as she was as a male. That is, as a female, Harper is just as good relative to women as she was relative to men before her transition, but she’s far slower than her former, higher-testosterone self.

In 2003, as a man, Harper ran Portland’s Helvetia Half-Marathon in 1:23:11. In 2005, as a woman, she ran the same race in 1:34:01. Harper’s male time was about fifty seconds faster than her female time. She has compiled data from five other runners who have transitioned from male to female, and all show the same pattern of precipitous speed decline. One runner competed in the same 5K for fifteen years straight, eight times as a man and then seven times as a woman following testosterone suppression therapy; always faster than nineteen minutes as a man, and always slower than twenty minutes as a woman. (Epstein, 2013: 78) [Keep in mind that I have the nook version so the physical copy may have this on a different page.

Yes this is anecdotal evidence that testosterone gave an advantage while ‘male’ and then when they ‘transitioned’ to ‘female’ it showed that they became weaker, but still at the top level of women’s performance. Knowing this—how this man had an advantage ‘as a man’ and kept the same relative advantage when he ‘transitioned to a woman’ is a large clue that testosterone does infer an inherent advantage to athletes who have more of the hormone surging through their body.

Testosterone is known to affect skeletal muscle growth, but the mechanisms by which testosterone affects muscle growth are not known (Bhasin, Woodhouse, and Storer, 2001). Also, women with very high androgen levels—whether it’s due to endogenous or exogenous testosterone—have a 2.5 to 5 percent advantage over women who have androgen levels in the normal range (Berman, 2017). So the difference in performance—between women at least—with high and low levels of testosterone is not too great, though that 2.5 to 5 percent advantage most likely would come into play at the very end of the race.

Also recall that I previously wrote that, per the IOC guidelines, a ‘MtF’ needs to ‘declare herself’ a woman for at least four years while taking HRT for 1-2 years to be able to compete with ‘the gender they think they are’. Well, the testosterone levels that the IOC states is ‘OK’ for ‘MtFs’ is still in the low range of the new testosterone guidelines for men! Testosterone most definitely does give an advantage in sports. Think of sports as a modern day test of survival. Basically, those good at sports—such as football and basketball for instance—would have been better able to form hunting parties in our evolutionary past. So while forming these parties, testosterone rose since testosterone raises while men are in groups as well as preparing for competition (Booth et al, 1989). So since our modern body plans sprang up around 2 mya with the appearance of Homo erectus in the fossil record, we can logically infer that cooperation and testosterone—among other things—were needed to be successful hunters.

So if you look at most sports as just a way for men to have a competitive spirit and simulate fighting/hunting with other men, then it makes it clear that testosterone does infer an advantage in sports. For instance, there is a clear relationship between testosterone and explosive jumping (Cardinale and Stone, 2006). These relationships are very clear, have large effects yet bodies like the IOC disregard these findings, allowing MtFs to compete with real women, even when the data and verbal argumentation against letting them compete are logically sound.

Studies do state, of course, that the relationship between high testosterone and athletic performance hasn’t been proven, they also haven’t been refuted either (Sudai, 2017). In fact, all you need to look at is traits that are influenced by testosterone—height, size of limbs, fat mass, shoulder width/size (the most androgen receptors lie in the shoulders and traps muscles, so to tell if someone is juicing, they will have low levels of body fat but ‘3-D delts’ and large traps) etc. So just by looking at a few simple traits and then comparing anatomy with females who have high testosterone compared to women who do not have high levels of testosterone, we can draw the logical conclusion that testosterone does increase sports performance for both men and women, and we have both anecdotal and experimental evidence for the assertion.

In sum, the anecdotal evidence from Epstein’s book is a good start. However, we will need more than anecdotal evidence to prove that testosterone truly does give individuals an advantage if they do have higher testosterone levels than their competition. As larger studies get done, these effects will begin to get teased out. I am certain that testosterone will be found to give a huge advantage in terms of sports, and since sports are a way for us to compete with each other, impress women, gauge other males’ fighting skills, and began as a way to hone skills used to hunt and fight (Lombardo, 2012). Sports began as a way for us to develop the skills needed to survive and hunt, among other things, and so, to hunt, you need to have high levels of testosterone to give that ‘boost’. So if sports began as a way to gauge potential rivals and allies, and as a way to hone/improve fighting skills, then we can logically state that testosterone does give an advantage in sports competition.

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Why Do Jamaicans, Kenyans, and Ethiopians Dominate Running Competitions?

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Much has been written about the genotypic and phenotypic differences in Jamaicans, Kenyans, and Ethiopians. Why do they dominate these competitions? Is it cultural? Genetic? Does training matter more? Grit? Expertise? There are multiple reasons that they have such an advantage, the most important one being their morphology/somatype. Of course other physiologic and morphologic factors come into play for these three populations, but the greatest physical advantage they have is their somatype which lends itself to running—whether short, medium or long distance.

Back in July, I argued that the wide-hipped Neanderthals were stronger than the recently migrated Homo sapiens, due mostly to pelvic anatomy (along with Neanderthal protein intake). That’s one of the keys to explaining African dominance in running: their long slender bodies with high limb ratios.

Kenyans and Ethiopians

Kenyan distance running is driven by an ethny named the Kalenjin, particularly of the Nandi tribe. Much research has been undertaken on the physiology and morphology of certain subpopulations of Kenyans, with a complex genotype, phenotype, and even SES interaction driving the dominance of this subpopulation (Tucker, Onywera, and Santos-Concejero, 2015). Another important factor is their low BMI. Kenyans have the lowest BMIs in the world at 21.5, which considerably helps in regards to distance running (Radovanovic et al, 2014; Shete, Bute, and Deshmukh, 2014Sedeaud et al, 2015).

Kenyans—like Jamaicans and Ethiopians—dominate these competitions due to a complex interaction between genes, environment and SES (Tucker, Onywera, and Santos-Concejero, 2015). Though, of course, a lot of what makes certain Kenyan populations dominate is trainable in other populations. Caucasians can have similar trainability in regards to Vo2 max, oxidative enzymes, and running economy. However, Kenyans are more likely to be slender with longer limbs which is a huge advantage in these competitions. So having a good running economy and a high Vo2 max may be the primary causal factors that cause them to be so good at distance running, with, as I’ve noted in the past, a higher genetic ceiling for high Vo2 max, along with high-altitude training (Larsen, 2003). Though Saltin et al (1995) conclude that physical activity during childhood combined with intense training as a teenager explains the higher Vo2 max in Kenyan boys. Other factors such as low blood lactate and ammonia accumulation are also important.

Genetics, though, is the most likely explanation for African distance-running dominance (Vancini et al, 2014; see Scott and Pitsiladis, 2007 for alternative view that as of yet there are no genetic evidence for African running superiority).

Not all studies show that Kenyans have more slow-twitch (type I) fibers than Caucasians, though the oxygen cost of running at a given velocity was found to be lower in elite Kenyan runners compared to non-Kenyans, which may be due to body dimensions. Apparently, there is no indication that Kenyans possess a pulmonary system that confers a physiologic advantage over non-Kenyans (Larsen and Sheel, 2015). Ethiopian diets, however, met the most recommendations for macronutrients, but fluids were lacking (Beis et al, 2011), similar to what is found on similar studies in Kenyans (Onywera et al, 2003).

It is important to note that not all of the literature out there says that there are mainly physiologic/genetic reasons for their success in distance running; other factors that may be at play are somatype which leads to exceptional biomechanical and metabolic efficiency, high-altitude training, and the want to succeed for economic and social advancement (Wilbur and Pitsiladis, 2012). Oxygen transport of the blood doesn’t explain Kenyan dominance either, they have similar oxygen transport as elite German runners (Prommer et al, 2010). Though, women and men from Ethiopia and Kenya, although they only account for <0.1% of the marathons and half-marathons, achieved the fastest times and were the youngest in the half-marathons and full-marathons (Knechtle et al, 2016). Similar results were seen in Switzerland, with male Africans being faster and younger than non-Africans (Aschmann et al, 2013).

From the years 2000-2014, Knechtle et al (2017) analyzed the Boston, Berlin, New York, and Chicago marathon along with the Stockholm marathon. Over this time period, Ethiopian men improved their times, but Ethiopian women didn’t. Age increased in Ethiopian men, but not women. Female and male marathon runners from Ethiopia were the fastest (Knechtle et al 2017). More studies, though, are needed to unravel the complex relationship between environmental and genetic factors that cause East Africans to dominate distance running (Onywera, 2009). However, elite endurance athletes consistently test higher than non-elite athletes on running economy, Vo2 max, and anaerobic threshold (Lorenz et al, 2013), and mechanical work may be able to predict recreational long distance performance (Tartaruga et al, 2013).

Jamaicans

Jamaican sprinting dominance has been chalked up to numerous factors, most recently, symmetry of the knees and ankles (Trivers, Palestis, and Manning, 2013; Trivers et al, 2014). Trivers et al (2014) write in the Discussion:

Jamaicans are the elite sprinters of the world. Why? If symmetry of knees and ankles is a factor, why should Jamaicans be especially symmetrical (there is no knowledge of whether they actually are)? One possibility is heterozygosity for genes important to sprinting. The slave trade greatly increased heterozygosity on the West African side by mixing genes up and down the West coast of Africa from Senegal to Nigeria [15][16]. Recently a mtDNA haplotype has been isolated that correlates with success in African American–but not Jamaican–sprinters [17]. Since there is a general (if often weak) positive relationship between heterozygosity and body symmetry [18] we are eager to do targeted studies of genomics on areas associated with sprinting, including energy substrate utilization, muscle fibre-type distribution and body composition analyses (with specific reference to the shape and size of the glutei maximi). Fast twitch (anaerobic) muscle fibres are characterized by specific adaptations which benefit the performances of explosive high-intensity actions such as those involved in sprinting. Notably, West Africans appear to have a higher fast twitch muscle fibre content than do comparable Europeans (67.5% vs 59% in one sample [19], as cited in [20]).

It’s interesting to note that the mtDNA haplotype predicts success in African American sprinters, but not Jamaicans. In regards to mtDNA haplotypes, Jamaican sprinters had statistically similar mtDNA haplotypes, which suggests that the elite sprinters arose from the same source population which indicates that there is no population stratification or isolation on sprint performance. African American sprinters and non-sprinters, on the other hand, had statistically significant differences in mtDNA, which implies that maternal ancestry plays a part in sprinting performance (Deason et al, 2011). Studying both maternal and paternal haplotypes to see where source populations originate is important in these fields, since if we know where their population came from, then we can better understand the hows and whys of elite running performance—especially between race. Though demographic studies on Jamaicans show that elite sprinters come from the same demographic population, so genetics cannot possibly account for Jamaican sprinting success, so their sprinting success may be related to environmental and social factors (Irving et al, 2013). We know little about the genomics of elite sporting performance (Pitsiladis et al, 2013), so the physical correlates (somatype) and physiologic correlates will do for now.

Usain Bolt is the current fastest man in the world, due in part to his anthropometric advantage (Krzystof and Mero, 2013). As everyone knows, you cannot teach speed (Lombardo and Deaner, 2014). Bolt himself has a large advantage, in part, to his power development and biomechanical efficiency compared to the people he competes with (Beneke and Taylor, 2010). Though one study has noted that a human may be able to run faster quadrupedally than bipedally–stating that at the 2048 Olympic Games, that the fastest human on the planet may well be a quadrupedal runner (Kinugasa and Usami, 2016). One of the most important factors of acceleration in the 100m sprint is stride frequency (Mackala, Fostiak, and Kowalski, 2015).

In Afro-Caribbean adolescents, body height and stride number to body height ratio were the main determinants of sprint performance (Copaver, Hertogh, and Hue, 2012). Body height being a predictor of sprint performance is nothing new; taller people have longer limbs; longer limbs cover more distance per step. Indeed, sprinters are taller than the American population, there is more variability in men than in women, sprinters have lower body mass and the height range excludes people who are really tall or really short (Uth, 2005).

Fiber typing

I will touch on fiber typing again since I’ve come across new information on it.

East Asians are less likely to have the RR allele of the ‘sprint gene’ (MacArthur and North, 2004) (ACTN3) while Bantus are more likely to have it. Alpha-actinen-3 is a skeletal muscle isoform which is encoded by the ACTN3 gene. Alpha-actinen-3 deficiency is common in the general population (North, 2008; Berman and North, 2010), which means that most people in the general population are XX. Eighteen percent of the population on earth is homozygous for this mutation (Ivarsson and Westerblad, 2015). This allele is the 577X allele, and Bantus are less likely to have it while Eurasians are more likely to have it. The frequency of the RR genotype is also highest in Bantus than in Asians (Mills et al, 2001). This is one very important reason why Eurasians are not faster than Africans (somatype matters too, of course).

Elite sprinters are more likely to be RR and less likely to be XX. Why does this matter? It matters because the RR genotype with the right morphology, fiber type (fast twitch) and contractile properties of the individual fast twitch fibers contribute to heightened performance with an RR genotype (Broos et al, 2016). Jamaicans are also less likely to have the XX genotype (~2 percent) along with Kenyans (Scott et al, 2010). So this shows that since Jamaicans are less likely to be XX, they’re more likely to be RR. So since XX i negatively associated with sprint status, then populations that have a lower frequency will be more likely to have more sprinters, whereas a population that has the genotype will have fewer sprinters.

This is one of many genetic factors that account for elite sprinting performance between populations. So, clearly, the right muscle fiber type combined with the right genotype from the ACTN3 gene infers an advantage, contrary to Daniel MacArthur’s claims that it does not (one of the authors of numerous studies on the ACTN3 gene).

Conclusion

The genetics of sprinting/distance running is currently poorly understood. Though we have a few candidates (and they’re really good, showing variation where they should) like the RR ACTN3 genotype combined with fast twitch fibers. This is very important to note. If you’re missing this, and you’re short with a low Vo2 max and low limb length, there’s an extremely high chance you will not be an elite sprinter/distance runner. I cannot emphasize enough how much the physical factors mean when it comes to this.

It is possible that SES variables combined with other psycho-social factors could explain why these three populations excel so well in these sports. Though, on the other hand, you cannot discount that the individual has to have the right somatype and physical capabilities first. Contrary to popular belief, fiber typing DOES give an advantage, especially if combined with other variables. Low BMI is very important, as are long limbs and a taller than average height.

When it comes to Jamaicans, symmetry of the knees and ankles help considerably, along with a low body mass and taller body. SES factors could be driving the will to compete in these three populations, however, the physical ability needs to be there first, then it needs to be nurtured. Over the next 5 to 10 years, we will have a better understanding of why some populations excel over others and that will largely be due to somatype, physiology, and genetic factors, with SES and other psycho-social factors driving the want to excel in the sport.

The physical differences that underlie the success of these three populations needs more study. Elite athletes of Jamaican, Kenyan, and Ethiopian descent need to be studied more to untangle the physiologic, psychological, physical and social factors that have them excel so well. We know that certain combinations of traits infer a great advantage in certain populations, we now just need enough elite athletes of these populations to study to see how and why they excel so much. The current body of research reviewed here is a good start, though it does leave some questions unanswered.

HBD and Sports: Baseball and Reaction Time

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If you’ve ever played baseball, then you have first-hand experience on what it takes to play the game, one of the major abilities you need is a quick reaction time. Baseball players are in the upper echelons in regards to pitch recognition and ability to process information (Clark et al, 2012).

Some people, however, believe that there is an ‘IQ cutoff’ in regards to baseball; since general intelligence is supposedly correlated with reaction time (RT), then those with higher RTs must have higher intelligence and vice-versa. However, this trait—in a baseball context—is trainable to an extent. To those that would claim that IQ would be a meaningful metric in baseball I pose two question: would higher IQ teams, on average, beat lower IQ teams and would higher IQ people have better batting averages (BAs) than lower IQ people? This, I doubt, because as I will cover, these variables are trainable and therefore talking about reaction time in the MLB in regards to intelligence is useless.

Meden et al (2012) tested athlete and non-athlete college students on visual reaction time (VRT). They tested the athletes’ VRT once, while they tested the non-athletes VRT two times a week for a 3 week period totaling 6 tests. Men ended up having higher VRTs in comparison to women, and athletes had better VRTs than non-athletes. So therefore, this study proves that VRT is a trainable variable. If VRT can be improved with training, then hitting and fielding can also be trained as well.

Reaction time training is the communication between the brain, musculoskeletal system and spinal cord, which includes both physical and cognitive training. So since VRT can be trained, then it makes logical sense that Major League hitting and fielding can be trained as well.

David Epstein, author of The Sports Gene says that he has a faster reaction time than Albert Pujols:

One of the big surprises for me was that pro athletes, particularly in baseball, don’t have faster reflexes on average than normal people do. I tested faster than Albert Pujols on a visual reaction test. He only finished in the 66thpercentile compared to a bunch of college students.

It’s not a superior RT that baseball players have in comparison to the normal population, says Epstein, but “learned perceptual skills that the MLB players don’t know they learned.” Major League baseball players do have average reaction times (Epstein, 2013: 1) but a far superior visual acuity. Most pro-baseball players had visual acuity of 20/13, with some players having 20/11; the theoretical best visual acuity that is possible is 20/8 (Clark et al, 2012). Laby, Kirschen, and Abbatine show that 81 percent of the 1500 Major and Minor League Mets and Dodgers players had visual acuities of 20/15 or better, along with 2 percent of players having a visual acuity of 20/9.2. Baseball players average a 20/13 visual acuity with the best eyesight humanly possible being 20/8. (Laby et al, 1996).

So it’s not faster RT that baseball players have, but a better visual acuity—on average—in comparison to the general population. Visual reaction time is a highly trainable variable, and so since MLB players have countless hours of practice, they will, of course, be superior on that variable.

Clark et al (2012) showed that high-performance vision training can be performed at the beginning of the season and maintained throughout the season to improve batting parameters. They also state that visual training programs can help hitters, since the eyes account for 80 percent of the information taken into the brain. Reichow, Garchow, and Baird (2011) conclude that a “superior ability to recognize pitches presented via tachistoscope may correlate with a higher skill level in batting.” Clark et al (2012) posit that their training program will help batters to better recognize the spot of the ball and the pitcher’s finger position in order to better identify different pitches. Clark et al (2012) conclude:

The University of Cincinnati baseball team, coaches and vision performance team have concluded that our vision training program had positive benefits in the offensive game including batting and may be providing improved play on defense as well. Vision training is becoming part of out pre-season and in season conditioning program as well as for warmups.

Classe et al (1997) showed that VRT was related to batting, but not fielding or pitching skill. Further, there was no statistically significant difference observed between VRT and age, race or fielding. Therefore, we can say that VRT has no statistical difference on race and does not contribute to any racial differences in baseball.

Baseball and basketball athletes had faster RTs than non-athletes (Nakamoto and Mori, 2008). The Go/NoGo response that is typical of athletes is most certainly trainable. Kida et al (2005) showed that intensive practice improved the Go/NoGo reaction time, but not simple reaction time. Kida et al (2005: 263-264) conclude that simple reaction time is not an accurate indicator of experience, performance or success in sports; Go/NoGo can be improved by practice and is not innate (but simple reaction time was not altered) and the Go/NoGo reaction time can be “theoretically shortened toward a certain value determined by the simple reaction time proper to each individual.

In baseball players in comparison to a control group, readiness potential was significantly shorter for the baseball players (Park, Fairweather, and Donaldson, 2015).  Hand-eye coordination, however, had no effect on earned run average (ERA) or batting average in a sample of 410 Major and Minor League members of the LA Dodgers (Laby et al, 1997).

So now we know that VRT can be trained, VRT shows no significant racial differences, and that Go/NoGo RT can be improved by practice. Now a question I will tackle is: can RT tell us anything about success in baseball and is RT related to intelligence/IQ?

Khodadi et al (2014) conclude that “The relationship between reaction time and IQ is too complicated and revealing a significant correlation depends on various variables (e.g. methodology, data analysis, instrument etc.).” So since the relationship is too complicated between the two variables, mostly due to methodology and the instrument used, RT is not a good correlate of IQ. It can, furthermore, be trained (Dye, Green, and Bavelier, 2012).

In the book A Question of Intelligence, journalist Dan Seligman writes:

In response, Jensen made two points: (1) The skills I was describing involve a lot more than just reaction time, they also depended heavily on physcial coordination and endless practice. (2) It was, however, undoubtedly true that there was some IQ requirement-Jensen guessed it might be around 85- below which you could never recruit for major league baseball. (About one-sixth of Americans fall below 85).

I don’t know where Jensen grabbed the ‘IQ requirement’ for baseball, which he claims to be around 85 (which is at the black average in America). This quote, however, proves my point that there is way more than RT involved in hitting a baseball, especially a Major League fastball:

Hitting a baseball traveling at 100 mph is often considered one of the most difficult tasks in all of sports. After all, if you hit the ball only 30% of the time, baseball teams will pay you millions of dollars to play for them. Pitches traveling at 100 mph take just 400 ms to travel from the pitcher to the hitter. Since the typical reaction time is 200 ms, and it takes 100 ms to swing the bat, this leaves just 100 ms of observation time on which the hitter can base his swing.

This lends more credence to the claim that hitting a baseball is more than just quick reflexes; considerable training can be done to learn certain cues that certain pitchers use; for instance, like identifying different pitches a particular pitcher does with certain arm motions coming out of the stretch. This, as shown above in the Epstein quote, is most definitely a trainable variable.

Babe Ruth, for instance, had better hand-eye coordination than 98.8 percent of the population. Though that wasn’t why he was one of the greatest hitters of all time; it’s because he mastered all of the other variables in regards to hitting, which are learnable and not innate.

Witt and Proffitt (2005) showed that the apparent ball size is correlated with batting average, that is, the better batters fared at the plate, the bigger they perceived the ball to be so they had an easier time hitting it. Hitting has much less to do with reaction time and much more to do with prediction, as well as the pitching style of the pitcher, his pitching repertoire, and numerous other factors.

It takes a 90-95 mph fast ball about 400 milliseconds to reach home plate. It takes the brain 100 milliseconds to process the image that the eyes are taking in, 150 milliseconds to swing and 25 milliseconds for his brain to send a signal to his body to swing. This leaves the hitter with 125 milliseconds left to hit the incoming fastball. Clearly, there is more to hitting than reaction time, especially when all of these variables are in play. Players have .17 seconds to decide whether or not to hit a pitch and where to place their bat (Clark et al, 2012)

A so-called ‘IQ cutoff’ for baseball does exist, but only because IQs lower than 85 (once you begin to hit the 70s range, especially the lower levels) indicate developmental disorders. Further, the 85-115 IQ range encompasses 68 percent of the population. However, RT is not even one of the most important factors in hitting; numerous other (trainable) variables influence fastball hitting, and all of the best players in the world employ these strategies. People may assume that since intelligence and RT are (supposedly) linked, that baseball players, since they (supposedly) have quick RTs. Nevertheless, if quick RTs were correlated with baseball profienciency—namely, in hitting, then why are Asians 1.2 percent of the players in the MLB? Maybe because RT doesn’t really have anything to do with hitting proficiency and other variables have more to do with it.

People may assume that since intelligence and RT are (supposedly) linked, that baseball players, since they (supposedly) have quick RTs then they must be intelligent and therefore there must be an IQ cutoff because intelligence/g and RT supposedly correlate. However, I’ve shown 2 things: 1) RT isn’t too important to hitting at an elite level and 2) more important skills can be acquired in hitting fastballs, most notable, in my opinion, is pitch verification and the arm location of the pitcher. The Go/NoGo RT can also be trained and is, arguably, one of the most important training systems for elite hitting. Clearly, elite hitting is predicated on way more than just a quick RT; and most of the variables that are involved in elite hitting are most definitely trainable, as reviewed in this article.

People, clearly, make unfounded claims without having any experience in something. It’s easy to make claims about something when you’re just looking at numbers and attempting to draw conclusions based on data. But it’s a whole other ballgame (pun intended) when you’re up at the plate yourself or coaching someone on how to hit or play in the infield. These baseless claims would be avoided a lot more if only the people who make these claims had any actual athletic experience. If so, they would know of the constant repetition that goes into hitting and fielding, the monotonous drills you have to do everyday until your muscle memory is trained to flawlessly—without even thinking about it—throw a ball from shortstop to first base.

Practice, especially Major League practice, is pivotal to elite hitting; only with elite practice can a player learn how to spot the ball and the pitcher’s finger position to quickly identify the pitch type in order to decide if he wants to swing or not. In conclusion, a whole slew of cognitive/psychological abilities are involved in the upper echelons of elite baseball, however a good majority of the traits needed to succeed in baseball are trainable, and RT has little to do with elite hitting.

(When I get time I’m going to do a similar analysis like what I wrote about in the article on my possible retraction of my HBD and baseball article. Blacks dominate in all categories that matter, this holds for non-Hispanic whites and blacks as well as Hispanic blacks and whites, read more here. Nevertheless, I may look at the years 1997-2017 and see if anything has changed from the analysis done in the late 80s. Any commentary on that matter is more than welcome.)

Racial Differences in Jock Behavior: Implications for STI Prevalence and Deviance

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The Merriam-Webster dictionary defines jock asa school or college athlete” and “a person devoted to a single pursuit or interest“. This term, as I previously wrote about, holds a lot of predictive power in terms of life success. What kind of racial differences can be found here? Like with a lot of life outcomes/predictors, there are racial differences and they are robust.

Male jocks get more sex, after controlling for age, race, SES and family cohesion. Being involved in sports is known to decrease sexual promiscuity, however, this effect did not hold for black American jocks, with the jock label being associated with higher levels of sexual promiscuity (Miller et al, 2005). Black American jocks reported significantly higher levels of sexual activity than non-black jocks, but they did not find that white jocks too fewer risks than their non-jock counterparts.

Black Americans do have a higher rate of STDs compathe average population (Laumann et al, 1999Cavanaugh et al, 2010; CDC, 2015). Black females who are enrolled in, or have graduated from college had a higher STI (sexually transmitted infection) rate (12.4 percent self-reported; 13.4 percent assayed) than white women with less than a high school diploma (6.4 percent self-reported; 2.3 percent assayed) (Annang et al, 2010). I would assume that these black women would be more attracted to black male jocks and thusly would be more likely to acquire STIs since black males who self-identify as jocks are more sexually promiscuous. It seems that since black male jocks—both in high school and college—are more likely to be sexually promiscuous, this then has an effect on even the college-educated black females, since higher educational status has one less likely to acquire STIs.

Whites use the ‘jock identity’ in a sports context whereas blacks use the identity in terms of the body. Black jocks are more promiscuous and have more sex than white jocks, and I’d bet that black jocks have more STDs than white jocks since they are more likely to have sex than white jocks. Jock identity—but not athletic activity and school athlete status—was a better predictor of juvenile delinquency in a sample of 600 Western New York students, which was robust across gender and race (Miller et al, 2007a). Though, surprisingly, the ‘jock effect’ on crime was not as you would expect it: “The hypothesis that effects would be stronger for black adolescents than for their white counterparts, derived from the work of Stark et al. 1987 and Hughes and Coakley (1991), was not supported. In fact, the only clear race difference that did emerge showed a stronger effect of jock identity on major deviance for whites than for blacks” (Miller et al, 2007a).

Miller et al (2007b) found that the term jock means something different to black and white athletes. For whites, the term was associated with athletic ability and competition, whereas for blacks the term was associated with physical qualities. Whites, though, were more likely to self-identify with the label of jock than blacks (37 percent and 22 percent respectively). They also found that binge drinking predicted violence amongst family members, but in non-jocks only. The jock identity, for whites and not blacks, was also associated with more non-family violence while whites were more likely to use the aggression from sports in a non-sport context in comparison to blacks.

For black American boys, the jock label was a predictor of promiscuity but not for dating. For white American jocks, dating meant more than the jock label. Miller et al (2005) write:

We suggest that White male jocks may be more likely to be involved in a range of extracurricular status-building activities that translate into greater popularity overall, as indicated by more frequent dating; whereas African American male jocks may be “jocks” in a more narrow sense that does not translate as directly into overall dating popularity. Furthermore, it may be that White teens interpret being a “jock” in a sport context, whereas African American teens see it more in terms of relation to body (being strong, fit, or able to handle oneself physically). If so, then for Whites, being a jock would involve a degree of commitment to the “jock” risk-taking ethos, but also a degree of commitment to the conventionally approved norms with sanctioned sports involvement; whereas for African Americans, the latter commitment need not be adjunct to a jock identity.

It’s interesting to speculate on why whites would be more prone to risk-taking behavior than blacks. I would guess that it has something to do with their perception of themselves as athletes, leading to more aggressive behavior. Though certain personalities would be more likely to be athletic and thusly refer to themselves as a jock. The same would hold true for somatype as well.

So the term jock seems to mean different things for whites and blacks, and for whites, leads to more aggressive behavior in a non-sport context.

Black and females who self-identified as jocks reported lower grades whereas white females who self-identified as jocks reported higher grades than white females who did not self-report as jocks (Miller et al, 2006). Jocks also reported more misconduct such as skipping school, cutting class, being sent to the principals office, and parents having to go to the school for a disciplinary manner compared to non-jocks. Boys were more likely to engage in actions that required disciplinary intervention in comparison to girls, while boys were also more likely to skip school, have someone called from home and be sent to the principal’s office. Blacks, of course, reported lower grades than whites but there was no significant difference in misconduct by race. However, blacks reported fewer absences but more disciplinary action than whites, while blacks were less likely to cut class, but more likely to have someone called from home and slightly more likely to be sent to the principal’s office (Miller et al, 2006).

This study shows that the relationship between athletic ability and good outcomes is not as robust as believed. Athletes and jocks are also different; athletes are held in high regard in the eyes of the general public while jocks are seen as dumb and slow while also only being good at a particular sport and nothing else. Miller et al (2006) also state that this so-called ‘toxic jock effect‘ (Miller, 2009Miller, 2011) is strongest for white boys. Some of these ‘effects’ are binge drinking and heavy drinking, bullying and violence, and sexual risk-taking. Though Miller et al (2006) say that, for this sample at least, “It may be that where academic performance is concerned, the jock label constitutes less of a departure from the norm for white boys than it does for female or black adolescents, thus weakening its negative impact on their educational outcomes.

The correlation between athletic ability and jock identity was only .31, but significant for whites and not blacks (Miller et al, 2007b). They also found, contrary to other studies, that involvement in athletic programs did not deter minor and major adolescent crime. They also falsified the hypothesis that the ‘toxic jock effect’ (Miller, 2009; Miller, 2011) would be stronger for blacks than whites, since whites who self-identified as jocks were more likely to engage in delinquent behavior.

In sum, there are racial differences in ‘jock’ behavior, with blacks being more likely to be promiscuous while whites are more likely to engage in deviant behavior. Black women are more likely to have higher rates of STIs, and part of the reason is sexual activity with black males who self-identify as jocks, as they are more promiscuous than non-jocks. This could explain part of the difference in STI acquisition between blacks and whites. Miller et al argue to discontinue the use of the term ‘jock’ and they believe that if this occurs, deviant behavior will be curbed in white male populations that refer to themselves as ‘jocks’. I don’t know if that will be the case, but I don’t think there should be ‘word policing’, since people will end up using the term more anyway. Nevertheless, there are differences between race in terms of those that self-identify as jocks which will be explored more in the future.

Nerds vs. Jocks: Different Life History Strategies?

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I was alerted to a NEEPS (Northeastern Evolutionary Psychology Society) conference paper, and one of the short abstracts of a talk had a bit about ‘nerds’, ‘jocks’, and differing life history strategies. Surprisingly, the results did not line up with current stereotypes about life outcomes for the two groups.

The Life History of the Nerd and Jock: Reproductive Implications of High School Labels

The present research sought to explore whether labels such as “nerd” and “jock” represent different life history strategies. We hypothesized that self-identified nerds would seek to maximize future reproductive success while the jock strategy would be aimed at maximizing current reproductive success. We also empirically tested Belsky’s (1997) theory of attachment style and life history. A mixed student/community sample was used (n=312, average age = 31) and completed multiple questionnaires on Survey Monkey. Dispelling stereotypes, nerds in high school had a lower income and did not demonstrate a future orientation in regards to reproductive success, although they did have less offspring. Being a jock in high school was related to a more secure attachment style, higher income, and higher perceived dominance. (NEEPS, 2017: 11)

This goes against all conventional wisdom; how could ‘jocks’ have better life outcomes than ‘nerds’, if the stereotype about the blubbering idiot jock is supposedly true?

Future orientation is The degree to which a collectivity encourages and rewards future-oriented behaviors such as planning and delaying gratification (House et al, 2004,p. 282). So the fact that self-reported nerds did not show future orientation in regards to reproductive success is a blow to some hypotheses, yet they did have fewer children.

However, there are other possibilities that could explain why so-called nerds have fewer children, for instance, they could be seen as less attractive and desirable; could be seen as anti-social due to being, more often than not, introverted; or they could just be focusing on other things, and not worrying about procreating/talking to women so they end up have fewer children as result. Nevertheless, the fact that nerds ended up having lower income than jocks is pretty telling (and obvious).

There are, of course, numerous reasons why a student should join a sport. One of the biggest is that the skills that are taught in team sports are most definitely translatable to the real world. Most notably, one who plays sports in high school may be a better leader and command attention in a room, and this would then translate over to success in the post-college/high school world. The results of this aren’t too shocking—to people who don’t have any biases, anyway.

Why may nerds in high school have had lower income in adulthood? One reason could be that the social awkwardness did not translate into dollar signs after high school/college graduation, or chose a bad major, or just didn’t know how to translate their thoughts into real-world success. Athletes, on the other hand, have the confidence that comes from playing sports and they know how to work together with others as a cohesive unit in comparison to nerds, who are more introverted and shy away from being around a lot of people.

Nevertheless, this flew in the faces of the stereotypes of nerds having greater success after college while the jocks—who (supposedly) don’t have anything beyond their so-called ‘primitive’ athletic ability—had greater success and more money. This flies in the face of what others have written in the past about how nerds don’t have greater success relative to the average population, well this new presentation says otherwise. Thinking about the traits that jocks have in comparison to nerds, it doesn’t seem so weird that jocks would have greater life outcomes in comparison to nerds.

Self-reported nerds, clearly, don’t don’t have the confidence to make the stratospheric amounts of cash that people would assume that they should make because they are knowledgeable in a few areas, on the contrary. Those who could use their body’s athletic ability had more children as well as had greater life success than nerds, which of course flew in the face of stereotypes. Certain stereotypes need to go, because sometimes stereotypes do not tell the truth about some things; it’s just what people believe ‘sounds good’ in their head.

If you think about what it would take, on average, to make more money and have great success in life after high school and college, you’ll need to know how to talk to people and how to network, which the jocks would know how to do. Nerds, on the other hand, who are more ‘socially isolated’ due to their introverted personality, would not know too much about how to network and how to work together with a team as a cohesive unit. This, in my opinion, is one reason why this was noticed in this sample. You need to know how to talk to people in social settings and nerds wouldn’t have that ability—relative to jocks anyway.

Jocks, of course, would have higher perceived dominance since athletes have higher levels of testosterone both at rest and exhaustion (Cinar et al, 2009). Athletes, of course, would have higher levels of testosterone since 1) testosterone levels rise during conflict (which is all sports really are, simulated conflict) and 2) dominant behavior increases testosterone levels (Booth et al, 2006). So it’s not out of the ordinary that jocks were seen as more dominant than their meek counterparts. In these types of situations, higher levels of testosterone are needed to help prime the body for what it believes is going to occur—competition. Coupled with the fact that jocks are constantly in situations where dominance is required; engage in more physical activity than the average person; and need to keep their diet on point in order to maximize athletic performance, it’s no surprise that jocks showed higher dominance, as they do everything right to keep testosterone levels as high as possible for as long as possible.

I hope there are videos of these presentations because they all seem pretty interesting, but I’m most interested in locating the video for this specific one. I will update on this if/when I find a video for this (and the other presentations listed). It seems that these labels do have ‘differing life history strategies’, and, despite what others have argued in the past about nerds having greater success than jocks, the nerds get the short end of the stick.

The Evolution of Racial Pelvis Variation

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It’s well-known that blacks have narrower hips than whites (Rushton, 1997; Handa et al, 2008). These pelvic differences then account for part of the variation in elite sporting events such as sprinting and jumping (Entine, 2000). These pelvic differences are the result of climatic variation and sexual selection.

The evolution of the pelvis is due to bipedalism. We are bipeds because of our S-shaped spine, which helps us to cope with differing loads. The human pelvis had to evolve in two ways—to make birthing babies easier and to become more efficient for bipedal walking. Termed the ‘obstetric dilemma’, it has implications for osteoarthritis in both men and women (Hogervorst, Heinse, and de Vos, 2009). Having a more efficient bipedal gait meant the body could allocate energy to other parts of the body—mainly our growing brains/neuronal count. Over time, the brain grew while the pelvis had to shrink for more efficient bipedalism. The pelvis also got narrower in our evolution, being wider in Australopithicenes, while becoming more narrow when erectus appeared—which is the first instance of a humanlike pelvis in the fossil record—which increased how far we could travel as well as reduce our energy expenditure (Lieberman, et al, 2006). Further discussion can be found in my article Man the Athlete.

So we began evolving a narrower pelvis in comparison to our ancestors because it was more efficient for heat dissipation. Smaller trunks are more efficient for heat dissipation (Lieberman, 2015), whereas wider trunks are more efficient for thermoregulation in colder climes (Weaver and Hublin, 2008; Weaver, 2009; Gruss and Schmidt, 2015). Now, simply applying this logic to Eurasians and Africans (I am grouping East Asians and Europeans together since they were a single breeding population up until about 23,000-6,500ya), we can see one reason why that population has wider pelves than Africans.

When anatomically modern humans (AMH) left Africa between 50-100kya, human skeletal morphology was just like modern-day Africans’ today. When Man migrated into northerly climes, however, a wider pelvis was needed to retain heat in colder climes (Gruss and Schmidt, 2015). So, along with a wider pelvis evolving due to climatic demands on the body, as we migrated north the human brain expanded due to the climate of the area, along with expanding the pelvis to better thermoregulate (which a bigger brain also does in northerly climes). I did argue two months back (and added to Skoyles’ (1999) theory) that brain size increased for expertise capacity and not IQ since Arctic people needed more tools, as well as tools that were more complex, in comparison to peoples who evolved in a hotter climate. So selection then occurred for larger brains and pelvis due to the demand for thermoregulation and bigger brains—which then led to earlier births and more helpless babes, which higher levels of intelligence were then needed to care for them (Piantadosi and Kidd, 2016). The helplessness of infants predicts the intelligence of adults in the primate genera (Piantadosi and Kidd, 2016), so I will assume that this holds within primate species as well (I am not able to locate a citation that this doesn’t hold within the primate genera; if I am in error, please provide a citation). Since African children are born earlier and  more mature than Eurasian children who are born slightly later and more helpless/less developed, this is one reason why Eurasians have higher levels of intelligence than Africans (which is independent of any direct effects of climate I may add!).

So since Eurasians needed a larger brains to make more tools in the Arctic/colder climes, their brains needed to expand in size for increased expertise capacity, which would then have further selected for wider pelves in Eurasian women. Climatic variation caused the wider hips/bigger brains in Eurasians, which then allowed the evolution of larger brains in comparison to those who remained in Africa.

Finally, the obstetric dilemma has been recently called into question; there is evidence that a wider pelvis does not increase locomotor costs in humans (Warrener et al, 2015), a treadmill tracked their gait, as well as the motion of their pelvis. This study is used as evidence that the obstetric dilemma is wrong—they argue that there is no trade-off between narrower hips in men and wider hips in women.  However, as the authors point out, all subjects in the study walked/ran at the same speed. Let’s say that the speed was heightened; do you think the women/men with wider pelves would have had the same locomotor costs as the men/women with narrower pelves? The answer is, obviously, no.

The pelvis of all of the races of Man has evolved the way they are due to environmental/climatic demands. A wider pelvis is better for thermoregulation in colder climates, while a narrower pelvis/body is more efficient for heat loss (Gruss and Schmidt, 2015).

Thus, we can look at the evolution of brain size/pelvic size in a few ways: 1) The amount of tools/complexity of the tools in the area that led to a need for an increase in brain size for more ‘chunks’ (Gobet and Simon, 1998), which then—along with colder climates—selected for larger brains and a wider body/pelvis which made birthing babes with large heads/brains easier along with helping to conserve heat due to the wider body (Gruss and Schmidt, 2015); 2) Since people in higher altitudes needed a high amount of expertise to survive, further selection for bigger brains, wider pelves occurred because of this; 3) Africans have smaller pelves in comparison to Eurasians because they evolved in hotter climes and didn’t have the amount of tools that peoples in more northerly climes did—which also increased brain size; 4) putting this all together, we can say that because Africans live in hotter climates, they need narrow pelves in order to lose body heat; Eurasians, after they migrated into more northerly climes, needed a wider body/pelvis in order to retain heat. When Man migrated north, he needed the ability to become an expert in, say, tool-making and thus needed a bigger brain for more informational chunks (Simon and Gobet, 1998; Skoyles, 1999). Due to this, Eurasians have wider pelves since they needed larger brains for a higher expertise capacity (Skoyles, 1999).

When Man migrated north, he needed the ability to become an expert in, say, tool-making and thus needed a bigger brain for more informational chunks (Simon and Gobet, 1998; Skoyles, 1999). Due to this, Eurasians have wider pelves than Africans; so they can birth larger-brained children. The width of the female pelvis, too, was shaped by sexual selection (Lassek and Gaulin, 2009). Therefore, the evolution of the modern pelvis in human populations comes down to climatic variation, which, in turn, affects how large of a brain the babe is able to have. Climate constrains brain size in either ‘direction’, big or small. We don’t even need to look at the variation within modern Homo sapiens to see the pattern in pelvic size we do today; because the pelvic differences noted among Man definitely were in effect millions of years ago, with hominids in colder climates having wider pelves while hominids in warmer climates had narrower pelves.

Along with everything above, the evolution of the human pelvis has a few implications for the human races today. Some recent studies have shown that there is no obstetric dilemma at all, with birth complications being caused by babies with higher weights than in our ancestral past, due to environmental mismatches causing higher-weight babies (Warrener et al, 2015; Betti, 2017), which was also beneficial for the evolution of our large brains (Cunnane and Crawford, 2003) with the largest amount of cortical neurons in the animal kingdom. However, marked differences in locomotion would be seen in people who had wide pelves compared to narrow pelves; which is what we see in elite running competitions: the elite runners have narrower pelves. So wider pelves don’t impede normal bipedal walking, but it does impede being able to efficiently run, as evidenced in participants of elite sprinting and marathon competitions. Looking at champion athletes and studying their locomotion (along with other traits as I’ve covered here) you can see that those with narrower pelves win more competitions than those with wider pelves (and happen to have different muscle fiber competition, fat distribution/percent, and morphology).

Racial differences in the pelvis explain the reasons behind why a certain race dominates in certain elite competitions; it largely comes down to skeletal morphology. These skeletal differences have evolutionary underpinnings, with the same pelvic differences seen in hominins that evolved in colder/warmer climates in the past. These pelvic differences (along with body fat percentage/distribution, musculoskeletal morphology, muscle fiber type, lean mass percentage, lower Vo2 max, poorer running economy, a larger Q-angle [4.6 degrees greater than men], etc) are why women are less efficient runners. People with wider hips are more likely to have be endomorphic while people with narrower hips are more likely to be ecto and meso. Not surprisingly, people from northerly climes consistently win WSM competitions whereas East and West Africans dominate bodybuilding and sprinting/marathons due to having a narrower pelvis and other advantageous morphological traits that lead to success in the sport. Nevertheless, pelvic differences between the races largely come down to differences in climate, which was also seen in ancient hominins. These pelvic differences further lead to racial differences in elite sporting competition.

References

Betti, L. (2017). Human Variation in Pelvic Shape and the Effects of Climate and Past Population History. The Anatomical Record,300(4), 687-697. doi:10.1002/ar.23542

Cunnane, S. C., & Crawford, M. A. (2003). Survival of the fattest: fat babies were the key to evolution of the large human brain. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology,136(1), 17-26. doi:10.1016/s1095-6433(03)00048-5

Dr. John R. Skoyles (1999) HUMAN EVOLUTION EXPANDED BRAINS TO INCREASE EXPERTISE CAPACITY, NOT IQ. Psycoloquy: 10(002) brain expertise

Entine, J. (2000). Taboo: why Black athletes dominate sports and why we are afraid to talk about it. New York: PublicAffairs.

Gobet, F., & Simon, H. A. (1998). Expert Chess Memory: Revisiting the Chunking Hypothesis. Memory,6(3), 225-255. doi:10.1080/741942359

Gruss, L. T., & Schmitt, D. (2015). The evolution of the human pelvis: changing adaptations to bipedalism, obstetrics and thermoregulation. Philosophical Transactions of the Royal Society B: Biological Sciences,370(1663), 20140063-20140063. doi:10.1098/rstb.2014.0063

Hogervorst, T., Heinse W.B., & de Vos J., (2009) Evolution of the hip and pelvis. Acta Orthopaedica, 80:sup336, 1-39, DOI: 10.1080/17453690610046620

Lieberman, D. E., Raichlen, D. A., Pontzer, H., Bramble, D. M., & Cutright-Smith, E. (2006). The human gluteus maximus and its role in running. Journal of Experimental Biology,209(11), 2143-2155. doi:10.1242/jeb.02255

Lieberman, D. E. (2015). Human Locomotion and Heat Loss: An Evolutionary Perspective. Comprehensive Physiology, 99-117. doi:10.1002/cphy.c140011

Piantadosi, S. T., & Kidd, C. (2016). Extraordinary intelligence and the care of infants. Proceedings of the National Academy of Sciences,113(25), 6874-6879. doi:10.1073/pnas.1506752113

Rushton J P (1997). Race, Evolution, and Behavior. A Life History Perspective (Transaction, New Brunswick, London).

Handa, V. L., Lockhart, M. E., Fielding, J. R., Bradley, C. S., Brubakery, L., Cundiffy, G. W., … Richter, H. E. (2008). Racial Differences in Pelvic Anatomy by Magnetic Resonance Imaging. Obstetrics and Gynecology, 111(4), 914–920.

Warrener, A. G., Lewton, K. L., Pontzer, H., & Lieberman, D. E. (2015). A Wider Pelvis Does Not Increase Locomotor Cost in Humans, with Implications for the Evolution of Childbirth. PLoS ONE, 10(3), e0118903.

Weaver, T. D., & Hublin, J. (2009). Neandertal birth canal shape and the evolution of human childbirth. Proceedings of the National Academy of Sciences,106(20), 8151-8156. doi:10.1073/pnas.0812554106

Weaver, T. D. (2009). The meaning of Neandertal skeletal morphology. Proceedings of the National Academy of Sciences,106(38), 16028-16033. doi:10.1073/pnas.0903864106

The “N” Word

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Numerous academics have been looked at as pariahs for uttering this word. This word has a pretty long history offending people. The word I’m talking about is natural. This “N” word—especially today—is extremely divisive in today’s society. If you say that something is ‘natural‘, are you taking away any accomplishments that one has done, all because it’s ‘natural‘?

Take what I’ve been writing about for the past three weeks: athletics. If you say that one is a “natural” at athletic competition, are you taking away the hard work it took for that specific athlete to accomplish his goal? No way. You’re acknowledging that that specific individual has something special that sets him apart from the average person. That’s not to say that hard work, determination, and confidence don’t matter; on the contrary. They DO matter. However, like I said with the Kalenjin Kenyan distance runners (who do have anatomical/physiologic advantages in regards to sprinting): you can take someone with elite genetics who has done elite training and put him up against someone who has subpar genetics (in terms of the athletic event) with elite training—the same training as the athlete with elite genetics—and the athlete with elite genetics/muscle fibers/physiology will constantly blow away the individual who is less genetically gifted.

People readily admit that certain races excel at certain physical activities whereas other races don’t fare as well. As I’ve extensively covered (and provided more than enough evidence/arguments for), the races differ in the number of muscle fibers which cause higher rates of obesity in blacks; this causes strength differences which then correlate with mortality. Finally, somatype is extremely important when speaking about athletics. Blacks have a mesomorphic somatype, which, along with their fiber typing and physiologic differences on average compared to whites, cause blacks to dominate most sporting events. However, when you say that certain races are “naturally more intelligent than others“, people all of a sudden have a bone to pick.

This “N” word when it comes to athletics is perfectly fine to use in our vocabulary, yet when we begin talking about intelligence differences—between races and individuals—all of a sudden we think that everyone is the same and that all brains are made the same. We believe that, although humans evolved genetically isolated for thousands of years and have incurred anatomic/physiologic differences, that one organ—the brain—is somehow exempt from the forces of natural selection. I can think of no traits that WON’T get selected for/against, and so I can think of no reason why the brain wouldn’t be under different selective pressures in Siberia/Northern Europe/the Americas/Africa/PNG/Australia.

However, as far as I can tell, we have not found any alleles that differ between populations. It was proposed in 2005 that the genes ASPM and Microcephalin influenced brain growth (Evans et al, 2005; Mekel-Brobov et al, 2005). However, two years later, Rushton, Vernon and Ann Bons (2007) showed that there was no evidence that Microcephalin and ASPM were associated with general mental ability (GMA), head circumference or altruism. Peter Frost cites Woodley et al, (2014) showing that the correlation between microcephalin and IQ is .79, whereas the correlation with ASPM and IQ was .254. Woodley et al (2014) also show there is a correlation between Disability Adjusted Life Years (DALY) and Microcephalin. The reasoning is that Microcephalin may improve the body’s immune response to viral infections, enabling humans to live in larger societies and thus get selected for higher IQ. Since the allele seems to give better disease resistance, then, over time, selection for higher intelligence can be selected for since fewer people are dying from disease due to increased resistance.

Nevertheless, the debate is still out on this allele. However, the data does look good in that we may have found certain polymorphisms that differ between populations which may explain some racial differences in intelligence. (For more information on IQ alleles, see Race and IQ: the Case for Genes).

Now, we are beginning to have some good evidence pile up showing that there are population differences in these alleles, and that they do predict intelligence. Racial differences in intelligence aren’t accepted by mainstream science and the public at large (obviously) like physiologic/anatomic differences are between human populations. Populations are split for thousands of years. They evolve different anatomy/physiology based on the environment. So, then, why wouldn’t psychological differences appear between the races of Man, when other, physical changes occurred from the OoA migration? It literally makes no sense.

People readily admit that athleticism is largely “natural“, yet when someone says that differences in intelligence are largely due to genes they get shouted down and called a ‘racist’, as if that adds anything to the dialogue. People readily admit that individuals/races are “naturally” leaner/stronger/faster/have quicker reflexes. But if one just even hints at thinking about “natural” differences between populations when it comes to general mental ability, they will be shouted down and their careers will be ruined.

Why? Why are people so scared of the “N” word? Because people want to believe that what they do or do not accomplish comes down to them as an individual and only them. They don’t want to think about the complex interaction between genes x environment and how that shapes an individual’s life path. They only think about environment, and not any possible genetic factors. Certain people—mostly social science majors—deny that evolution had ANY impact on human behavior. The “N” word, especially in today’s society, is a completely divisive word. State that you hold hereditarian views (in terms of mental ability) in regards to differences between populations and athletic events and no one will bat an eye.

“Didn’t you see Usain Bolt blow away the competition and set a new world record in the 100m dash at 9.58 seconds?!”

“He’s naturally good, he was born a gifted athlete.”

No one will bat an eye if you say this. This is where the tables will be flipped if you say:

“Don’t you know that differences in intelligence are largely genetic in nature and no matter how much you ‘train the brain’ you’ll stay at that intelligence level?”

“Man, that’s racist. That shouldn’t be looked at. We are all the same and equal. Except when it comes to certain athletic events, then we are not equal and some populations have natural predispositions that help them win. Evolution stopped at the neck 100kya; the only parts of the body under selective pressure over the past 100kya is below the neck!”

People who say this need to explain exactly what shields the brain from selection pressures. Man originated in Africa, the descendants of the soon-to-be coalesced races spent tens of thousands of years in differing environments. You need to do different things to survive in different environments. Just as the races differ physically, they differ mentally as well. Evolution did not stop at the neck. Significant changes in the brain have occurred in the past 10,000 years. There was a trade-off with agriculture, in that it was responsible for the population explosion which was responsible for mutations that affect intelligence and thus get selected for.

The “N” word is not a scary word. It is, in fact, it’s just common sense. People need to realize that by accepting genetic explanations for black domination in sports, that they would then, logically, have to accept racial differences in intelligence. It makes no sense to accept evolutionary theories (even if you don’t know it) in regards to athletics and not accept the same evolutionary theories for racial differences in the brain. There are real differences between populations, in both anatomy/physiology and our mental faculties and brain organization. If you accept one, you have to accept the other.

Racial Differences in Somatype

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One’s somatype is, really, the first thing they notice. Somatypes are broken down into three categories: ectomorph (skinny build), endomorph (rounder, fatter build) and mesomorph (taller, more muscular build). Like numerous other traits, different races and ethnies fall somewhere in between these three soma categories. Africans are meso, while Europeans are endo, while East Asians are more endo than Europeans. Differences in somatype, too, lead to the expected racial differences in sports due to differing anatomy and fat mass.

History of somatyping

The somatype classification was developed by psychiatrist William Sheldon in the 1940s, while releasing a book in 1954 titled Atlas of Men: Somatotyping the Adult Male At All AgesHe theorized that one’s somatype could predict their behavior, intelligence, and where they place socially. Using nude posture photos from his Ivy League students, he grouped people into three categories based on body measurements and ratios—mesomorph, endomorph, and ectomorph. Clearly, his theory is not backed by modern psychology, but I’m not really interested in that. I’m interested in the somatyping.

Somatypes

The three somatypes are endomorph, mesomorph, and ectomorph. Each type has different leverages and body fat distribution. Endomorphs are rounder, with short limbs, a large trunk, carry more fat in the abdomen and lower body, large chest, wide hips, and has hardly any muscular definition, yet gain strength easily. Ectomorphs, on the other hand, are taller, lankier with longer limbs, a narrow chest, thin body, short trunk and has little muscle.

There are further subdivisions within the three main types, mesomorphic-endomorph (meso-dominant), mesomorph-endomorph (both types are equal with less ectomorphy), ectomorphic-mesomorph, endomorphic-mesomorph, endomorph-ectomorph, and ectomorphic-endomorph. This can be denoted as “7-1-1”, which would indicate pure endomorph, “1-7-1” would indicate pure mesomorph and “1-1-7” would be a pure ectomorph. Further breakdowns can be made such as “1.6-2.7-6.4”, indicating the somatype is ecto-dominant. On the scale, 1 is extremely low while 7 is extremely high. The races, however, fall along racial lines as well.

Racial differences in somatype

West Africans and their descendants are the most mesomorphic. They also have the highest amount of type II muscle fibers which is a leading cause of their success in sporting events which call for short bursts of speed. Due to having longer limbs, they have a longer stride and can generate more speed. West Africans also have the narrowest hips out of all of the races (Rushton, 1997: 163) which further leads to their domination in sprinting competitions and events that take quick bursts of speed and power. However much success their morphology lends them in these types of competitions, their somatype hampers them when it comes to swimming. The first black American qualified for the Olympic swimming team in the year 2000. This is due to a narrower chest cavity and denser, heavier bones.

East Africans are most ectomorphic which you can see by their longer limbs and skinnier body. They have an average BMI of 21.6, one of the lowest in the world. Their low BMI, ectomorphic somatype and abundance of slow twitch muscle fibers are why they dominate in distance running events. Many explanations have been proposed to explain why East Africans (specifically Kenyans and Ethiopians) dominate distance running. The main factor is their somatype (ectomorphic) (Wilbur and Pitsiladis, 2012). The authors, however, downplay other, in my opinion, more important physiologic characteristics such as muscle fiber typing, and differences in physiology. Of course their somatype matters for why they dominate, but other important physiologic characteristics do matter. They clearly evolved together so you cannot separate them.

Europeans are more endo than East Africans and West Africans but less so than East Asians. Europeans have a strong upper body, broad shoulders, longer and thicker trunk and shorter extremities along with 41 percent slow twitch fibers compared to blacks’ 33 percent slow twitch fibers. This is why Europeans dominate power sports such as powerlifting and the World’s Strongest Man. Eighty to 100 percent of the differences in total variation in height, weight, and BMI between East Asians and Europeans are associated with genetic differences (Hur et al, 2008). If the variation between East Asians and Europeans on height, weight and BMI are largely attributed to genetic factors, then the same, I assume, should be true for Africans and Europeans/East Asians.

East Asians are the most endomorphic race and have lighter skeletons and more body fat. They have short arms and legs with a large trunk, which is a benefit when it comes to certain types of lifting movements (such as Olympic lifting, where East Asians shine) but hampers them when it comes to sprinting and distance running (although they have higher rates of type I fibers). East Asians also have more body fat at a lower BMI which is further evidence for the endomorphic somatype. This is also known as ‘TOFI’, ‘Thin on the Outside, Fat on the Inside’. Chinese and Thai children had a higher waist circumference and higher trunk fat deposits than Malay and Lebanese children (Liu et al, 2011). This is a classic description of the endomorphic individual.

Human hands and feet are also affected by climate. Climatic variation played a role in shaping the racial somatic differences we see today. The differences seen in hands and feet “might be due to the presence of evolutionary constraints on the foot to maintain efficient bipedal locomotion” (Betti et al, 2015).

Black-white differences in somatype

Fifty percent of the variability in lean mass is due to genetic factors (Arden and Specter, 1997) with the heritability of stature 85 percent in a meta-analysis (Peeters et al, 2009). Racial differences in somatype are also seen at a young age (Malina, 1969). Blacks had better muscular development and less fat-free mass at an early age. Vickery et al (1988) argued that since blacks have thinner skin folds that caliper measurements testing differences in body fat would be skewed. Malina (1969) also reports the same. Note that Malina’s paper was written in 1969, literally right before it got pushed on the American populace that fat was bad and carbohydrates were good.

Looking at the two tables cited by Malina (1969) on somatype we can see the difference between blacks and whites.

Data from Malina, (1969: 438) n Mesomorph Ectomorph Endomorph
Blacks 65 5.14 2.99 2.92
Whites 199 4.29 2.89 3.86
Data from Malina (1969: 438) Blacks Whites
Thin-build body type 8.93 5.90
Submedium fatty development 48.31 29.39
Medium fleshiness 33.69 43.63
Fat and very fat categories 9.09 21.06

Since this data was collected literally before we went down the wrong path and wrongly demonized fat and (wrongly) championed carbohydrates, this is an outstanding look at somatype/fat mass before the obesity epidemic. There is a clear trend, with blacks being more likely to have lower levels of fat-free body mass while also more likely to be mesomorphic. This has a ton of implications for racial differences in sports.

Somatype is predicated on lean mass, stature, bone density and fat-free body mass. Since racial differences appear in somatype at an early age, there is a great chance that the differences in somatype are genetic in nature.

College (American) football players are more likely to be endo-mesomorphs while high-school football players were more likely to be mesomorphs (Bale et al, 1994). This partly explains black over representation in football. Further, basketball, handball, and soccer players in Nigeria were taller, heavier, and had lower percent body fat than other athletic groups (Mazur, Toriola, and Igobokwe, 1985). Somatic differences have a lot to do with domination in sports competition.

Somatic differences are also seen in boxing. Elite boxers are more likely to have a mesomorphic somatype compared to non-athletes. Higher weight divisions were also more likely to be mesomorphic and endomorphic than the lower weight divisions which skewed ectomorphic (Noh et al, 2014). Blacks do well in boxing since they have a more mesomorphic somatype. Due to their higher levels of type II fibers, they can be quicker and throw more forceful punches which translates to boxing success.

Conclusion

Racial differences in somatype are another key to the puzzle to figure out why the races differ in elite sporting competition. The races evolved in different geographic locations which then led to differences in somatype. West African sports dominance is explained by their somatype, muscle fiber type, and physiology. The same can be said for Europeans in strength sports/powerlifting sports, and East Asians with ping-pong and some strength sports (though, due to lower muscle mass they are the least athletic of the races). I am not, of course, denying the impact of determination to succeed or training of any kind. What one must realize, however, is that one with the right genetic makeup/somatype and elite training will, way more often than not, outperform an individual with the wrong genetic makeup/somatype and elite training. These inherent differences between races explain the disparities in elite sporting competitions.

References

Arden, N. K., & Spector, T. D. (1997). Genetic Influences on Muscle Strength, Lean Body Mass, and Bone Mineral Density: A Twin Study. Journal of Bone and Mineral Research,12(12), 2076-2081. doi:10.1359/jbmr.1997.12.12.2076

Bale P, Colley E, Mayhew JL, et al. Anthropometric and somatotype variables related to strength in American football players. J Sports Med Phys Fitness 1994;34:383–9

Betti, L., Lycett, S. J., Cramon-Taubadel, N. V., & Pearson, O. M. (2015). Are human hands and feet affected by climate? A test of Allen’s rule. American Journal of Physical Anthropology,158(1), 132-140. doi:10.1002/ajpa.22774

Hur, Y., Kaprio, J., Iacono, W. G., Boomsma, D. I., Mcgue, M., Silventoinen, K., . . . Mitchell, K. (2008). Genetic influences on the difference in variability of height, weight and body mass index between Caucasian and East Asian adolescent twins. International Journal of Obesity,32(10), 1455-1467. doi:10.1038/ijo.2008.144

Liu, A., Byrne, N. M., Kagawa, M., Ma, G., Kijboonchoo, K., Nasreddine, L., . . . Hills, A. P. (2011). Ethnic differences in body fat distribution among Asian pre-pubertal children: A cross-sectional multicenter study. BMC Public Health,11(1). doi:10.1186/1471-2458-11-500

Malina, R. M. (1969). Growth and Physical Performance of American Negro and White Children: A Comparative Survey of Differences in Body Size, Proportions and Composition, Skeletal Maturation, and Various Motor Performances. Clinical Pediatrics,8(8), 476-483. doi:10.1177/000992286900800812

Mathur, D. N., Toriola, A. L., & Igbokwe, N. U. (1985). Somatotypes of Nigerian athletes of several sports. British Journal of Sports Medicine,19(4), 219-220. doi:10.1136/bjsm.19.4.219

Noh, J., Kim, J., Kim, M., Lee, J., Lee, L., Park, B., . . . Kim, J. (2014). Somatotype Analysis of Elite Boxing Athletes Compared with Nonathletes for Sports Physiotherapy. Journal of Physical Therapy Science,26(8), 1231-1235. doi:10.1589/jpts.26.1231

Peeters, M., Thomis, M., Beunen, G., & Malina, R. (2009). Genetics and Sports: An Overview of the Pre-Molecular Biology Era. Genetics and Sports Medicine and Sport Science, 28-42. doi:10.1159/000235695

Rushton J P (1997). Race, Evolution, and Behavior. A Life History Perspective (Transaction, New Brunswick, London).

Vickery SR, Cureton KJ, Collins MA. Prediction of body density from skinfolds in black and white young men. Hum Biol 1988;60:135–49.

Wilber, R. L., & Pitsiladis, Y. P. (2012). Kenyan and Ethiopian Distance Runners: What Makes Them so Good? International Journal of Sports Physiology and Performance,7(2), 92-102. doi:10.1123/ijspp.7.2.92

Possibly Retracting My Article on HBD and Baseball

700 words

I am currently reading Taboo: Why Black Athletes Dominate Sports and Why We’re Afraid To Talk About It and came across a small section in the beginning of the book talking about black-white differences in baseball. It appears I am horribly, horribly wrong and it looks like I may need to retract my article HBD and Sports: Baseball. However, I don’t take second-hand accounts as gospel, so I will be purchasing the book that Entine cites, The Bill James Baseball Abstract 1987 to look into it myself and I may even do my own analysis on modern-day players to see if this still holds. Nevertheless, at the moment disregard the article I wrote last year until I look into this myself.


Excerpt from Taboo: Why Black Athletes Dominate Sports and Why We’re Afraid To Talk About It:

Baseball historian Bill James, author of dozens of books on the statistical twists of his favorite sport believes this trend [black domination in baseball] is not a fluke. In an intriguing study conducted in 1987, he compared the careers of hundreds of rookies to figure out what qualities best predict who would develop into stars. He noted many intangible factors, such as whether a player stays fit or is just plain lucky. The best predictors of long-term career success included the age of the rookie, his defensive position as a determinant in future hitting success (e.g., catchers fare worse than outfielders), speed, and the quality of the player’s team. But all of these factors paled when compared to the color of the player’s skin.

“Nobody likes to write about race,” James noted apologetically. “I thought I would do a [statistical] run of black players against white players, fully expecting that it would show nothing in particular or nothing beyond the outside range of chance, and I would file it away and never mention that I had looked at the issue at all.

James first compared fifty-four white rookies against the same number of black first-year players who had comparable statistics. “The results were astonishing,” James wrote. The black players:

* went on to have better major-league careers in 44 out of 54 cases

* played 48 percent more games

* had 66 percent more major league hits

* hit 93 percent more triples

* hit 66 percent more home runs

* scored 69 percent more runs

* stole 400 more bases (Entine, 2000: 22-23)

Flabbergasted at what he found, James ran a second study using forty-nine black/white comparisons. Again, blacks proved more durable, retained their speed longer, and were consistently better hitters. For example, he compared Ernie Banks, a power hitting shortstop for the Chicago Cubs, and Bernie Allen who broke in with Minnesota. They both reached the majors when they were twenty-three years old, were the same height and weight, and were considered equally fast. Over time, Allen bombed and Banks landed in the Hall of Fame. (Entine, 2000: 24)

In an attempt to correct for possible bias, James compared players with comparable speed statistics such as the number of doubles, triples, and stolen bases. He ran a study focused on players who had little speed. He analyzed for “position bias” and made sure that players in the same eras were being compared. Yet every time he crunched the numbers, the results broke down across racial lines. When comparing home runs, runs scored, RBIs or stolen bases, black players held an advantage a startling 80 percent of the time. “And I could identify absolutely no bias to help explain why this should happen,” James said in disbelief.

James also compared white Hispanic rookies whom he assumed faced an uphill battle similar to that for blacks, with comparable groups of white and black players. The blacks dominated the white Latinos by even more than they did white North Americans, besting them in 19 of the 26 comparisons. Blacks played 62 percent more games, hit 192 more home runs, drove in 125 percent more runs, and stole 30 percent more bases.

So why have blacks become the stars of baseball far out of proportion to their relative numbers? James eventually concluded that there were two possible explanations: “Blacks are better athletes because they are born better athletes, which is to say that it is genetic, or that they are born equal and become better athletes. (Entine, 2000: 24-25)

Man the Athlete

5450 words

Homo nerdicus or Homo athleticus? Which name more aptly describes Man? Without many important adaptations incurred throughout our evolutionary history, modern Man as you see him wouldn’t be here today. The most important factor in this being our morphology and anatomy which evolved due to our endurance running, hunting, and scavenging. The topics I will cover today are 1) morphological differences between hominin species and chimpanzees; 2) how Man became athletic and bring up criticisms with the model; 3) the evolution of our aerobic physical ability and brain size; 4) an evolutionary basis for sports; and 5) the role of children’s playing in the evolution of human athleticism.

Morphological differences between Man and Chimp

Substantial evolution in the lineage of Man has occurred since we have split from the last common ancestor (LCA) with chimpanzees between 12.1 and 5.3 mya (Moorjani et al, 2016; Patterson et al, 2006). One of the most immediate differences that jump out at you when watching a human and chimpanzee is such stark differences in morphology, in particular, how we walk (pelvic differences) as well as our arm length relative to our torsos. Though we both evolved to be proficient at abilities that had us become evolutionarily successful in the environments we found ourselves in, one species of primate went on to become the apes the took over the world whereas the chimps continued life as the LCA did (as far as we can tell). The evolution of our athleticism is why we have a lean body with the right morphology for endurance running and associated movements. In fact, the evolution of our brain size hinged on a reduction in our fat depots (Navarette, Schaik, and Isler, 2011).

One of the largest differences you can see between the two species is how we walk. Chimps are “specially adapted for supporting weight on the dorsal aspects of middle phalanges of flexed hand digits II–V” (Tuttle, 1967). Meanwhile, humans are specifically adapted for bipedality due to the change in our pelvis over the course of our evolution (Gruss and Schmitt, 2015). Due to staying more arboreal than venturing on the ground, chimp morphology over the course of the divergence became more and more adapted to life in the trees.

Our modern gait is associated with physiologic and anatomic adaptations throughout our evolution, and are not ‘primitive retentions’ from the LCA (Schmitt, 2003). There are very crucial selective pressures that need to be looked at to see which selection pressures caused us to become athletes. Parts of Austripolithicenes still live on in us today, most notably in our lower leg/foot (Prang, 2015). Further, our ancestor, the famous Lucy had the beginnings of a modern pelvis, which was the beginning of the shift to the more energetically efficient bipedality, one thing that fully separates Man from the rest of the animal kingdom.

Of course, no conversation about human evolution would be complete without talking about Erectus. Analysis of 1.5 million-year-old footprints shows that Erectus was the first to have a humanlike weight transfer while walking, confirming “the presence of an energy-saving longitudinally arched foot in H. Erectus.” (Hatala et al, 2016). We have not yet discovered a full Homo erectus foot, but 1.5 million-year-old footprints found in Kenya show that whatever hominin made those prints had a long, striding gait with a full arch (Steudel-Numbers, 2006; Bennett et al, 2009). The same estimates from Steudel-Numbers (2006) show that Erectus nearly halved its travel costs compared to australopithecines. This is due to a longer stride which was much more Manlike than apelike due to a humanlike pelvis and gluteus maximus (Lieberman et al, 2006).

However, the most important adaptations that Erectus evolved was the ability to keep cool while walking long distances. Loss of hair loss specifically allowed individuals to be active in hot climates without overheating. Our ancestors’ hair loss facilitated sweating (Ruxton and Wilkinson, 2011b), which allowed us to become the proficient hunters—the athletes—that we would become. There is also thermoregulatory evidence that endurance running may have been possible for Homo erectus, but not any other earlier hominin (Ruxton and Wilkinson, 2011a) which was the beginnings of our selection to become athletes. The evidence reviewed in Ruxton and Wilkinson (2011a) shows that once hair loss and sweating ability reached human levels, thermoregulation was then possible under the midday sun.

Moreover, our modern gait and bipedalism is 75 percent less costly than quadrupedal/bipedal walking in chimpanzees (Sockel, Raichlen, and Pontzer, 2007), so this extra energy that was conserved with our physiologic and anatomic adaptations due to bipedalism could have gone towards other pertinent metabolic functions—like fueling a bigger brain (more energy could be used to feed more neurons).

Born to run

Before getting into how we are able to run so efficiently, I need to talk about what made it possible for us to be able to have the energy to sustain our distance running. That one thing is eating cooked food (meat). This one seemingly simple thing is the ‘prime mover’ so to speak, of our success as athletes. Eating cooked food significantly increases the amount of energy obtained during digestion. That we could extract more energy out of cooked food—no matter what type of food it was—can not be overstated. This is what gave us the energy to hunt and scavenge. We are, of course, able to hunt/scavenge while fasted, which is an extremely useful evolutionary adaptation which increases important hormones to have us search for food. The hormones released during a fasted state aid in human physiologic/metabolic functioning allowing one who is searching for food more heightened sensibilities.

We are evolutionarily adapted to be endurance runners. Endurance running is defined as the ability to run more than 5 km using aerobic metabolism (Lieberman and Bramble, 2007). Since we are poor sprinters, the idea is that our body has evolved for walking. However, numerous anatomical changes in our phenotypes in comparison to our chimp ancestors have left us some clues. In the previous section, I talked about physical changes that occurred after Man and Chimp diverged, well those evolutionary changes are why we evolved to be athletic.

Endurance running first evolved, most likely due to scavenging and hunting (Lieberman et al, 2009). Through natural selection—survival of the ‘good enough’, those who had better physiologic and anatomic adaptations could reach the animal carcass before other scavengers like vultures and hyenas could get to it. Over time, this substantially changed how we would look. Numerous physiologic changes in our lineage attest to the evolution of our endurance running. The nuchal ligament, as well as the radius of the semicircular canal is larger in Homo sapiens than in chimpanzees or australopithecines. This stabilizes our head while running—something that our ancestors could not do because they didn’t have a canal our size (Bramble and Lieberman, 2004).

Skeletal evidence that points to our evolution as athletes consists of (but not limited to):

  • The Nuchal ligament—stabilizes the head
  • Shoulder and head stabilization
  • Limb length and mass (we have legs longer than our torsos which decreases energy used)
  • Joint surface (we can absorb more shock when our feet hit the ground due to a larger surface area)
  • Plantar arch (generates spring for running but not walking)
  • Calcaneal tuber and Achilles tendon (shorter tuber length leads to a longer Achilles heel stretch, converting more kinetic energy into  elastic energy)

So people who had anatomy closer to this in our evolutionary past had more of a success of getting to that animal carcass, divvying it amongst his family/tribe, ensuring the passage of his genes to the next generation. Man had to be athletic in order to be able to run for long distances. Where this would have come in handy the most would have been the Savanna in our ancestral past. Man could now use persistence hunting—chasing animals in the heat of the day—and kill them when they tired out. The evolutionary adaptation sweating due to the loss of our fur is the only reason this is possible.

One of the most important adaptations for endurance running is thermoregulation. All humans are adapted for long range locomotion rather than speed and to dump rather than retain heat (Lieberman, 2015). This is one of the most important adaptations we evolved that had us become successful endurance runners. We could chase down prey and wait for our prey to become exhausted/overheat and then we would move in for the kill. Of course, intelligence and sociality come into play as we needed to create hunting bands, but without our superior endurance running capabilities—that no other animal in the animal kingdom has—we would have gone down a completely different evolutionary path than the one we went down. Our genome has evolved to support endurance running (Mattson, 2012). Since there is an association between too much sitting and all-cause mortality (Biddle et al, 2016), this is yet more evidence that we evolved to be mobile, not sedentary hominins.

Further evidence that we evolved to be athletic is in our hands. When you think about our hands and how we can manipulate our environments with them—what sets us apart from every other species—then, obviously, in our evolutionary past, those who were more successful would have had a higher chance of reproducing. Aggressive clubbing and throwing are thought to be one of the earliest hominin specializations.  If true, then those who could club and throw best would have the best chance of passing their genes to the next generation, thusly selecting for more efficient hands (Young, 2003). While we may have evolved more efficient hands over time warring with other hominins, some are more prone to disk herniation.

Plomp et al (2015) propose the ‘ancestral shape hypothesis’ which is derived from studying bipedalism. They propose that those who are more prone to disk herniation preferentially affects those who have vertebrae “towards the ancestral end of the range of shape variation within H. sapiens and therefore are less well adapted for bipedalism” (Plomp et al, 2015). One of the most amazing things they discovered was that humans with signs of intervertebral disc herniation are “indistinguishable from those of chimpanzees.” Of course, due to this, we should then look towards evolutionary biology in regards to a lot of human ailments (which I have also argued here on dietary evolutionary mismatches as well as on obesity).

Of course there are some naysayers arguing that endurance running didn’t drive our evolution. He wrongly states that it’s about what drove the evolution of our bipedalism; however, what the endurance running hypothesis argues is that there are certain physiologic and anatomic changes that only could have occurred from endurance running. Better endurance runners got selected for over time, leading to novel adaptations that stayed in the gene pool and got selected for. One thing is a larger gluteus maximus. A humanlike pelvis is found in the fossil record as far back as 1.9 mya in Erectus (Lieberman et al, 2006). Furthermore, longer toes had a larger mechanical cost, and were thusly selected against, which also helped in the evolution of our endurance running (Rolian et al, 2009). All in all, there are too many adaptations that our bodies have that can only be explained by adapting to endurance running. Just because we may have gotten to the weaker animals sometimes doesn’t falsify the hypothesis; Man still needed to sweat and persist in the hot mid-day temperatures chasing prey.

Brain size and aerobic physical capacity

When speaking about the increase in our brain size/neuronal count, fire/cooking, the social brain hypothesis, and other theories are brought up first. Erectus had a lot of humanlike qualities, including the ability to control/use fire (Berna et al, 2012), and the appearance of our modern gait/stride which first appeared in Erectus (Steudel-Numbers, 2006; Bennet et al, 2009). This huge change also occurred around the time our lineage began cooking meat/using fire. Without the increased energy from cooking, we wouldn’t be able to hunt for too long. However, we do have very important specific adaptations during a fasted state—the release of hormones such as catecholamines (adrenaline and noradrenaline) which have as react faster to predators/possible prey. Though, a plant-based diet wouldn’t cut it in regards to our daily energy requirements to feed our huge brain with a huge neuronal count (Fonseca-Azevedo and Herculano-Houzel, 2012). Cooked meat is the only way we’d be able to have enough energy required to hunt game.

What kind of an effect did it have on our cranial capacity/evolution?

Four groups of mice selectively bred for high amounts of “voluntary wheel-running”, ran 3 times further than the controls which increased Vo2 max in the mice. Those mice had higher levels of BDNF (Brain Derived Neurotrophic Factor) several days after the experiment concluded as well as also showing greater cell creation in the hippocampus when allowed to run compared to the controls. In two lines of selected mice, the hormone VEGF (Vascular Endothelial Growth Factor) which was correlated with higher muscle capillary density compared to controls. This shows that the evolution of endurance running in mice leads to important hormonal changes which then affected brain growth (Raichlen and Polk, 2012).

The amount of oxygen our brains use increased by 600 percent compared to 350 percent for our brain size over the course of our evolutionary history. This is important. What would cause an increase in oxygen consumption to the brain? Endurance running. There was further selection in our skeleton for endurance running in our morphology such as the semicircular canal radii. The first humanlike semicircular canal radii were found in Erectus (Spoor, Wood, and Zonneveid, 1994). This meant that we had the ability for running and other agile behaviors which were then selected for. There is also little to no activation of the gluteus medius while walking (Lee et al, 2014), implying that it evolved for more efficient endurance running.

Controlling for body mass in humans, extinct hominins and great apes, Raichlen and Polk (2012) found significant positive correlations with encephalization quotient and hindlimb length (0.93), anterior and posterior radii (0.77 and 0.66 respectively), which support the idea that human athletic ability is tied to neurobiological evolution. A man that was a better athlete compared to another would have a better chance to pass on his genes, as physical fitness is a good predictor of biological fitness. Putting this all together, selection improved our aerobic capacity over our evolutionary history by specifically altering signaling systems responsible for metabolism and oxygen intake (BDNF, VEGF, and IGF-1 (insulin-like growth factor 1), responsible for the regulation of growth hormone), which are important for blood flow, increased muscle capillary density, and a larger brain.

Putting this all together, selection improved our aerobic capacity over our evolutionary history by specifically altering signaling systems responsible for metabolism and oxygen intake (BDNF, VEGF, IGF-1). More evidence is needed to corroborate Raichlen and Polk’s (2012) hypothesis. However, with what we know about aerobic capacity and the hormones that drive it and brain size, we can make inferences based on the available data and say, with confidence, that part of our brain evolution was driven by our increased aerobic capacity/morphology, with the catalyst being endurance running. Though with our increased proclivity for athleticism and endurance running, when we became ‘us’, this just shifted the competition and athletic competition—which, hundreds of thousands/millions of years ago would mean life or death, mate or no mate, food or no food.

Clearly, without the evolution of our bipedalism/athleticism we wouldn’t have evolved the brains we have and thus we would be something completely different today.

Sport and evolutionary history

We crowd into arenas to watch people compete against each other in athletic competition. Why? What are the evolutionary reasons behind this? One view is that sport (and along with it playing) was a way for men to get practice hunting game, with playing also affecting children’s ability to assess the strength of others (Lombardo, 2012).

In an evolutionary context, sports developed as a way for men to further develop skills in order to better provide for his family, as well as assessing other men’s physical strength so he can adapt his fighting to how his opponent fights in a possible future situation. Men would then be selected for these advantageous traits. You see people crowd into arenas to watch their favorite sports teams. We are ‘wired’ to like these types of competitions, which then leads to more competition. Since we evolved to be athletes, then it would stand to reason that we would like to watch others be athletic (and hit each other as hard as they can), as a type of modern-day gladiator games.

Better hunters have better reproductive success (Smith, 2004). Further, hunter-gatherer men with lower-pitched voices have more children, while men with higher-pitched voices had higher child mortality rate (Apicella, Feinberg, and Marlowe, 2007). This signals that the H-G men with more children have higher testosterone than others, which then attracts more women to them. Champion athletes, hunters, and warriors all obtain high reproductive success. Women are sexually attracted to certain traits, which events of human athleticism show. However, men follow sports more closely than women (Lombardo, 2012), and for good reason.

Men may watch sports more than women since, in an evolutionary context, they may learn more about potential allies and who to steer clear from because they would get physically dominated. Further, men could watch the actions of others at play and mimic their actions in an attempt to gain higher status with women. Another reason is a man’s character: you can see a man’s character during sports competition and by watching one’s actions closely during, for instance, playing, you can better ascertain their motivations during life or death situations. Men may also derive thrills from watching “idealized men” perform athletic activities. These are consistent with Lombardo’s (2012) male lek hypothesis, “where male physical prowess and the behaviors important in conflict and cooperation are displayed by athletes and evaluated primarily by male, not female, spectators.”

Testosterone changes based on whether one’s favorite sports team wins or loses (Bernhardt et al, 1998). This is important. Testosterone does change under stressful/group situations. Testosterone is also argued to have a role in the search for, and maintenance of social status (Eisenegger, Haushofer, and Fehr, 2011). Testosterone responses to competition in men are also related to facial masculinity (Pound, Penton-Voak, and Surrin, 2009). Male’s physical strength is also signaled through facial characteristics of dominance and masculinity, considered attractive to women (Fink, Neave, and Seydel, 2007). Since testosterone fuels both competition, protectiveness and confidence (Eisenegger et al, 2016), a woman would be attracted to a man’s athleticism/strength, which would then be correlated with his facial structure further signaling biological fitness to possible mates. Testosterone doesn’t cause prostate cancer, as is commonly stated (Stattin et al, 2003; Michaud, Billups, and Partin, 2015). Testosterone is a beneficial hormone; you should be worried way more about low T than high T. Further, young men interacting with similar young men increases testosterone while interacting with dissimilar men decreases testosterone (DeSoto et al, 2009). This lends credence to the hypothesis that testosterone raises in response to male-male competition.

Since testosterone is correlated with the above traits, and since athletes have higher testosterone than non-athletes (Wood and Stanton, 2011) then certain types of males would be left in the dust. Athleticism can be looked at as a way to expend excess energy. Those with more excess energy would be more sexually attractive to women and mating opportunities would increase. This is why it’s ridiculous to believe that we evolved to be the ‘nerds’ of the animal kingdom when so much of our evolutionary success has hinged on our athleticism and superior endurance running and other athletic capabilities.

Playing

Child’s play is how children feel out the world in a ‘setting’ in which there are no real-world consequences so they can get a feel for how the world really is. Human babes are born helpless, yet with large heads. Natural selection has lead to large brains to care for children, causing earlier childbirths and making children more helpless, which selected for higher intelligence causing a feedback loop (Piantadosi and Kidd, 2016). They show that across the primate genera, the helplessness of an infant is an extremely strong predictor of adult intelligence.

Indeed, a lot of the crucial shaping of our intelligence and motor capabilities are developed in our infancy and early childhood, which we have over chimpanzees. Blaisdell (2015) defines play as: “an activity that is purposeless in that it tends to be detached from the outcome, is imperfect from the goal-directed form of the activity, and that tends to occur when the individual is in a non-stressed state.” Playing is just a carefree activity that children do to get a feel for the world around them. During this time, skills are honed that, in our ancestral past, allowed us to survive and prosper during times of need (persistence hunting, scavenging, etc).

Anthropological evidence also suggests that the existence of extended childhood in humans adapted to establish the skills and knowledge needed to be a proficient hunter-gatherer. Since there are no real-world outcomes to playing (other than increased/decreased pride), a child can get some physical experience without suffering the real life repercussions of failing. Studies of hunter-gatherers show that play fosters the skills needed to be proficient in tool-making and tool-use, food provisioning, shelter, and predator defense. Play time also hones athletic ability and the brain-body connection so one can be prepared for a stressful situation. In fact, children’s fascination with ‘why’ questions make them ‘little philosophers’, which is an evolutionary adaptation to prepare for possible future outcomes.

Think of play fighting. While play fighting, the outcome has no important real life applications (well, the loser’s pride is hit) and what is occurring is the honing of skills that are useful to survival. During our ancestral evolution, play fighting between brothers could have honed the skills needed during a life our death situation when another band of humans was encountered. As you begin to associate certain movements with certain events, you then become better prepared subconsciously for when novel situations occur. The advantage of an extended childhood with large amounts of play time allow the brain and body to make certain connections between things and when these situations arise during a life or death situation, the brain-body will already have the muscle memory to handle the situation.

Conclusion

Studying our evolution since the divergence between Man and chimp, we can see the types of adaptations that we have incurred over our evolutionary history that have lead to us being specifically adapted for long-term endurance running. The ability to sweat, which, as far as we know began with Erectus, was paramount in our history for thermoregulation. Looking at the evolution of our pelvis, toes, gluteal muscles, heads, shoulders, brains, etc all will point to how they are adapted to a bipedal ape that is born to run—born to be an athlete. Without our athleticism, our intelligence wouldn’t be possible. We have a brain-body connection, our brain isn’t the only thing that drives our body, the two work in concert giving each other information, reacting to familiar and novel stimuli. That’s for another time though.

We didn’t evolve to be Homo nerdicus, we evolved to be Homo athleticus. This can be seen with how exercise has such a huge impact on cognition. We can further see the relationship between our athletic ability and our cognition/brain size. Without the way our evolution happened, Man—along with everything else you see around you—would not be here today. In a survival situation—one in which society completely breaks down—one who has better control over his body and motor functions/capabilities will outlast those who do not. Ultimate and conscious control over our bodies, reacting to stimuli in the environment is fostered in our infancy during our play time with others. Playing allows an individual to get experience in a simulated event, getting important muscle memory to react to future situations. The brain itself, of course, is being molded during playing as well. This just attests to the large part that playing has on cognition, survival skills and athletic ability over our evolutionary history.

Aerobic capacity throughout our evolutionary history beginning with Erectus was paramount for what we have become today. Without the evolution of certain muscles like our gluteus maximus along with certain appendages that gave us the ability to trek/run long distances, we would have lost a very important variable in our brain evolution. Aerobic activity increases blood flow to the brain and so the more successful endurance runners/hunters would increase their biological fitness (as seen in Smith, 2004) and thusly those who were more athletically successful would have more children, increasing selection for important traits for endurance running/athleticism throughout our evolutionary history.

We still play sports today since we love competition. Testosterone fuels the need for competition and sports is the best way to engage in competition in the modern day. Women are much more attracted to men with higher levels of testosterone which in turn means a more masculinized face which signals dominance and testosterone levels during competition. Women are attracted to men with higher levels of testosterone and a more masculinized face. This just so happens to mirror athletes, who have both of these traits. However, being in top physical condition is not enough; an athlete must also have a strong mental background if, for instance, they wish to break world records (Lippi, Favaloro, and Guidi, 2008).

The evolution of human playing ties this together. These sports competitions that we have made hearken back to our evolutionary past and show who would have fared best in the past. When we play, we are feeling our competition and who we can possibly make allies with/watch out for due to their actions during playing. One would also see who he would likely need to avoid and form an alliance with as to not get on his bad side and prevent a loss of status in his band. This is what it really comes down to—loss of status. Higher-status men do have higher levels of testosterone, and by one losing to a more capable person, they show that they aren’t fit to lead and they fall in the social hierarchy.

To fully understand human evolution and how we became ‘us’ we need to understand the evolution of our morphology and how it pertains to things such as our cognition and overall brain size and what advantages/disadvantages it afforded us. Whatever the case may be, it’s clear that we have evolved to be athletic and any change in that makeup will lead to a decrease in quality of life.

Homo athleticus, not Homo nerdicus, best describes Man.

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