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Microbial Intelligence and Intelligent Physiology

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When organisms that we don’t normally signify as ‘intelligent’ do, indeed, show ‘intelligent’ behavior, our definition of the word—what we call ‘intelligent’ behavior—needs to be reevaluated. Bacteria and other microbes can certainly respond to cues from their environments and communicate with each other. So if bacteria can respond to environmental stimulus by having plastic behavior, then they do show a semblance of ‘intelligence’. Just because bacteria don’t talk doesn’t mean that they are not ‘intelligent’ in their own right.

Bacteria respond to cues from their environment, just like any other intelligent organism. That means that they have behavioral plasticity, the ability to change their behavior based on what occurs in their environments. Bacteria have been shown to exhibit behaviors we would call ‘intelligent’, i.e., acquiring information, storage, processing, use of information, perception, learning, memory, and decision-making (Lyon, 2015). It is proposed that “bacteria use their intracellular flexibility, involving signal transduction networks and genomic plasticity, to collectively maintain linguistic communication: self and shared interpretations of chemical cues, exchange of chemical messages (semantic) and dialogues (pragmatic)” (Jacob et al, 2004).

Clearly, bacteria can and do adapt at the phenotypic level, not only the genotypic level as some have asserted in the past. Using this definition of intelligence, that is, being able to perceive, process and integrate information about the state of the environment to change the organism’s behavior is intelligent behavior (Pinto and Mascher, 2016), all organisms, from bacteria to humans and in between are intelligent. If bacteria do show evidence of behavioral plasticity—and they do—then we must look at them as intelligent creatures, as well as come to the realization that all biological organisms are, in their own right, intelligent. Intelligence is not only for any ‘higher’ organisms; so-called ‘lower’ organisms do show behavioral plasticity, meaning they know what is occurring in their environment. Is that not intelligent?

Any organism that can immediately act in a different way when its environment changes can, in my opinion, be said to be intelligent. All biological organisms have this ability to ‘go off of their genetic coding’, if you will, and change their behavior to match what is currently going on in their environment. Furthermore, the number and fraction of single transduction genes can be used as a measure of ‘bacterial IQ’ (Sirota-Mahdi et al, 2010).

This, of course, has implications for our intelligent physiology. Since our physiological systems incorporate the intelligent processes of the intelligent cell, then, on a larger scale, our physiology is also intelligent. Our physiology is constantly responding to cues from the environment, attempting to maintain homeostasis. Since our body has a need to stay in homeostasis, then our physiological systems are indeed intelligent in their own right. They incorporate the processes of the intelligent cell; looking at our physiology in this way, we can see how and why these systems are intelligent.

Further, physiologists have been referring to physiological systems as “homeodynamic”, rather than “homeostatic”, seeing chaotic states as healthy “allowing organisms to respond to circumstances that vary rapidly and unpredictably, again balancing variation and optimization of order with impressive harmony” (Richardson, 2012). If our physiological systems can do this, are they not intelligent? Further, according to physiologist Dennis Noble, “Genes … are purely passive. DNA on its own does absolutely nothing until activated by the rest of the system through transcription factors, markers of one kind or another, interactions with the proteins. So on its own, DNA is not a cause in an active sense. I think it is better described as a passive data base which is used by the organism to enable it to make the proteins that it requires.”  So, as you can see, genes are nothing without the intelligent physiology guiding then. This is only possible with physiological systems, and this begins with the intelligent cell—intelligent microbes.

Some people misunderstand what genes are for and what they do in the body. The gene has long been misunderstood. People don’t understand that genes direct the production of proteins. Since physiological systems—at their core—are run by microbes, then the overall physiological system is itself intelligent. Genes, on their own, are not the masters but the servants. Genes do code for proteins that code for traits, but not under their own direction; they are directed by intelligent systems.

Think of how our gut microbiome co-evolved with us. Knowing what we now know about intelligent cells, we can also say that, by proxy, our microbiome is intelligent as well.

Understanding intelligent cells will lead us to understand intelligent physiology then, in turn, lead us to understand how genes are the servants—not the masters as is commonly asserted—of our traits. Physiology is an intelligent system, and since it is intelligent it can then react to cues from the environment, since it is made up of smaller cells, which make up the larger whole of the intelligent physiological system. These intelligent systems that we have evolved are due to the changeability of our environments in our ancestral past. Our physiology then evolved to be homeodynamic, attempting to maintain certain processes. The ever-changing environment that our genus evolved in is the cause for our homeodynamic intelligent physiology, which begins at the smallest levels of the cell.

The intelligent microbes are the smaller part of the larger whole of the intelligent physiological system. Due to this, we can say that at the smallest levels, we are driven by infinitesimally small microbes, which, in a way, guide our behavior. This can definitely be said for our gut microbiome which evolved with us throughout our evolutionary history. Our microbiome, for instance, had to be intelligent and communicate with each other to maintain our normal functioning. Without these intelligent cells, intelligent physiology would not be possible. Without ever-changing dynamic environments, our intelligent physiology and intelligent cells would have never evolved.

Intelligent physiology evolved due to the constant changeability of the new environments that our ancestors found themselves in. If we would have evolved in, say, more stable, unchanging environments, our physiological systems would have never evolved how they did. These intelligent physiological systems can buffer large ranges of physiological deficiencies. The evolvability of these systems due to the changeability of our ancestral environments is the cause of our amazing physiological intelligence, developmental plasticity, and microbial intelligence.

When you think about conception, when a baby is forming in the womb, it becomes easier to see how our physiological systems are intelligent, and how genes are the slaves—not masters—of our development. Intelligence is already in those little cells, it just needs an intelligent physiology for things to be set into motion. This all goes back to the intelligent cells which make up the larger part of intelligent physiology.

Marching Up the ‘Evolutionary Tree’?

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There are numerous misconceptions about evolution. One of the largest, in my opinion, is that there is some sort of intrinsic ‘progress’ to evolution. This is inferred from the fact that the first life—bacteria—are simpler and less ‘complex’ than so-called ‘higher’ organisms. This notion is still pushed by some, despite the fact that it is a discredited concept.

The concept of scala naturae was first proposed by Aristotle (Hodos, 2009; Werth, 2012; Diogo, Ziermann, and Linde-Medina, 2014). This notion was held until Darwin’s landmark book On the Origin of Species (Darwin, 1859) when Darwin proposed the theory of evolution by natural selection. However, the notion of the scala naturae is still entrenched in modern-day thought, from the layman all the way to educated scientists. This notion is wrong.

Neuroscientist Herculano-Houzel writes on page 94 of her book The Human Advantage A New Understanding of How Our Brain Became Remarkable:

Moreover, evolution is not synonmous with progress, but simply change over time. And humans aren’t even the youngest, most recently evolved species. For example, more than 500 new species of cichlid fish in Lake Victoria, the youngest of the great African Lakes, have appeared since it filled with water some 14,500 years ago.

When people think of ‘progression up this evolutionary tree’ they look at Man as the ultimate culmination of the evolutionary process—as if every event that occurred before the Dawn of Man was setting the stage for us to be here. This, of course, goes back to the scala naturae concept. The ‘lower’ animals are the ones that are less ‘complex’ than the ‘higher’ animals. The notion that there was a ‘march of progress’ towards Man is erroneous (see Gould, 1989: 27-45 for a review).

Indeed, even Darwin himself didn’t believe in some ‘straight line’ to the evolutionary process. In one of his notebooks, he drew a ‘coral of life’ (seen below):


Notice how there are no ‘lower’ or ‘higher’ organisms and each branch branches off to the side, with no way of denoting which organism has ‘progressed’ more?

The scala naturae proposes that inanimate objects, to plants, to animals can all be placed somewhere on this ladder of ‘progress’, which eventually culminate with Man at the top—as if we are the ultimate culmination of evolutionary history and time—like we were preordained to be here. The scala naturae is still with us today. Why should we view humans as ‘higher than’ other organisms? It doesn’t make sense. It’s clearly steeped in a large anthropometric bias.

Indeed, the scala naturae is so entrenched in our minds that modern-day biologists still use terms that would denote ‘higher’ and ‘lower’, the scala naturae. Rigato and Minelli (2013) data mined 67,413 biological articles published between the years 2005 and 2010 looking for signs of pre-evolutionary language (e.g., lower vs. higher vertebrates and lower vs. higher plants). Of the 67,413 article that were mined for data, 1,287 (1.91%) returned positive hits for scala naturae language. Shockingly, the journal Molecular Biology and Evolution had frequent scala naturae language (6.14 %) along with the journal Bioessays (5.6%) and the Annual Review of Ecology, Evolution, and Systematics (4.82%). Clearly, misconceptions about the nature of evolution can still persist in the modern-day amongst experts (that doesn’t mean that the notion of the scala naturae is correct since specialists still use some of the terminology, however). In terms of scala naturae thinking by country, Russia topped the list followed by Japan, Germany, Israel, and France.

This notion of ‘progress’ to evolution—that there is some sort of scala naturae with has ‘primitive’ organisms on the bottom with ‘advanced’ organisms at the top is wrong. When comparing organisms, the comparison isn’t between which organism is more ‘primitive’ or ‘advanced’. The comparison is between ancestral and derived, so the only meaningful comparison is to say that organism A is more like the common ancestor (ancestral) while organism B has derived traits in comparison to the common ancestor (Gregory, 2008).

It is further assumed that earlier organisms are more ‘primitive’ than organisms that are younger. This is false. Once organisms diverge from a common ancestor, they both share a mixture of ancestral and derived traits; ancestral and derived organisms share a mix of ancestral and derived traits from said common ancestor (Crisp and Cook, 2005: 122). Furthermore, ‘early’ does not denote ‘primitiveness’ (Gould, 1997: 36). So to say that, for instance, ‘this organism on this tree did less/no branching than others and is therefore primitive’ is incorrect. It is fallacious to make a comparison between ‘primitive’ and ‘advanced’ organisms. For instance, one may look at a phylogeny and see a straight line and assume that no change has occurred. This is wrong.

The terminology ‘driven’ and ‘passive’ is used to denote trends in complexity. Is the trend driven or passive? Large amounts of research has been done into this matter (Gould, 1996; McShea, 1996) with no clear-cut answer. What is increasing? Complexity? The thing about ‘complexity’ (whatever that is) is that it may be a trend, but it is not an inevitability (Werth, 2012: 2135). Since life began at the left wall—where no organism can get any simpler—there was only one way to go: up. Any organism that arises in between the left and right walls can either become more or less complex depending on what is needed in that particular ecosystem.

Gould (1996) speaks of a drunkard leaving a bar. The drunkard leans on the bar wall (the left wall of complexity) and continuously stumbles toward the gutter (the right wall of complexity). The drunkard may go back and forth, touching the bar wall all the while getting closer to the gutter which each stumble. The drunkard will—eventually—end up in the gutter. Now we can look at the right wall of complexity as us humans and the left wall as bacteria. Any organism caught in the middle of the walls can either get less or more complex, but no simpler than the left wall—where life began. Some may say that this denotes ‘progress’, however, since life began constrained at the left wall, there was no way to go but ‘up’.

McShea (1994: 1761) notes:

If such a trend in primates exists and it is driven, that is, if the trend is a direct result of concerted forces acting on most lineages across the intelligence spectrum, then the inference is justified. But if it is passive, that is, forces act only on lineages at the low-intelligence end, then most lineages will have no increasing tendency. In that case, most primate species—especially those out on the right tail of the distribution like ours—would be just as likely to lose intelligence as to gain it in subsequent evolution (if they change at all).

Are there any instances like this in our genus? Of course there are, with the most famous (and most studied) being Homo floresiensis. I’ve written twice before about how the evolution of floresiensis proves that 1) evolution is not progress and 2) large brains need high-quality energy and without that brain size—and body size—will shrink. Indeed, a new paper on the evolution of floresiensis lends credence to the idea that floresiensis is a derived form of erectus (Diniz-Filho and Raia, 2017). Their analysis lends credence to the support that floresiensis is derived from erectus and not habilis. No matter which hominin floresiensis evolved from, this shows how critical the quality of energy is for maintaining a large brain and body size and, without large amounts of high-quality energy then reductions in brain and body size will persist. This, yet again, lends more credence to my argument of non-progressive evolution.

Now, I must talk about the scala naturae and its involvement in attempting to figure out the evolution of the human brain. Does the supposed increase in brain size denote ‘progress’ in evolution? No, it does not.

Brains are made from metabolically expensive tissue; that is, the larger a brain is the more kcal are needed to power it. Brains and the tissue that compose it (along with other bodily structures) are so expensive that there is a trade-off between elaborate defense mechanisms and brain size—as EQ decreases, defense mechanisms get more elaborate and vice-versa (Stankowich and Romero, 2017).  So organisms don’t need intelligence—and [sometimes] the larger brain that comes with it—if they have evolved elaborate defense mechanisms to where they don’t need a large brain to survive.

The increase in brain size over the past few million years in our genus Homo is pointed at as proof that evolution is ‘progressive’, however that is literally only one metric and any wild swings in environment can and will select for smaller brains. The point is that increases in brain size are due to local change, so therefore trends in the opposite direction can and do occur. 

The terms ‘higher and lower’ in regards to the scala naturae have been discredited (Diogo, Ziermann, and Linde-Medina, 2014: 18). Indeed, when we believe that things may go our way when, say, we are testing ourselves compared to other animals we will invoke the scala naturae. But what if we humans are not the ‘best’ at any given task tested? Eleven animal species (including human infants) were tested to analyze color processing speed. First came honeybees, then fish, then birds and lastly human infants. Of course this contradicted the scala naturae concept, and some people even argued that learning speed is not a useful measure of intelligence (Chittka et al, 2012)! This scala naturae thinking would have us believe that we should be on top of the learning speed ‘pyramid’, yet when it’s found that we are not then we say that learning speed is not a useful measure of intelligence? Can you see the huge bias there?


Above is a figure from Mashour and Alkire (2013) which shows the evolution of the brain through the lens of the scala naturae concept on the left and the modern theory on the right. Clearly, with the modern theory, there is no such ‘progress’ or ‘inherent advancement’ from fish culminating to the brain of Man.

Modern theories of the scala naturae include John Bonner’s assertion that animals found in lower strat are ‘lower’ whereas those found in the higher strata are ‘higher’. This erroneous assumption made by Bonner, however, is corrected in subsequent publications (see Randomness in Evolution, Bonner, 2013). He stresses, as can be seen by the title of the book, that evolution is random and possibly non-drive (i.e., passive, see McShea, 1994, Gould, 1996) (Diogo, Ziermann, and Linde-Medina, 2014: 3). Furthermore, there is “no general trend to increase the number of muscles at the nodes leading to hominoids and to modern humans. That is, with respect to the muscles in the regions we have investigated, although modern humans accumulated more evolutionary transitions than the other primates included in our cladistic study, these evolutionary transitions did not result in more muscles, or more muscle components (Diogo & Wood, 2011, 2012a,b; Diogo et al., 2013b)” (Diogo, Ziermann, and Linde-Medina, 2014: 18). So looking at this one facet of hominin evolution (muscles), there is no general increase in the number of muscles at the nodes leading to our genus.

Next, one Dale Russel (who I have written about at length) needs to be addressed again. Russel asserts that had the dinosaurs not gone extinct, that one species of dinosaur, the troodon, would have evolved human-like bipedalism, a large brain among other traits. This is horribly incorrect. In his book (Russel, 1989) he denotes ever-increasing complexity, which, as I have noted, is due to the beginnings of life at the left wall of complexity. The behaviors of most dinosaurs which were inferred from skeletal morphology and trackways “may not have lain much outside the observed range in ectothermic crocodilians” (Hopson, 1977: 444), along with most dinosaur endocasts showing not showing a tendency for increased brain size (Hopson, 1977: 443). Further, since dinosaurs were tied to the sun their behavior was restricted, they needed to avoid getting too hot or cold and couldn’t explore and understand the world, and in turn wouldn’t have been able to evolve large brains—nevermind human-like intelligence (Skoyles and Sagan, 2002: 12). Russell’s contentions are moot.

On that same note, E.O. Wilson, author of the 1975 book Sociobiology asserts that evolution must be progressive (I will cover Wilson’s views on evolutionary progress in depth in the future) since life started prokaryotes with no nucleus, to eukaryotes with nucleus and mitochondria, then multi-cellular organisms with complex organs like eyes and brains and finally the emergence of the human mind (Rushton, 1997: 293). This, too, can be explained by life beginning at the left wall and having nowhere to go ‘but up’.

This finally brings me to JP Rushton who attempted to revive the scala naturae concept by (wrongfully) applying r/K selection theory to human races. Rushton argues that since Mongoloids are the ‘newest’ race that they are then the most ‘progressed’ and thusly are a pinnacle of evolution of Man. However, as anyone who understands evolution knows, evolution through natural selection is local change, not progress.

This notion of evolutionary progress, the scala naturae, and the ‘march up the evolutionary tree’ are all large misconceptions about the nature of evolution. This misconception arises due to only looking at the right tail of the variation. Of course, if you only looked at the right tail, you would assume that evolution is ‘progressive’, that there was a ‘march’ from simple to complex organisms. Why focus only on the complex end of the distribution of life? Because looking at the whole of life, bacteria is the mode (Gould, 1996; 1997). We are currently living in the age of the bacteria. That is the mode of all life, and that is why there is no ‘progress’ to evolution, nor any ‘march up an evolutionary tree’, because evolution through natural selection is local change, not progress.

Saying that evolution is progress doesn’t allow us to appreciate the full house of variation (Gould, 1996). Bacteria rule the earth, and will do so until the Sun explodes. What does that tell you about any ‘progress’ to life? Aboslutely nothing because bacteria have remained the most numerous lifeforms on the planet since life began.

Our View of ‘Intelligence’ Needs to Change

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What is intelligence? How would we define it? Would intelligence be reacting to what occurs in the immediate environment; having the ability to have behavioral plasticity or even communicating with others? Amazingly, bacteria have been found to do both things noted above: They have been found to be able to react to their environment, i.e., have the ability for plastic behavior and they have even been shown to communicate with one another. Hell, even something as simple as a slime mold has been found to navigate a maze to find food. Is that not intelligence?

Ken Richardson, author of the book Genes, Brains, and Human Potential: The Science and Ideology Behind Intelligence writes:

Living things, then, need to be good at registering those statistical patterns across everyday experience and then use them to shape the best response, including (in the cell) what genes to recruit for desired products. This is what intelligence is, and it’s origins coincide with the origins of life itself, and life is intelligence. (Richardson, 2017: 115)

In multicelluar systems, of course, the cells are not just responding to one another, but also collectively to the changing environment outside. That requires an intelligent physiology, as described in chapter 5. However, it is still the statistical structure of the changes that matters and that forms the basis of a living intelligence. Even at this level, closest to the genes, then, the environment is emphatically not a loose collection of independent factors to which the cells respond, in stimulus-response fashion, under gene control. This reality makes the additive statistical models of the behavioral geneticist quite unrealistic. (Richardson, 2017: 120)

Currently, our view of intelligence has an anthropometric lean. But, as I’ve been saying for months now, why should we view humans as a sort of ‘apex’ to evolution? Why should we be the measuring stick? If you really think about it to put us—our brains—at the top of a rank order as ‘the best’ and not recognize what other, smaller supposedly ‘archaic’ forms of life can do, then maybe it’s best to take off our human-centric glasses and look at the whole of the animal kingdom as intelligent—including bacteria, as they show the basic things necessary for what we would call  intelligence, i.e., behavioral plasticity.

In this paper published just two months ago, the authors write:

Bacteria are far more intelligent than we can think of. They adopt different survival strategies to make their life comfortable. Researches on bacterial communication to date suggest that bacteria can communicate with each other using chemical signaling molecules as well as using ion channel mediated electrical signaling. (Majumdar and Pal, 2017)

Furthermore, looking at definitions of the term ‘behavior’ from ethology, we can see that bacteria exhibit these behaviors that we have deemed ‘human’ or ‘human-like’:

  • “Externally visible activity of an animal, in which a coordinated pattern of sensory, motor and associated neural activity responds to changing external or internal conditions” (Beck et al. 1981)
  • “A response to external and internal stimuli, following integration of sensory, neural, endocrine, and effector components. Behavior has a genetic basis, hence is subject to natural selection, and it commonly can be modified through experience” (Starr and Taggart 1992)
  • “Observable activity of an organism; anything an organism does that involves action and/or response to stimulation” (Wallace et al. 1991)
  •  “What an animal does” (Raven and Johnson 1989)

Bacteria have been found to fit all of the criteria mentioned above. If organisms can react to how the environment changes, then that organism has—at least a semblance—of intelligence. Bacteria have also been found to be able to learn and they also have memories, so if this is true (and it is), then bacteria are intelligent. 

Finally, Westerhoff et al (2014) write that leaving out the terms ‘human’ and our brains as measuring sticks for what is intelligent, that “all forms of life – from microbes to humans – exhibit some or all characteristics consistent with “intelligence.” For people with anthropocentric views of evolution, however, this is a hard pill to swallow. If the data says that bacteria have evidence of ‘cognition’ and an ability to react to outside environmental cues then bacteria have a semblance of intelligence. There is no denying it.

We clearly need to look at intelligence in a different way—one that’s free of any anthropocentric bias—-and if we do, we would recognize numerous species as intelligent that we would never have thought of before since we view ourselves as some sort of ‘apex’ of evolution, that we are supreme on this earth, when the bacteria—the modal bacter—reign supreme and will continue to remain supreme until the Sun explodes. So if bacteria show the ability to communicate with one another and the ability to change their behavior when their environment changes, i.e., that they learn and have ‘memories’ of past events, then maybe it’s time for us to change from our human-centric view of intelligence (which makes a ton of sense; viewing us as an ‘apex’ of evolution makes no sense and doesn’t allow us to appreciate the wide range of variation on earth).

As Gould wrote in Full Houselooking at only the right tail we would believe that some sort of ‘progress’ reigns supreme, but looking at the whole sum of variation, we can see that the bacteria are the mode of all life, have been the mode of all life and will remain the mode of all life until the Sun explodes and all life forever perishes from Earth.

Dinosaurs, Brains, and ‘Progressive’ Evolution: Part II

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In part I, I showed how Dale Russel’s contention that the troodon would have evolved into a bipedal ‘dinosauroid’ with human locomotion and a human-sized brain was pure fantasy. I ordered the book of his that Rushton cited in his book Race, Evolution, and Behavior and I finally received it last week. When I read the relevant parts, I yawned because it’s the same old stuff that I’ve covered here on this blog numerous times. Since literally the only relevant part in the book about the troodon is the final 7 pages, that’s what I will cover today—along with a few more lines of evidence that large brains lie outside reptilian design (Gould, 1989).

First off, all of Rushton’s contentions in the final pages of his book (Rushton, 1997) need to be rebutted. Rushton (1997: 294) writes that dinosaur brains were ‘progressing’ in size for 140 million years, but neither of Russel’s writings that I have (Russel 1983; 1989) have the statement in them.

In the book Up From Dragons: The Evolution of Human Intelligence neuroscientist, evolutionary psychologist John Skoyles and science writer Dorian Sagan—the son of Carl Sagan—speak briefly about reptilian intelligence and why they wouldn’t have reached our levels of intellect:

But cold-bloodedness is a dead-end for the great story of this book—the evolution of intelligence. Certainly reptiles could evolve huge sizes, as they did over vast sweeps of Earth as dinosaurs. But they never could have evolved our quick-witted and smart brains. Being tied to the sun restricts their behavior: Instead of being free and active, searching and understanding the world, they spend too much time avoiding getting too hot or too cold. (Skoyles and Sagan, 2002: 12)

Hopson (1977: 443) writes:

I would argue, as does Feduccia (44), that the mammalian/avian levels of activity claimed by Bakker for dinosaurs should be correlated with a great increase in motor and sensory control and this should be reflected in increased brain size. Such an increase is not indicated by most dinosaur endocasts.

Most importantly, if some dinosaurs DID have bird-sized brains, the above contention would still hold. Hopson concludes that, except for coelurosaurs “the range of behaviors that existed in dinosaurs, as inferred from trackways and skeletal morphology, may not have lain much outside the observed range in ectothermic crocodilians” (Hopson, 1977: 444).

Since the conjecture/’thought experiment’ of the troodon was rebutted last week, it’s pretty conclusive that large brains lie outside of reptilian design; they need to spend so much time avoiding getting too hot or cold—as well as hunt and eat—so exploring the world and learning was not possible for them—along with the fact that they didn’t have a primate morphology and thus didn’t have the ability to fully manipulate their environment as we do which would further select for larger brains. However, as Hopson (1977) notes, animals with higher metabolic rates had larger brains; coelurosaurs had high metabolic rates and the largest dinosaur brains (Russel, 1983; 1989)—but that doesn’t mean they would have eventually evolved human-like intelligence, bipedalism or brain size and to say otherwise is fantasy.

Furthermore, there is large variation in encephalization and encephalization is not universal in mammals (Shultz and Dunbar, 2010).

Here is the thing about brain size increases: it is a local level trend. A local level trend is a trend that occurs within one or a few related species. This is exactly what characterized brain evolution; there is large variation depending on what the environment calls for (Boddy et al, 2012; Montgomery et al, 2012; see also island gigantism; Bromham and Cardillo, 2007; Welch, 2009; and also see the deep sea rule; Mcclain, Boyer, and Rosenberg, 2006). So these local trends differ by species—even one population split by, say, 50 miles of water will speciate and become evolve a completely different phenotype due to the environment of time. That is evolution by natural selection; local change, not any inherent or intrinsic ‘progress’ (Gould, 1996).

The same local level trend occurs with parasites. Now think about parasites. The get selected for ‘complexity’ or a decrease in ‘complexity’ depending on what occurs in their host. Now, looking at it from this perspective, the body is the host’s environment while the earth is ours; so my example for an environmental change would be, as usual, the asteroid impact hitting the earth blocking out the sun and decreasing high-quality food all throughout the earth. Surely I don’t need to tell you what would occur…

Russel (1989) writes:

Examples of evolutionary changes that occured at ever-increasing speeds include the initial diversification of animals in the sea 650 and 550 million years ago, the attainment of tree stature in land plants between 410 and 360 million years ago, and the diversification of mammals between 200 million years ago and the present. Changes like this have resulted in increased organismal complexity, which, in combination with a general increase in number of species, has made the biosphere of the modern Earth so much richer than it was several hundred million years ago. It is reasonable to suppose that animals living in a complex environment might find it advantageous to possess complex nervous systems in order to have access to a greater variety of responses. Indeed, the largest proportion of brain weight in an animal has also increased at an ever-increasing rate across geological time. The brain has become evidently larger in animals as diverse as insects, mollusks, and backboned creatures. Relative brain size can be taken as an indication of biotic interactions.

He references time periods that correspond with decimations (mass extinctions). Decimations lead to diversification. Think back to the Cambrian Explosion. During the Cambrian Explosion, many more lifeforms existed than can be currently classified. Therefore, according to the decimation and diversification model, greater diversity of life existed in the past. When decimations (defined as a reduction in the anatomical forms of life from mass extinction) occur, the niches that become extinct quickly become filled.

The time periods that Russel references are when mass extinctions occurred. This is how diversification occurs. What allowed for this ‘organismal complexity’ and increase in the number of species (though body plans are limited due to the Burgess Decimation) is due to the decimations. Decimation and diversification proves that evolution is not progressive.

A ‘trend’ in biology is directional change in a group stat using the mean, median or mode. Any existence of a trend from the mean (‘progress’) tells us nothing about the underlying mechanisms behind it.

To wrap this all up, even if a trend in X were to be discovered, it still wouldn’t tell us a thing about the underlying mechanisms causing it, nor will it tell us about any increasing tendency. 

The analogy of the drunkard’s walk (Gould, 1996) is why ‘progress’ doesn’t make sense. Further, niche construction matters as well. When organisms construct their own niches, change occurs based on those niche constructions. Milk-drinking 8kya in Europe and African farmers diverting water for their crops having mosquitoes come by and gaining a resistance to malaria are two examples of niche construction (Laland et al, 2009). That’s another barrier to progress!

In sum, Dale Russel says nothing I’ve not heard before in regards to ‘progressive’ evolution. He only describes ever-increasing ‘complexity’ which is due to decimations and further diversification by organisms to fill empty niches. Any type of ‘progress’ would have been stymied by mass extinctions.

Further, the fact that species can consciously—in a way—guide their own evolution through the manipulation of the environment once again shows how evolution doesn’t mean progress—it literally only means local change and any type of local change, no matter to what type of environment, will cause concurrent increases/decreases on whichever relevant traits that will give the organism the best chance for survival in that environment.

This is why evolution is not progressive; and even if scientists were to identify one thing, still, a causal mechanism won’t be able to be inferred. Ruseel (1989) describes right and left walls of complexity—nothing more. Dinosaurs didn’t have the body plans to have our brain size, bipedalism and intelligence, nor did they have the right type of blood, nor did they have the time to search and learn about the world due to being constrained to their cold-blooded system—being a slave to the sun, always attempting to avoid overheating or getting too cold (Skoyles and Sagan, 2002). The so-called ‘dinosauroid’ is an impossibility and implies a teleological lean to evolution—as if our morphology (or something similar from an unrelated organism) will always evolve if we replay the tape of life again (Gould, 1989; 1996). This is what Russel is pretty much arguing, and he is 100 percent wrong as noted above.


Bromham, L., & Cardillo, M. (2007). Primates follow the ‘island rule’: implications for interpreting Homo floresiensis. Biology Letters,3(4), 398-400. doi:10.1098/rsbl.2007.0113

Boddy, A. M., Mcgowen, M. R., Sherwood, C. C., Grossman, L. I., Goodman, M., & Wildman, D. E. (2012). Comparative analysis of encephalization in mammals reveals relaxed constraints on anthropoid primate and cetacean brain scaling. Journal of Evolutionary Biology,25(5), 981-994. doi:10.1111/j.1420-9101.2012.02491.x

Gould, S. J. (1989). Wonderful life: the Burgess Shale and the nature of history. New York: Norton.

Gould, S. J. (1996). Full House: The Spread of Excellence from Plato to Darwin. New York: Harmony Books.

Hopson, J. A. (1977). Relative Brain Size and Behavior in Archosaurian Reptiles. Annual Review of Ecology and Systematics,8(1), 429-448. doi:10.1146/

Laland, K. N., Odling-Smee, J., Feldman, M. W., & Kendal, J. (2009). Conceptual Barriers to Progress Within Evolutionary Biology. Foundations of Science, 14(3), 195–216.

Mcclain, C. R., Boyer, A. G., & Rosenberg, G. (2006). The island rule and the evolution of body size in the deep sea. Journal of Biogeography,33(9), 1578-1584. doi:10.1111/j.1365-2699.2006.01545.x

Montgomery, S. H., Capellini, I., Barton, R. A., & Mundy, N. I. (2010). Reconstructing the ups and downs of primate brain evolution: implications for adaptive hypotheses and Homo floresiensis. BMC Biology,8(1), 9. doi:10.1186/1741-7007-8-9

Russell, D. A. (1983). Exponential evolution: Implications for intelligent extraterrestrial life. Advances in Space Research,3(9), 95-103. doi:10.1016/0273-1177(83)90045-5

Russell, D. A. (1989). An Odyssey in Time: The Dinosaurs of North America. Minocqua, WI: Published by NorthWord Press in association with National Museum of Natural Sciences.

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

Shultz, S., & Dunbar, R. (2010). Encephalization is not a universal macroevolutionary phenomenon in mammals but is associated with sociality. Proceedings of the National Academy of Sciences,107(50), 21582-21586. doi:10.1073/pnas.1005246107

Skoyles, J. R., & Sagan, D. (2002). Up From Dragons: The Evolution of Human Intelligence. New York: McGraw-Hill.

Welch, J. J. (2009). Testing the island rule: primates as a case study. Proceedings of the Royal Society B: Biological Sciences,276(1657), 675-682. doi:10.1098/rspb.2008.1180

Modern Man Did Not Begin in Europe

1300 words

A lot of buzz is going around about a recent study that purports that the human-chimp split occurred in the Mediterranean—not Africa as is commonly thought (Fuss et al, 2017). This claim, however, is based off of a few teeth and jawbone with one tooth in it of a supposed hominin named Graecopithecus freybergi. A lot of wild conclusions are being jumped to about this study and these claims need to be put to rest.

On, an article was written titled Recent Discovery Shows Humans Came From Europe. The article claims that the OoA hypothesis has been “debunked by hard evidence”. Though to disprove the OoA hypothesis, a lot more will be needed than a few teeth and a jawbone. This is similar to another article on the Dailystormer, New Discovery Shows Pre-Human Hominids in Europe Before Africa, which, again, makes more wild claims.

white people are just Negroes who have lighter skin because during the Ice Age, they were wearing more clothing and thus needed lighter skin to absorb more Vitamin D. needed lighter skin to absorb more Vitamin D.

This is true.

So, the reasoning behind the theory is that we are all very close together, genetically, so there isn’t really any problem with mixing us all together, and pretty much, race is a social construct.

Race is a social construct of a biological reality. OoA is based on solid evidence. Just because ‘we are close together, genetically’, as egalitarians would say, doesn’t mean we should destroy the human diversity we currently have.

Much damage to evolutionary research was done by the Jew Stephen Jay Gould3, who argued in favor of the idea of rapid evolution

This is bullshit. Stephen J. Gould and Niles Eldredge proposed Puncuated Equilibria (PE). PE occurs when a species becomes as ‘adapted’ to its environment as possible and then remains in stasis. Species speciate when the environment changes (climate), or, say an earthquake occurs and splits a population of 100 peacocks in half. Fifty of the peacocks will change due to drift, natural and sexual selection. But if the environmental conditions stay the same then species cannot change.

Punctuated Equlibria is an alternative to phyletic gradualism.

What is punctuated equilibrium? What is macroevolution? A response to Pennell et al

The proposal was that after a long time in stasis that quick speciation would occur—that would be in response to the environmental change that drives the evolution of species.

He also made much damage to the field of sociobiology, literally arguing that evolution has no role in human behavior

He argued that many functions of the ‘higher’ functions of the human brain evolved for other reasons and were coopted for other reasons, which is why he coined the term ‘exaptation’.

And the debate about spandrels—which is a phenotypic trait that is a byproduct of the evolution of another trait and not due to adaptive selection. There is a tendency to assume that all—or most—traits are due to adaptive selection. This is not true.

 PZ Myers – Bad Biology: How Adaptationist Thinking Corrupts Science

With this new discovery of prehumans in Europe, they are dating the European fossil as older, but we would basically end up with the same conclusions with regards to rapid evolution and thus “race not existing.” So I don’t see anything for racists to get all excited about, with the way it is currently being presented.

Punctuated Equilibria is a lot more nuanced than you’re making it out to be. It’s looking at the whole entire fossil record and noticing that for most of a species’ evolutionary history that it remains in stasis and that evolution then occurs in quick bursts.

This theory postulates that Africans, Asians, Europeans and Aboriginal Australians all evolved completely separately from different hominidae

This is not tenable. This isn’t even how it works. Neanderthals and Homo sapiens are derived from Heidelbergensis.

Erectus is in our family tree beginning 2 mya. He is an origin of AMH and us as well. However, what you’re talking about needs to be proven with genetic testing.

Africans of course are more violent (and larger) not so much because of IQ, but because of higher levels of testosterone, but no one has explained what caused this.

Claims about substantially higher levels of testosterone in blacks are not true.

Then, of course, the Asians who moved north developed higher IQs and lighter skin because of climate-related reasons.

East Asians needed bigger brains for expertise capcity; not IQ. Light skin did evolve for climatic reasons; not sexual selection as some claim.

People need to 1) learn the basics of evolutionary theory; 2) learn the basics of the OoA hypothesis; 3) stop jumping to conclusions based on little evidence and large conjecture; 4) never trust anything at face value; always do more research into something and put all ideas under intense scrutiny, even ones you strongly believe. That way, articles like the ones above don’t get writtent with complete disregard for modern-day evolutionary theory.

John Hawks, paleoanthropologist writes:

Here’s what I think: Paleoanthropology must move past the point where a mandibular fragment is accepted as sufficient evidence.

He also states that this may be a case of apes evolving “supposed hominin characters” in the Miocene, citing a study by him and his colleagues showing that features that supposedly link Ardipethicus and Sahelanthropus are also found in other Miocene fossils (Wolpoff et al, 2006). Graecopithecus shares few features with Australopithecus, so Hawks says that we should begin to think about the possibility of Graecopithecus being “part of a diversity of apes that are continuous across parts of Africa and Europe.”

Finally, there is not enough evidence to back the claim that humans originated in Europe. Vertebrate paleontologist and paleobiologist Dr. Julian Benoit states that the author’s claim of the fourth molar root in Graecopithecus being similar to hominins is unfounded because “This is not a character that is conventionally used in palaeoanthropology, especially because not all hominins have similar tooth roots. This character is rather variable – and the authors go on to acknowledge this – so it’s unreliable for classification.” Further, humans aren’t the only apes with small canines and the jawbone and teeth aren’t too well preserved.

We have found thousands of hominin fossils in Africa. We know that the LCA between apes and humans existed between 6-12 mya in Africa. Graecopithecus was probably an ape species not related to humans. Even if the claim were true, it wouldn’t completely disprove the hypothesis that Man originated in Africa. Extraordinary claims require extraordinary evidence; this is not it.

People need to stop letting their biases and political beliefs get in the way of rational thought. Never take claims at face value; always look at things objectively. There needs to be a lot more evidence for the claim that Man originated in Europe; and even then, there is a mountain of evidence that anatomically modern humans arose in Africa.

In order to prove that Graecopithecus was a hominin and not another species of non-human ape, more fossils need to be found and a phylogenetic analysis needs to be done on the jawbone, comparing it with other species to see the closest relationship on the phylogeny. I assume when this is done it will show that it is related to non-human apes; not humans. Nevertheless, extraordinary claims require extraordinary evidence and people need to stop believing and agreeing with everything that ‘agrees’ with their worldviews as a fact without taking an objective look at the data. Never trust claims and always attempt to verify that what someone claims has a basis in reality. Only ask yourself what the facts are and what they show—without bias.

Dinosaurs, Brains, and ‘Progressive Evolution’

1800 words

Would dinosaurs have reached human-like intellect had the K-T extinction (an asteroid impact near the Yucatan peninsula) not occurred? One researcher believes so, and he believes that a dinosaur called the troodon would have evolved into a bipedal, human-like being. This is, of course, the old progressive evolution shtick. This assumes that a man-like being is an inevitability, and that sentience is a forgone conclusion.

This belief largely comes from Rushton’s citation of one Dale Russel, the discoverer of the dinosaur the troodon:

Paleontologist Dale Russell (1983,1989) quantified increasing neurological complexity through 700 million years of Earth history in invertebrates and vertebrates alike. The trend was increasing encephalization among the dinosaurs that existed for 140 million years and vanished 65 million years ago. Russell (1989) proposed that if they had not gone extinct, dinosaurs would have progressed to a large-brained, bipedal descendent. For living mammals he set the mean encephalization, the ratio of brain size to body size, at 1.00, and calculated that 65 million years ago it was only about 0.30. Encephalization quotients for living molluscs vary between 0.043 and 0.31, and for living insects between 0.008 and 0.045 but in these groups the less encephalized living species resemble forms that appeared relatively early in the geologic record, and the more encephalized species resemble those that appeared later. (Rushton, 1997: 294)

This argument is simple to rebut. What is being described is complexity. The simplest possible organism are bacteria, which reside at the left wall of complexity. The left wall “induces right-skewed distributions”, whereas the right wall induces “left-skewed distributions” (Gould, 1996: 55). Knowing this, biological complexity is a forgone conclusion, which exists at the extreme end of the right tail curve. I’ve covered this in my article Complexity, Walls, 0.400 Hitting and Evolutionary “Progress”

Talking about what Troodons may have looked like (highly, highly, doubtful. The anthropometric bias was pretty strong) is a waste of time. I’ve stated this a few times and I’ll state it yet again: without our primate body plan, our brains are pretty much useless. Our body needs our brain; our brain needs our body. Troodons would have stayed quadrupedal; they wouldn’t have gone bipedal.

He claims that some dinosaurs would have eventually reached an EQ of humans—specifically the troodon. They had EQs about 6 times higher than the average dinosaur, had fingers to grasp, had small teeth, ate meat, and appeared to be social. Dale Russel claims that had the K-T extinction not occurred, the troodon would look similar to us with a brain size around 1100 cc (the size of erectus before he went extinct). This is what he believes the dinosauroid troodon would look like had they not died out 65 mya:


When interviewed about the dinosauroid he imagined, he stated:

The “dinosauroid” was a thought experiment, based on an observable, general trend toward larger relative brain size in terrestrial vertebrates through geologic time, and the energetic efficiency of an upright posture in slow-moving, bipedal animals. It seems to me that such speculation remains acceptable, particularly if directed toward non-anthropoid anatomical configurations. However, I very nearly decided not to publish the exercise because of the damaging effects it might have had on the credibility of my work in general. Most people remained polite, although there were hostile reactions from those with “ultra-quantitative” and “ultra-intuitive” world views.

Why does it look so human? Why does he assume that the ‘ideal body plan’ is what we have? It seems to be extremely biased towards a humanoid morphology, just as other reconstructions are biased towards what we think about certain areas today and how the people may have looked in our evolutionary past. Anthropocentric bias permeates deep in evolutionary thinking, this is one such example.

Thinking of this thought experiment of a possible ‘bipedal dinosauroid’ we need to be realistic in terms of thinking of its anatomy and morphology.

Let’s accept Russel’s contention as true; that troodontids or other ‘highly encephalized species’ reached a human EQ, as he notes, of 9.4, with troodontids at .34 (the highest), archaeopteryx at .32, triconodonts (early extinct mammal of the cretaceous) with a .29 EQ, and the diademodon with an EQ of .20 (Russel, 1983). Russel found that the troodontids had EQs 6 times higher than the average dinosaur, so from here, he extrapolated that the troodon would have had a brain our size. However, Stephen Jay Gould argued the opposite in Wonderful Life writing:

If mammals had arisen late and helped to drive dinosaurs to their doom, then we could legitimately propose a scenario of expected progress. But dinosaurs remained dominant and probably became extinct only as a quirky result of the most unpredictable of all events—a mass dying triggered by extraterrestrial impact. If dinosaurs had not died in this event, they would probably still dominate the large-bodied vertebrates, as they had for so long with such conspicuous success, and mammals would still be small creatures in the interstices of their world. This situation prevailed for one hundred million years, why not sixty million more? Since dinosaurs were not moving towards markedly larger brains, and since such a prospect may lay outside the capability of reptilian design (Jerison, 1973; Hopson, 1977), we must assume that consciousness would not have evolved on our planet if a cosmic catastrophe had not claimed the dinosaurs as victims. In an entirely literal sense, we owe our existence, as large reasoning mammals, to our lucky stars. (Gould, 1989: 318)

If a large brain was probably outside of reptilian design, then a dinosaur—or a descendant (troodon included)—would have never reached human-like intelligence. However, some people may say that dinosaur descendants may have evolved brains our size since birds have brains that lie outside of reptilian design (supposedly).

However, one of the most famous fossils ever found, archaeopteryx, was within reptilian design, having feathers and along with wings which would have been used for gliding (whether or not they flew is debated). Birds descend from therapods. Anchiornis, and other older species are thought to be the first birds. Most of birds’ traits, such as bipedal posture, hinged ankles, hollow bones and S-shaped neck in birds are derived features from their ancestors.

If we didn’t exist, then if any organism were to come close to our intelligence, I would bet that some corvids would, seeing as they have a higher packing density and interconnections compared to the “layered mammalian brain” (Olkowicz et al, 2016). Nick Lane, biochemist and author of the book The Vital Question: Evolution and the Origins of Complex Life believes a type of intelligent ocotopi may have evolved, writing:

Wind back the clock to Cambrian times, half a billion years ago, when mammals first exploded into the fossil record, and let it play forwards again. Would that parallel be similar to our own? Perhaps the hills would be crawling with giant terrestrial octopuses. (Lane, 2015: 21)

We exist because we are primates. Our brains are scaled-up primate brains (Herculano-Houzel, 2009). Our primate morphology—along with our diet, sociality, and culture—is also why we came to take over the world. Our body plan—which, as far as we know, only evolved once—is why we have the ability to manipulate our environment and use our superior intelligence—which is due to the number of neurons in our cerebral cortex, the highest in the animal kingdom, 16 billion in all (Herculano-Houzel, 2009). Why postulate that a dinosaur could have looked even anywhere close to us?

This is also ignoring the fact that decimation and diversification also ‘decide the fates’ so to speak, of the species on earth. Survival during an extinction event is strongly predicated by chance (and size). The smaller an organism is, the more likely it will survive an extinction event. Who’s to say that the troodon doesn’t go extinct due to an act of contingency, say, 50 mya if the K-T extinction never occurred?

In conclusion, the supposed ‘trend’ in brain size evolution is just random fluctuations—inevitabilities since life began at the left wall of complexity. Gould wrote about a drunkard’s walk in his book Full House (Gould, 1996) in which he illustrates an example of a drunkard walking away from a bar with the bar wall being the left wall of complexity and the gutter being the right wall. The gutter will always be reached; and if he hits the wall, he will lean against the wall “until a subsequent stagger propels him in the other direction. In other words, only one direction of movement remains open for continuous advance—toward the gutter” (Gould, 1996: 150).

I bring up this old example to illustrate but one salient point: In a system of linear motion structurally constrained by a wall at one end, random movement, with no preferred directionality whatever, will inevitably propel the average position away from a starting point at the wall. The drunkard falls into the gutter every time, but his motion includes no trend whatever toward this form of perdition. Similarly, some average or extreme measure of life might move in a particular direction even if no evolutionary advantage, and no inherent trend, favor that pathway (Gould, 1996: 151).

We humans are lucky we are here. Contingencies of ‘just history’ are why we are here, and if we were not here—if the K-T extinction never occurred—and the troodon or another dinosaur species survived to the present day, they would not have reached our ‘level’ of intelligence. To believe so is to believe in teleological evolution—which certainly is not true. Anthropometric bias runs deep in evolutionary biology and paleontology. People assume that since we are—according to some—the ‘pinnacle’ of evolution, that us, or something like us, would eventually have evolved.

Any ‘trends’ can be explained as life moving away from the left wall of complexity, with the left wall—the mode of life, the modal bacter-–being unchanged. We are at the extreme tail of the distribution of complexity while bacteria are at the left wall. Complex life was inevitable since bacteria, the most simple life, began at the left wall. And so, these ‘trends’ in brain size are just that, increasing complexity, not any type of ‘progressive evolution’. Evolution just happens, natural selection occurs based on the local environment, not any inherent or intrinsic ‘progress’.


Gould, S. J. (1989). Wonderful life: the burgess Shale and the nature of history. New York: Norton.

Gould, S. J. (1996). Full house: The Spread of Excellence from Plato to Darwin. New York: Harmony Books.

Herculano-Houzel, S. (2009). The human brain in numbers: a linearly scaled-up primate brainFrontiers in Human Neuroscience,3. doi:10.3389/neuro.09.031.2009

Lane, N. (2015). The vital question: energy, evolution, and the origins of complex life. New York: W.W. Norton & Company.

Olkowicz, S., Kocourek, M., Lučan, R. K., Porteš, M., Fitch, W. T., Herculano-Houzel, S., & Němec, P. (2016). Birds have primate-like numbers of neurons in the forebrain. Proceedings of the National Academy of Sciences,113(26), 7255-7260. doi:10.1073/pnas.1517131113

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

Russell, D. A. (1983). Exponential evolution: Implications for intelligent extraterrestrial life. Advances in Space Research,3(9), 95-103. doi:10.1016/0273-1177(83)90045-5

Traumatic Brain Injury and IQ

1900 words

What is the relationship between traumatic brain injury (TBI) and IQ? Does IQ decrease? Stay the same? Increase? A few studies have looked at the relationship between TBI and IQ, and the results may be quite surprising to some. Tonight I will look through a few studies and see what the relationship is between TBI and IQ—does IQ decrease substantially or is there only a small decrease? Does it decrease for all subtests or only some?

TBI and IQ

In a sample of 72 people with TBI who had significant brain injuries had an average IQ of 90 (study 1; Bigler, 1995). Bigler also says that whatever correlation exists between brain size and IQ “does not persist post injury” (pg 387). This finding has large implications: can there be a minimal hit to IQ depending on age/severity of injury/brain size/education level?

As will be seen when I review another study on IQ and brain injury, every individual in the cohort in Bigler (1995) was tested after 42 days of brain injury. This does matter, as I will get into below.

Table 1 in study 1 shows that whatever positive relationship between IQ and brain size that is there before injury does not persist after injury (Bigler, 1995: 387). Study 1 showed that, even with mild-to-severe brain damage, there was little change in measured IQ—largely because the correlation between brain size and IQ is .51 at the high end (which I will use—the true correlation is between .24 [Pietschnig et al, 2015] to .4 [Rushton and Ankney, 2009]), this means that if the correlation were to be that high, brain size would only explain 25 percent of the variation in IQ (Skoyles, 1999). That leaves a lot of room for other reasons for differences in brain size and IQ in individuals and groups.

In study 2 (Bigler, 1995: 389-391), he looked into whether or not there were differences in IQ between high and low brain volume people (95 men). Results summed in table 3 (pg 390). Those with low brain volume (1185), aged 28, had an IQ of 82.61 while those with high brain volume (1584), aged 34 had an IQ of 92 (both cohorts had similar education). Bigler showed in study 1 IQ was maintained post injury, so we can say that this was their IQ preinjury.

In table 2, Bigler (1995) compares IQs and brain volumes of mild-to-moderate and moderate-to-severe individuals with TBI. Brain volume in the moderate-to-severe group was 1289.2 whereas for the mild-to-moderate TBI-suffering individuals had a mean brain volume of 1332.9. Amazingly, both groups had IQ scores in the normal range (90.0 for moderate-to-severe TBI and 90.7 for individuals suffering from mild-to-moderate TBI. In study 3, Bigler (1995) shows that trauma-induced atrophic changes in the brain aren’t related to IQ postinjury, nor to the amount of focal lesion volume.

Nevertheless, Bigler (1995) shows that those with bigger brains had less of a cognitive hit after TBI than those with smaller brains. PumpkinPerson pointed me to a study that shows that TBI stretches far back into our evolutionary history, with TBI seen in australopithecine fossils along with erectus fossils found throughout the world. This implies that TBI was a driver for brain size (Shivley et al, 2012); if the brain is bigger, then if/when TBI is acquired, the cognitive hit will be lessened (Stern, 2002). This is a great theory for explaining why we have large brains despite the negatives that come with them—if we were to acquire TBI in our evolutionary past, then the hit to our cognition would not be too great, and so we could still pass our genes to the next generation.

The fact that changes in IQ are minimal when brain damage is acquired shows that brain size isn’t as important as some brain-size-fetishists would like you to believe. Though, preinjury (PI) IQ was not tested, I have one study where it was.

Wood and Rutterford (2006) showed results similar to Bigler (1995)—minimal change to IQ occurs after TBI. The whole cohort pre-injury (PI) had a 99.79 IQ. T1 (early measure) IQ for the cohort was 90.96 while T2 (late measure) IQ for the cohort was 92.37. For people with greater than 11th-grade education (n=30), IQ decreased from 106.57 PI to 95.19 in T1 to 100.17 in T2. For people with less than an 11th-grade education (n=44), IQ PI was 95.16 and decreased to 86.99 in T1 and increased to 87.96 in T2. Male (n=51) and female (n=23) were similar, with male PI IQ being 99.04 to women’s 101.44 with a 90.13 IQ in T1 for men with a 90.72 IQ in T1 for women. In T2 for men it was 92.94 and for women, it was 92.83. So this cohort shows the same trends as Bigler (1995).

The most marked difference in subtests post-injury was in vocabulary (see table 3) with similarities staying the same, and digit symbol, and block design increasing between T1 and T2. Neither group differed between T1 and T2. The only significant association in performance change over time was years of education. Less educated people were at greater risk for cognitive decline (see table 2).

The difference for PI IQ after T2 for less educated people was 7.2 whereas for more educated people it was 6.4. Though more educated people gained back more IQ points between T1 and T2 (4.98 points) compared to less educated people (.97 IQ points). And: “The participants in our study represent a subgroup of patients with severe head injury reported in a larger study assessing long‐term psychosocial outcome.

Bigler (1995) didn’t have PI IQ, but Wood and Rutterford (2006) did, and from T1 to T2 (Bigler 1995 tested what would be equivalent to T1 in the Wood and Rutterford 2006 study), IQ hardly increased for those with lower education (.97 points) but substantially increased for those with higher education (4.98 points) with there being a similar difference between PI IQ and T2 IQ for both groups.

Brain-derived neurotrophic protective factor (BDNF) also promotes survival and synaptic plasticity in the human brain (Barbey et al, 2014). They genotyped 156 Vietnam War soldiers with frontal lobe lesion and “focal penetrating head injuries” for the BDNF polymorphism. Though they did find differences in the groups with and without the BDNF polymorphism, writing that there were “substantial average differences between these groups in general intelligence (≈ half a standard deviation or 8 IQ points), verbal comprehension (6 IQ points), perceptual organization (6 IQ points), working memory (8 IQ points), and processing speed (8 IQ points) after TBI” (Barbey et al, 2014). This supports the hypothesis that BDNF is protective against TBI; and since BDNF was important in our evolutionary history which is secreted by the brain while endurance running (Raichlen and Polk, 2012), this could have also been another protective factor against hits to cognition that were acquired, say, during hunts or fights.

Nevertheless, one study found in a sample of 181 children Crowe et al (2012) found that children with mild-to-moderate TBI had IQ scores in the average range, whereas children with severe TBI had IQ scores in the low average range (80 to 90; table 3).

Infants with mild TBI had IQ scores of 99.9 (n=20) whereas infants with moderate TBI has IQs of 98.0 (n=23) and infants with severe TBI had IQs of 90.7 (n=7); preschoolers with mild TBI had IQ scores of 103.8 (n=11), whereas preschoolers with moderate TBI had IQ scores of 100.1 (n=19) and preschoolers with severe TBI had IQ scores of 85.8 (n=13); middle schoolers with mild TBI had IQ scores of 93.9 (n=10), whereas middle schoolers with moderate TBI had IQ scores of 93.5 (n=21), and middle schoolers with severe TBI had IQ scores of 86.1 (n=14); finally, children with mild TBI in late childhood had a mean FSIQ of 107.3 (n=17), while children with moderate TBI had IQs of 99.5 in late childhood (n=15), and children with severe TBI in late childhood had FSIQs of 94.7 (Crowe et al, 2012; table 3). This shows that age of acquisition and severity influence IQ scores (along with their subtests), and that brain maturity matters for maintaining average intelligence post-TBI. Königs et al (2016) also show the same trend; the outlook is better for children with mild TBI, while children faired far worse with severe TBI compared to mild when compared to adults (also seen in Crowe et al, 2012).

People who got into motor vehicle accidents suffered a loss of 14 IQ points (n=33) after being tested 20 months postinjury (Parker and Rosenblum, 1996). The WAIS-IV Technical and Interpretive Manual also shows a similar loss of 16 points (pg 111-112), however, the 22 subjects were tested within 6 to 18 months within acquiring their TBI, with no indication of whether or not a follow-up was done. IQ will recover postinjury, but education, brain size, age, and severity all are factors that contribute to how many IQ points will be gained. However, adults who suffer mild, moderate, and severe TBIs have IQs in the normal range. TBI severity also had a stronger effect on children aged 2 to 7 years of age at injury, with white matter volume and results on the Glasgow Coma Scale (which is used to assess consciousness after a TBI) were related to the severity of the injury (Levin, 2012).


TBI can occur with a minimal hit to IQ (Bigler, 1995; Wood and Rutterford, 2006; Crowe et al, 2012). IQs can still be in the average range at a wide range of ages/severities, however the older one is when they suffer a TBI, the more likely it is that they will incur little to no loss in IQ (depending on the severity, and even then they are still in the average range). It is interesting to note that TBI may have been a selective factor in our brain evolution over the past 3 million years from australopithecines to erectus to Neanderthals to us. However, the fact that people with severe TBI can have IQ scores in the normal range shows that the brain size/IQ correlation isn’t all it’s cracked up to be.


Barbey AK, Colom R, Paul E, Forbes C, Krueger F, Goldman D, et al. (2014) Preservation of General Intelligence following Traumatic Brain Injury: Contributions of the Met66 Brain-Derived Neurotrophic Factor. PLoS ONE 9(2): e88733.

Bigler, E. D. (1995). Brain morphology and intelligence. Developmental Neuropsychology,11(4), 377-403. doi:10.1080/87565649509540628

Crowe, L. M., Catroppa, C., Babl, F. E., Rosenfeld, J. V., & Anderson, V. (2012). Timing of Traumatic Brain Injury in Childhood and Intellectual Outcome. Journal of Pediatric Psychology,37(7), 745-754. doi:10.1093/jpepsy/jss070

Green, R. E., Melo, B., Christensen, B., Ngo, L., Monette, G., & Bradbury, C. (2008). Measuring premorbid IQ in traumatic brain injury: An examination of the validity of the Wechsler Test of Adult Reading (WTAR). Journal of Clinical and Experimental Neuropsychology,30(2), 163-172. doi:10.1080/13803390701300524

Königs, M., Engenhorst, P. J., & Oosterlaan, J. (2016). Intelligence after traumatic brain injury: meta-analysis of outcomes and prognosis. European Journal of Neurology,23(1), 21-29. doi:10.1111/ene.12719

Levin, H. S. (2012). Long-term Intellectual Outcome of Traumatic Brain Injury in Children: Limits to Neuroplasticity of the Young Brain? Pediatrics, 129(2), e494–e495.

Parker, R. S., & Rosenblum, A. (1996). IQ loss and emotional dysfunctions after mild head injury incurred in a motor vehicle accident. Journal of Clinical Psychology,52(1), 32-43. doi:10.1002/(sici)1097-4679(199601)52:1<32::aid-jclp5>;2-1

Pietschnig, J., Penke, L., Wicherts, J. M., Zeiler, M., & Voracek, M. (n.d.). Meta-Analysis of Associations Between Human Brain Volume And Intelligence Differences: How Strong Are They and What Do They Mean? SSRN Electronic Journal. doi:10.2139/ssrn.2512128

Raichlen, D. A., & Polk, J. D. (2012). Linking brains and brawn: exercise and the evolution of human neurobiology. Proceedings of the Royal Society B: Biological Sciences,280(1750), 20122250-20122250. doi:10.1098/rspb.2012.2250

Rushton, J. P., & Ankney, C. D. (2009). Whole Brain Size and General Mental Ability: A Review. The International Journal of Neuroscience, 119(5), 692–732.

Shively, S., Scher, A. I., Perl, D. P., & Diaz-Arrastia, R. (2012). Dementia Resulting From Traumatic Brain Injury: What Is the Pathology? Archives of Neurology, 69(10), 1245–1251.

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

Stern, Y. (2002). What is cognitive reserve? Theory and research application of the reserve concept. Journal of the International Neuropsychological Society,8(03), 448-460. doi:10.1017/s1355617702813248

Wood, R. L., & Rutterford, N. A. (2006). Long‐term effect of head trauma on intellectual abilities: a 16‐year outcome study. Journal of Neurology, Neurosurgery, and Psychiatry, 77(10), 1180–1184.

Homo Erectus in America?

1800 words

Note: This article is high speculation based on the finding that occurred last week of the modification of mastodon bones in Ice Age California. If it is an actual archaeological site, along with being the age it’s purported to be, there are, in my opinion, only two possibilities for who could be responsible: erectus or the Denisova. Though I will cover evidence that Erectus did make it to America between 40-130,000ya, and rule out that Neanderthals are the hominid responsible.

It was discovered last week that there was human activity at an archeological site in San Diego, California, dated to about 130,000 years ago. Researchers discovered pieces of bone and teeth from a mastodon—that looked to have been modified by early humans. This discovery—if it shows that there was a hominid in the Americas 130,000ya—would have us rethink hominin migrations in the ancient past.

The bones and teeth show signs of having been modified by humans with “manual dexterity and experiential knowledge.” The same pattern was discovered in Nebraska and Kansas, where it was ruled out that carnivorous animals were responsible (Holen et al, 2017).

Now, we only have a few pieces of broken bone and some teeth from a mastodon. It is possible that ‘Natives’ dug up the mastodon skull and modified it, but I like to think outside of the box sometimes. When I first read the ScienceDaily article on the matter, the first hominin that popped into my head that could be responsible for this is erectus. But what is the evidence that he could have made it to the Americas that long ago?

Erectus in America

Evidence for erectus in America is scant. We have discovered no erectus skeletons in the Americas, and we only have a few pieces of bone to go off of to guess which hominid did this (and I doubt it was Homo sapiens or Neanderthals, I will explain my reasoning below).

I’ve been documenting on my blog for the past six months that, contrary to popular belief, erectus was not a ‘dumb ape’ and that, in fact, erectus had a lot of modern behaviors. If it turns out to be true that erectus made it to America, that wouldn’t really surprise me.

erectus map

—Erectus territory


–Neanderthal territory

Erectus had a wider territory than the other hominid candidates (Neanderthals, Homo sapiens) and the other candidate—the Denisova—were situated more to the middle of the Asian continent. So this, really, leaves us only with erectus as the only possible candidate for the mysterious hominin in Caliofornia—and there is evidence that (albeit, extremely flimsy), erectus may have possibly made it to America, from a paper published back in 1986. Dreier (1986) writes that there is evidence of Man in America before 30kya, and if this is true, then it must be erectus since the estimated dates are between 50-70 kya—right around the time that AMH began migrating out of Africa. Dreier (1986) goes through a few different discoveries that could have been erectus in America, yet they were only modern skeletons. However, absence of evidence is not evidence of absence. (Though I will return to this specific point near the end of the article.)

How could erectus have possibly made it to America?

This is one of the most interesting things about this whole scenario. There is evidence that erectus made rafts. If erectus did make it to Flores (Stringer, 2004; Hardaker, 2007: 263-268; Lieberman, 2013)—eventually evolving into floresiensis (or from habilis or a shared common ancestor with habilis)—then he must have had the ability to make rafts. Since we have found erectus skulls at Java, and since certain bodily proportions of floresiensis are ‘scaled-down’ from erectus, along with tools that erectus used, it’s not out of the realm of possibility that erectus had the ability to navigate the seas.

One way that hominins can get to America is through the Bering strait. However, Dreier (1986) assumes that erectus was not cold-adapted, and insists that erectus could have only gone into higher latitudes for only a few months out of the year when it was warmer. As you can see from the above map of erectus’ territory, he lived along the coast of China and into some of the islands around SE Asia. While we don’t have any skeletal evidence, we can infer that it was late Asian erectus who, could have possibly, made it to the Americas. So since it was late in erectus’ evolution, we would expect him to have a large brain size in order to 1) survive in Africa and 2) since brain size predicts the success of a species in novel environments (Sol et al, 2008), erectus would have had a larger brain in these locations. So it seems that erectus did have the same adaptability that we do—especially if he actually did make it to the Americas.

Dreier (1986) posits that erectus could have traveled along the Aluetian island chain in Alaska, eating marine life (shells, mollusks, clams, etc), and so he would not have had to “deviate from the 53 north latitude vitamin D barrier drastically since almost the entire Aleutian Island chain falls between the 50 and 55 north latitude lines, and access via this route may have been possible during glaciation when sea levels in the area dropped as much as 100 meters” (Dreier, 1986: 31). Erectus could have gotten vitamin D from shells, mollusks and other marine life, as they are extremely high in vitamin D (Nair and Maseeh, 2012). I will contend that erectus rafted to America, but the Aluetian island route is also plausible.

Dreier (1986) ends up concluding that our best bet for finding erectus skeletons in America is along with Pacific coast, and there may be some submerged underwater. However, with the new discovery last week, I await more work into the site for some more answers (and of course questions).

However, contra Dreier’s (1986) claim that we should stop looking for sites with human activity earlier than 30,000 years, this new finding is promising.

Why not Neanderthals?

Neanderthals were seafarers, just like erectus, and later, us. However, there is evidence for Neanderthals sailing the seas 100kya, however, earlier dates of seafaring activity “as far back as 200 ka BP can not be excluded.” (Ferentinos et al, 2012). Further—and perhaps most importantly—the range of the Neanderthals was nowhere near the Pacific Ocean—whereas erectus was. So since there is little evidence of seafaring 200kya (which cannot be excluded), then we’re still left with the only possibility being erectus go to the Americas either by walking the Aleutian islands or rafting across the Pacific.

Could erectus have killed animals as large as a mastodon?

Erectus was killing elephants (Elephas antiquus) around 400kya in the Levant (Ben-Dor et al, 2011). Then, when the elephants went extinct, erectus had to hunt smaller, quicker game and thus evolved a smaller body to deal with the new environmental pressure—chasing a new food source. So erectus did have the ability to kill an animal that big, another positive sign that this is erectus we are dealing with in California 130,000 years ago.

An erectus skeleton in America?

An osteologist discovered a brow bone in the Americas, and in an unpublished report in 1990, he says the brow’s thickness and structure is comparable to African erectus, with a reanalysis showing it was closer to Asian erectus—just what we would expect since Asian erectus may have been a seafarer (Hardaker, 2007). However, the author of the book reiterates the Texas A&M osteologists’ findings writing: “these comparisons do not imply that preHomo sapiens were in the Americas” (Steen-McIntyre, 2008).

Humanlike cognition in erectus?

Humanlike thinking evolved 1.8 mya, right around the time erectus came into the picture (Putt et al, 2017). Volunteers created Auchulean tools while wearing a wearing a cap that measured brain activity. Visual attention and motor control were needed to create the “simpler Oldowan tools”, whereas for the “more complex Auchelian tools” a “larger portion of the brain was engaged in the creation of the more complex Acheulian tools, including regions of the brain associated with the integration of visual, auditory and sensorimotor information; the guidance of visual working memory; and higher-order action planning.” This discovery pushes back the advent of humanlike congition, since the earliest tools of this nature are found around 1.8 mya. There is a possibility that some erectus may have had IQs near ours, as studies of microcephalics show that a large amount have higher than average IQs (Skoyles, 1999).


Evidence is mounting that erectus was more than the ‘dumb ape’ that some people say he is. If erectus did make it to America—and the possibility is there—then human migratory patterns need to be rewritten. I hope there is more evidence pointing to what hominid was in the area at that time—and if there is evidence of humanlike activity there, it most likely is erectus. It is extremely possible that erectus could have gotten to America, as there is evidence that he was at least in northern China. So he could have sailed to the Americas or walked along the Aluetian islands.

The evidence for erectus in America is compelling, and I hope more is discovered about what went on at this site and who was there. Even if it wasn’t erectus, there is still some compelling evidence that he did make it to America.


Ben-Dor, M., Gopher, A., Hershkovitz, I., & Barkai, R. (2011). Man the Fat Hunter: The Demise of Homo erectus and the Emergence of a New Hominin Lineage in the Middle Pleistocene (ca. 400 kyr) Levant. PLoS ONE,6(12). doi:10.1371/journal.pone.0028689

Dreier, Frederick G., (1986). Homo Erectus in America: Possibilities and problems. Lambda Alpha Journal of Man, v.17, no.1-2, 1985-1986. Citing: Gifford, E.W., (1926). California Anthropometry. University of California Publications in Archaeology and Ethnology.22:217-390

Ferentinos, G., Gkioni, M., Geraga, M., & Papatheodorou, G. (2012). Early seafaring activity in the southern Ionian Islands, Mediterranean Sea. Journal of Archaeological Science,39(7), 2167-2176. doi:10.1016/j.jas.2012.01.032

Hardaker, C. (2007). The first American: the suppressed story of the people who discovered the New World. Franklin Lakes, NJ: New Page Books, a division of The Career Press.

Holen, S. R., Deméré, T. A., Fisher, D. C., Fullagar, R., Paces, J. B., Jefferson, G. T., . . . Holen, K. A. (2017). A 130,000-year-old archaeological site in southern California, USA. Nature,544(7651), 479-483. doi:10.1038/nature22065

Lieberman, D. (2013). The Story of the human body – evolution, health and disease. Penguin.

Nair, R., & Maseeh, A. (2012). Vitamin D: The “sunshine” vitamin. Journal of Pharmacology & Pharmacotherapeutics, 3(2), 118–126.

Putt, S. S., Wijeakumar, S., Franciscus, G. R., Spencer. P. J. The functional brain networks that underlie Early Stone Age tool manufacture. Nature Human Behaviour, 2017

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

Sol, D., Bacher, S., Reader, S., & Lefebvre, L. (2008). Brain Size Predicts the Success of Mammal Species Introduced into Novel Environments. The American Naturalist,172(S1). doi:10.1086/588304

Steen-McIntyre, V. (2008) A Review of the Valsequillo, Mexico Early-Man Archaeological Sites (1962-2004) with Emphasis on the Geological Investigations of Harold E. Malde. Presentation at 2008 Geological Society of America Joint Annual Meeting Oct. 5-9, Houston, Texas

Stringer, C. (2004, October 27). A stranger from Flores. Retrieved May 09, 2017, from

The Evolutionary Puzzle of Floresiensis

1600 words

Back in October, I wrote that floresiensis is either descended from Erectus or habilis, since those were the only two hominins in the region. Yesterday a study was published titled The affinities of Homo floresiensis based on phylogenetic analyses of cranial, dental, and postcranial characters (Argue et al, 2017), in which Argue et al argue that floresiensis was not descended from a shipwrecked Erectus, as is a popular view. Another theory is that floresiensis is descended from habilis. The third theory is that floresiensis is Homo sapiens with a pathology, but that has been disproven (Falk et al, 2009). It was commonly thought that the LB1 floresiensis specimen was a pathological human inflicted with Laron syndrome which is a type of growth hormone deficiency (Laron and Klinger, 1994).

Argue et al found that floresiensis and erectus had completely different bone structures, particularly in the pelvis and jaw. They now believe that the theory that floresiensis is a derived form of an erectus that swam or rafted to Flores has been defintively refuted. They found that floresiensis was a sister species to habilis. So either a common ancestor of floresiensis or habilis swam to Flores from Africa, or floresiensis evolved in Africa and swam to Flores. They used new phylogenetic techniques to ascertain that floresiensis is stil a part of our lineage, but shows no phylogenetic relationship to erectus on the tree.

According to Baab (2016), biogeography shows that Indonesian erectus is the best fit with what is currently known. She says if floresiensis was derived from erectus that it “implies some degree of body size reduction and more marked brain size reduction.”

Kubo, Kono, and Kaifu (2013) conclude that the evolution of floresiensis from early Javanese erectus is possible when comparing the brain cases of both specimens. However, if floresiensis descended from habilis, then the brain size reduction wouldn’t be as marked (and is still due to island dwarfism, just not on as large of a scale as it would be if floresiensis were descended from erectus). The LB1 specimen also shows the closest neural affinities to early Asian erectus (Baab, Mcnulty, and Harvati, 2013; but see Vannuci, Barron, and Holloway, 2013 for the microcephalic view). Weston and Lister, (2009) showed that there was a 30 percent reduction in brain size in Magalasy hippos, which lends credence to the insular dwarfism hypothesis for floresiensis. Craniofacial morphology also shows that floresiensis evolved from Asian erectus (Kaifu et al, 2011).

The teeth of unknown hominin found at Mata Menge are intermediate between floresiensis and erectus, being 600,000 years older than where floresiensis was found (van den Bergh et al, 2016). This lends credence to the hypothesis that floresiensis is derived from erectus. Furthermore, insular dwarfism is seen in primate species isolated on islands, with changes in body size seen in child populations even on large islands not far from the mainland (Bromham and Cardillo, 2007, Welch, 2009). Genetically isolated on islands, primates can become bigger if the parent population was smaller, or smaller if the parent population was bigger. This is due to differing energy demands relative to the parent population, along with differing predators/prey.

The island rule even holds in the deep sea. As is the case with islands, the deep sea is also associated with decreased food availability. Looking at several species of gastropods, McClain, Boyer, and Rosenberg (2006) found that the island rule held in small-bodied shallow species. They were found to have larger bodied deep-sea representatives, with the same being true for large bodied deep-sea gastropods. Further, island dwarfism in elephants on the islands Sicily, Malta, Cyprus; mammoths on the California channel islands; and red deer on the island Jersey involved body mass changes of 5- to 100-fold over 2,300 to 120,000 generations (Evans et al, 2012).

So the overall hypothesis that island dwarfism is still intact, albeit if floresiensis is derived from habilis, the reduction in brain/body size would be smaller than if floresiensis evolved from early Asian erectus.

Further evidence for brain/body size reduction due to less food availability is noted by Daniel Lieberman in his book The Story of the Human Body: Evolution, Health, and Disease (Lieberman, 2013). While talking about the evolution of floresiensis on page 123 he writes:

The same energetic constraints and processes also affect hunter-gatherers . 62

And in the 62nd footnote on page 391 he writes:

Several human “pygmy” populations (people whose height does not exceed 150 centimeters, or 4.9 feet) have evolved in energy limited places like rain forests or islands. Perhaps the small size of the Dmansi hominins from Georgia also reflected selection to save energy among the first colonists of Eurasia.

Either way, if floresiensis evolved from erectus or habilis, considerable reductions in brain size have to be explained, since the smallest erectus brain ever found is 600 cubic centimeters while the smallest habilis brain ever found is 510 cubic centimeters (Lieberman, 2013: 124), with floresiensis having a brain 417 cubic centimeters (Falk et al, 2007).

What is most important about the insular dwarfism hypothesis in regards to the evolution of floresiensis is the effect of energy reduction/food availability and quality in regards to populations isolated on islands from parent populations. Floresiensis was able to survive on about 1200 kcal by shrinking, needing to consume about 1400 kcal during lactation compared to 1800 kcal for an erectus female who needed about 2500 kcal during lactation (Lieberman, 2013: 125). The cognitive price for the reduction in the brain size of floresiensis is not known, but since brains are so energy expensive (Aiello and Wheeler, 1995; Herculano-Houzel and Kaas, 2011; Fonseca-Azevedo and Herculano-Houzel, 2012), the reduction seen in floresiensis is no surprise.

Energy is one of the most important drivers for the evolution of a species, the evolution of floresiensis is one major example of this. Whether floresiensis evolved from habilis or erectus, reduced energy on the island caused the brain and body size of floresiensis to get smaller to cope with fewer things to eat. Keep in mind that habilis was a meat-eater as well, and with lower-quality energy on the island, the brain would have to reduce in size as it’s one of the most expensive organs in the body. As I’ve been saying for a long time now, the quality of energy is most important to the evolution of a species—especially Man. Cooking was imperative to our evolution, and with a lower-quality diet, we, too, would evolve smaller brains and bodies to compensate for reduced energy consumption since our brains take 25 percent of our daily energy requirements to power despite being 2 percent of our overall body weight.

The evolution of floresiensis shows how important energy is in the evolution of species. Its biggest implication—no matter if floresiensis evolved from habilis or erectus—is how important diet quality is to evolution, as I’ve noted here, here, here, here, here, and here. Without our high-quality diet, we, too, would suffer the same body/brain size reductions that floresiensis did.


Aiello, L. C., & Wheeler, P. (1995). The Expensive-Tissue Hypothesis: The Brain and the Digestive System in Human and Primate Evolution. Current Anthropology,36(2), 199-221. doi:10.1086/204350

Argue, D., Groves, C. P., Lee, M. S., & Jungers, W. L. (2017). The affinities of Homo floresiensis based on phylogenetic analyses of cranial, dental, and postcranial characters. Journal of Human Evolution. doi:10.1016/j.jhevol.2017.02.006

Baab, K. L., Mcnulty, K. P., & Harvati, K. (2013). Homo floresiensis Contextualized: A Geometric Morphometric Comparative Analysis of Fossil and Pathological Human Samples. PLoS ONE,8(7). doi:10.1371/journal.pone.0069119

Baab, K.L. (2016). The place of Homo floresiensis in human evolutionJournal of Anthropological Sciences, 94, 5-18.

Bergh, G. D., Kaifu, Y., Kurniawan, I., Kono, R. T., Brumm, A., Setiyabudi, E., . . . Morwood, M. J. (2016). Homo floresiensis-like fossils from the early Middle Pleistocene of Flores. Nature,534(7606), 245-248. doi:10.1038/nature17999

Bromham, L., & Cardillo, M. (2007). Primates follow the ‘island rule’: implications for interpreting Homo floresiensis. Biology Letters,3(4), 398-400. doi:10.1098/rsbl.2007.0113

Evans AR, Jones D, Boyer AG, Brown JH, Costa DP, et al. (2012) The maximum rate of mammal evolution. Proc Natl Acad Sci USA 109: 4187–4190.

Falk, D., Hildebolt, C., Smith, K., Morwood, M. J., Sutikna, T., Jatmiko, … Prior, F. (2007). Brain shape in human microcephalics and Homo floresiensis. Proceedings of the National Academy of Sciences of the United States of America, 104(7), 2513–2518.

Falk, D., Hildebolt, C., Smith, K., Jungers, W., Larson, S., Morwood, M., . . . Prior, F. (2009). The type specimen (LB1) of Homo floresiensis did not have Laron Syndrome. American Journal of Physical Anthropology,140(1), 52-63. doi:10.1002/ajpa.21035

Fonseca-Azevedo, K., & Herculano-Houzel, S. (2012). Metabolic constraint imposes tradeoff between body size and number of brain neurons in human evolution. Proceedings of the National Academy of Sciences,109(45), 18571-18576. doi:10.1073/pnas.1206390109

Herculano-Houzel, S., & Kaas, J. H. (2011). Gorilla and Orangutan Brains Conform to the Primate Cellular Scaling Rules: Implications for Human Evolution. Brain, Behavior and Evolution, 77(1), 33–44.

Kaifu, Y., Baba, H., Sutikna, T., Morwood, M. J., Kubo, D., Saptomo, E. W., . . . Djubiantono, T. (2011). Craniofacial morphology of Homo floresiensis: Description, taxonomic affinities, and evolutionary implication. Journal of Human Evolution,61(6), 644-682. doi:10.1016/j.jhevol.2011.08.008

Kubo, D., Kono, R. T., & Kaifu, Y. (2013). Brain size of Homo floresiensis and its evolutionary implications. Proceedings of the Royal Society B: Biological Sciences,280(1760), 20130338-20130338. doi:10.1098/rspb.2013.0338

Laron, Z., & Klinger, B. (1994). Laron Syndrome: Clinical Features, Molecular Pathology and Treatment. Hormone Research,42(4-5), 198-202. doi:10.1159/00018419

Lieberman, D. (2013). The Story of the human body – evolution, health and disease. Penguin.

Mcclain, C. R., Boyer, A. G., & Rosenberg, G. (2006). The island rule and the evolution of body size in the deep sea. Journal of Biogeography,33(9), 1578-1584. doi:10.1111/j.1365-2699.2006.01545.x

Vannucci, R. C., Barron, T. F., & Holloway, R. L. (2011). Craniometric ratios of microcephaly and LB1, Homo floresiensis, using MRI and endocasts. Proceedings of the National Academy of Sciences of the United States of America, 108(34), 14043–14048.

Welch, J. J. (2009). Testing the island rule: primates as a case study. Proceedings of the Royal Society B: Biological Sciences,276(1657), 675-682. doi:10.1098/rspb.2008.1180

Weston, E. M., & Lister, A. M. (2009). Insular dwarfism in hippos and a model for brain size reduction in Homo floresiensis. Nature, 459(7243), 85–88.

Evolution and IQ Linkfest IV

1050 words

A decorated raven bone discovered in Crimea may provide insight into Neanderthal cognition (A raven bone discovered in Crimea shows two extra notches, which the researchers say they did intentionally to create a consistent—perhaps symbolic—pattern.)

Just like humans, artificial intelligence can be sexist and racist (Just like Tay. RIP in peace, Tay. Princeton University academics have shown, using a database of over 840 billion words from the Internet, that AI mimics humans and, they too, can apparently become ‘racist and sexist’, just like their creators. A “bundle of names” being associated with European Americans were more likely to be associated with pleasant terms, compared to African Americans who were associated with unpleasant terms. Male names were associated with careers while female names were associated with family. Seems like the AI just gets information and makes a conclusion based on the information, learning as it goes along. I don’t think putting human buzzwords onto AI is practical.)

Childhood lead exposure linked to lower adult IQ (This has been known for, literally, decades. In the new study, every 5 micrograms/dl increase in blood lead levels early in life was shown to decrease IQ by 1.61 points by the time the subjects reached 38 years of age along with reductions in working memory and perceptual reasoning. More shockingly, children who had blood lead levels over 10 micrograms/dl had IQs 4.25 points lower than their peers with low blood lead levels. Some research has shown that for each decrease in 1 point decrease in IQ annual salary decreases by about 200 to 600 dollars. This also shows that high blood-lead levels during childhood cannot be recovered from. There is currently an epidemic of lead poisoning in the Detroit Metropolitan area affecting Arab and African American children (Nriagu et al, 2014), as well as in low-income blacks in Saginaw, Michigan (Smith and Nriagu, 2010) and immigrant children in NYC (Tehranifar et al, 2008). However, see Koller et al (2004) for a different view, showing that blood-lead levels during childhood only account for 4 percent of the variation in cognition whereas parental and social factors account for more than 40 percent. High blood lead levels also lead to an increase in detrimental behavior (Sciarillo, Alexander, and Farrell, 1992). Clearly, measures need to be taken to reduce lead in water around the country as quality of life will improve for everyone.)

Molecular clocks track human evolution (Scientists estimate that we emerged around 200kya in Africa and spread throughout the world 50-100 kya through looking at the ‘molecular clock’—mutation and recombination. Some geneticists estimate that there are between 1.5 and 2 million mutational changes between humans and Neanderthals—estimating a splitting date at 550-750kya.)

How Ants Figured Out Farming Millions of Years Before Humans (Ants have probably been farming since the Chicxulub meteor impact that killed the dinosaurs in one South American rainforest. The researchers found that all fungus-farming ants came from the same ancestor around 60mya. Thirty million years later, another farming species emerged. One of the species was a “more complex agriculturalist” which probably transported its fungus to different locations while the other species were “lower, less complex agriculturalists” which grew fungus capable of “escaping its garden and living independently”. The dry climate allowed the more complex agriculturalists to domesticate the fungus and control the temperature by digging holes for storage.

Mimicking an impact on Earth’s early atmosphere yields all 4 RNA bases (Researchers showed that mimicking an asteroid crash resulted in the formation of the production of all four bases of RNA, the molecules essential for life. Take that, Creationists.)

Study finds some significant differences in brains of men and women (Adjusting for age, researchers found that women had significantly thicker cortices than men while men had higher brain volumes in every area they looked at, including the hippocampus (which plays a part in memory and spatial awareness), the amygdala (plays a role in memory, emotions, and decision-making), striatum (learning, inhibition, and reward-processing), and the thalamus (processing and relaying sensory information to other parts of the body). Men also varied more in cortical thickness and volume much more than women, which supports other studies showing that men only have higher IQ distributions than women, not higher average intelligence. There are, of course, differences between the male and female brain, but I’m now rethinking my position on male/female IQ differences (leaning towards no). Read the preprint here: Sex Differences In The Adult Human Brain: Evidence From 5,216 UK Biobank Participants

Infants show racial bias toward members of own ethnicity, against those of others (Now the study I’ve seen a buzz about the past few days. In one of the studies, researchers found that babies associated other races’ faces with sad music while associating their own races’ face with upbeat, happy music. The second study showed that infants were more likely to learn from their own race than another, which relied on gaze cues. Both studies tested infants between the ages of 6 to 9 months with both studies finding no racial bias in infants less than 6 months of age. The researchers, of course, conclude that this occurs because of lack of contact with other race babies/people. In study one, infants aged 3 to 10 months watched videos with a female adult with a neutral facial expression. The babies heard music before viewing each clip; happy music and same race face; happy music and opposite race face; sad music and same race face; and sad music and opposite race face. They found that babies looked longer at same-race faces with happy music while looking longer at other-race faces with sad music. The second study looked at whether or not babies would be willing to learn from their own race or a different race. Babies aged 6 to 9 months were shown a video in which a female adult appeared and looked at one of the four corners of the screen. In some of the videos, an animal appeared where the person on the screen looked while in other videos, an animal appeared at a non-looked at location. They showed that babies followed the gaze of their own race more often than the other race, showing that infants are “biased” towards learning from their own race. This is clearly evidence for Genetic Similarity Theory. Expect a research article on this soon. Read the abstracts here: Infants Rely More on Gaze Cues From Own-Race Than Other-Race Adults for Learning Under Uncertainty and Older but not younger infants associate own-race faces with happy music and other-race faces with sad music)