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Complexity, Walls, 0.400 Hitting and Evolutionary “Progress”
What do complexity, baseball and evolutionary “progress” have to do with each other? A lot. Stephen Jay Gould, in his book Full House he eloquently weaves these seemingly unrelated things into a coherent attack on so-called “progressive” evolution. Most people assume that the disappearance of 0.400 hitting is due to a decline in ability, however Gould argues that we didn’t get worse at baseball, we got better. The average stayed the same (around 0.260 a year) but the variation in the curve decreased substantially. He shows that complexity is a forgone conclusion since the simplest organisms, bacteria, are at the left side of the wall of complexity, that is the simplest organism there can be. Thusly, complex organisms aren’t driven by “progress” to become complex; the left wall of minimal complexity is “followed by successful expansion thereafter with retention of an unvarying bacterial mode.” (Gould, 1996: 196-7). Complexity is an incidental occurrence due to life’s beginnings at this left wall; no organism can become less complex than this. Complexity is not driven by “progress”.
Most people assume that 0.400 hitting has disappeared from baseball because we have gotten worse at the game. However, an alternate way of looking at it is there have been no 0.400 hitters since 1941 because we have gotten better at the game and the variation on the bell curve shrunk due to the average players getting better. A batting average between .260 and .275 has been the average for each year since the conception of the game. This shows that since the average didn’t change, the variation got smaller due to the average player becoming better.
With the right tail shrinking, this meant that the average player then became closer to the right wall, that is the wall of how good one can become (i.e., 0.400 hitting) and since the variation shrunk, both bad and good (the 0.400) batting averages disappeared due to the average player getting better and getting closer to the right wall. Since the SD of batting averages for regular players decreases steadily over time, this shows that a disappearance of 0.400 hitting is “a consequence of shrinkage at the right tail of the distribution.”(Gould, 1996: 107)
Gould sums up as follows:
In quick summary of a long and detailed argument, symmetrically shrinking deviations in batting averages must record general improvement of play (including hitting, of course) for two reasons—the first (expressed in terms of the history of the institutions) because systems manned by best performers in competition, and working under the same rules through time, slowly discover optimal procedures and reduce their variation as all personnel learn and master the best ways; the second (expressed in terms of performers and human limits) because the mean moves toward the right wall, thus leaving less space for the spread of variation. Hitting 0.400 is not a thing, but the right tail of the full house for variation in batting averages. As variation shrinks because general play improves, 0.400 hitting disappears as a consequence of increasing excellance in play. (Gould, 1996: 127-8)
The explanation of the disappearance of 0.400 hitting sets the stage for the purpose of this article: “progressive” evolution. It’s important to know that I’m not saying that organisms don’t become more “complex”, the point is, evolution is not “going” anywhere; and that there is a passive and not driven trend in the complexity of organisms. Since bacteria, the modal bacter rules the earth, can we really say that there is any “drive” towards progress? Or is complexity driven by the consequence of the simplest organisms being at the left wall, with the only way to go being “right”?
Complexity, Walls, and “Progressive” Evolution
The assumption that there is a “march of progress”, a “scala naturae”, an “evolutionary ladder of progress” for all organisms on earth is a pervasive idea. But does the fossil record show any march to “progress”? No. People assume that evolution is “progressing” and the end result is a “better” organism. However, that’s a gross misunderstanding of natural selection and what it does. Natural selection is not “progress”, but local change. Let’s take a population of 100 brown bears. Half of them split off and head north and spend 100,000 years evolving near the North Pole. Would the new species that arises be “more progressed” or “more evolved” than the brown bear? No. It has incurred local adaptations to better survive in that new environment.
Bacteria is the most abundant life form on the planet. Bacteria, which is at the very left wall of complexity, is the most simple organism that can be. Due to this, there is nowhere to go but right, to the right wall. So any organism that’s caught up in the middle of the left and right walls of complexity can go in either direction. They can become less complex or more complex depending on what the environment calls for.
Darwin himself had contradictory views on “progressive” evolution. On the one hand, Darwin stated at the end of On the Origin of Species:
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.
Darwin did write in one of his notebooks to “Never call a species higher or lower”. This shows that even the man who originated the concept of natural selection didn’t believe in “higher” and “lower” organisms. Quoting page 135 of Full House by Gould on a conversation between Huxley and Darwin (their descendants) held in 1959:
Huxley: I once tried to define evolution in an overall way, somewhat along these lines: a one way process, irreversible in time, producing apparent novelties and greater variety leading and leading to higher degrees of organization.
Darwin: What is “higher”?
Huxley: More differentiated, more complex but at the same time more integrated.
Darwin: But parasites are also produced.
Huxley: I mean a higher degree of orginization in general, as shown by the upper level attained.
Darwin asked a good question about what constitutes “higher”. Huxley gave a non-answer, an answer that confirms what he said (which isn’t true).
Any so-called “progress” would have been stymied by the five mass extinction events that have occurred throughout earth’s history. The history of life has been punctuated with mass extinction events. It was, after all, the mass extinction event at the Cretaceous period that killed off the dinosaurs that gave mammals the chance to evolve into what we did today. It was fish that mutated the beginnings of arms and wings; the precursors to what more complex organisms would use in the future. Our fish ancestor evolved that way most likely due to the fact that it could have pushed itself onto land to avoid predators. Examinations of the fossil record show that certain fishes have the precursors to arms and wings. This shows that we evolved from fish that eventually came on to land. The ONLY REASON why we are around today is because of the mass extinction event 65 mya. Without that, disnosaurs would still rule the earth. Basically, if our ancestors swam up instead of down, left instead of right, they’d have been eaten and we wouldn’t be here today. That’s not to say that there would be no right wall of complexity; there always will be, but they wouldn’t turn into us as there is no evolutionary trend in organismal design.
Numerous studies have been done on ammonites, plankton, and other small, less complex organisms. No line of “progress” was found in none of the organisms tested. There was no bias in increasing complexity from ancestor-descendant pairs in ammonites (that is, the range of variation for complexity increased, not just a drive to become more complex) (Boyajian and Lutz, 1992), nor was there any correlation for sutural complexity and geological longevity. No bias for increasing complexity was found in these organisms, that is no bias to go towards this right wall of complexity.
McShea (1994) uses this “left wall of minimal complexity”, in which there is only one way to go: right. McShea proposes three tests for seeing whether or not there is a driven or passive drive for evolution:
- Test the Minimum: In passive systems, minimal values of complexity should be preserved by some species throughout the expanding history of their evolutionary timespan because no preference for evolutionary complexity exists and most species would do better by simply staying as they are. In systems that are driven, both minimal and maximal complexity should increase because higher complexity confers general advantages that the evolution of all species should be biased in this direction (they aren’t). The preservation and continuing enhancement of the modal bacter strongly points to the passive mode for life as a whole.
- Testing Ancestor-Descendant Pairings: This test identifies ancestral lineages for an expanding lineage and then tabulates whether each concurrent species stayed the same, got simpler or got more complex. However we cannot use this test because the fossil record is so incomplete.
- Test of the Skewing: Life as a whole can produce right-skewed trends no matter if evolution is passive or driven. So the same overall result of right distribution with a maximum complexity can still occur whether or not evolution is passive or driven. In driven systems, the new lineages should show a right skew towards complexity since all species favor the right skew of “progress” as a favored direction, and should have more species towards the right wall of complexity, stretching the entire distribution to the right. But in the passive systems, there should be no skew in increases and decreases should be just as common as increases. Many species move leftward in complexity as they do rightward. If one organism is in between the right and left wall of complexity, it can go either get more or less complex, with least complex being a bacteria, that being the “left wall” of complexity.
McShea did these tests on veterbral columns. You would say “Of course there was an increase in complexity!!” But is this increase driven or passive? According to McShea (1994), vertebrates began at a minimal level of complexity, so the only way to go was UP!
Quoting Gould (1996: 207):
All the tests provide evidence for a passive trend and no drive to complexity. McShea found twenty-four cases of significant increases or decreases in comparing the range of modern descendants with an ancestor (out of a potential sample of ninety comparisons, or five groups of mammals, each with six variables measured in each of three ways; for the other comparison, average descendants did not differ significantly from ancestors). Interestingly, thirteen of these significant changes led to decreases in complexity, while only nine showed an increase. (The difference between thirteen and nine is not statistically significant, but I am wryly amused, given all traditional expectation in the other direction, that more comparisons show increasing rather than decreasing complexity.
McShea summarizes his entire study as follows (1994: 1762):
The minimal complexity of vertebral columns probably did not change (indeed, the actual minimum seems to have remained close to the theoretical minimum), ancestor-descendant comparisons in subclades of mammals reveals no branching bias, and the mean subclade skew was negative, all pointing to a passive system.
This can be summed up as follows: Looking at the “full house” of variation, there is no general trend in “progress” for organisms or evolution as a whole. The example of the disappearance of 0.400 hitting is the perfect metaphor that shows there is a left and right wall of both minimum and maximum skill (complexity) and that the variation shrunk which is the cause for the disappearance of 0.400 hitting, not us getting “worse” at the game. This same metaphor of skill walls can be used for evolution as well, replacing skill walls with complexity walls. Bacteria inhabit the very left wall of complexity, that is, the least simple organism possible; no other organism can become more simple than bacteria. On the other side, you have the more complex organisms, those that arise at the very right tail end of the distribution, but arose there due to no inherent drive for “progress”, but due to the fact of moving towards the right tail of complexity was the only thing possible to do. Any organism that is in between the left and right walls of complexity can go in either direction, and the fossil record shows more organisms going left than right.
Looking at certain variables, we may be able to say “Look!! Evolutionary progress!!” But that’s only a small snapshot in time. People may point to the brain size increase as a driven increase towards complexity, however, the assumption that there is a “relative enlargement and differentiation of brains reflect a progressive evolutionary trend toward greater intelligence is a major impediment to the study of brain evolution.” I will cover this in the future and goes against what believers of evolutionary “progress” believe. When looking at one snapshot in the huge picture of evolutionary time, we may be able to “pin point” a “progression” towards “something”, but when looking at the fossil record as a whole (which is not possible due to there being huge gaps due to punctuated equilibria, we cannot study the whole record) there is no “drive” towards complexity, it is “passive”, that is organisms become less and more complex due to variation in environments. THAT is what natural selection is and does for organisms. Natural selection is local adaptation, not evolutionary progress.
The notion of “progressive” evolution needs to be put to rest. It doesn’t allow us to fully appreciate the beauty of evolution through natural selection, mutation, genetic drift and migration. No species is “better” or “more progressed” or “more evolved” than another; on the contrary. Each oragnism is unique to its environment and will incur both genotypic and phenotypic changes that respond to what’s occurring in the environment as to better reproduce to the next generation. I will end with a quote from Gould that perfectly sums up this argument:
I hate to think that an intellectual position, hopefully well worked out in the pages of this book, might end up as a shill for one of the great fuzzinesses of our age—so-called “political correctness” as a doctrine that celebrates all indigenous practice, and therefore permits no distinctions, judgements or analyses.
Looking at the whole “full house” of variation shows there to be no trends of “progress”. Organisms are just as likely to become less complex (towards the left wall) than they are to become more complex (towards the right wall). Once we get this “scala naturae” paradigm out of our heads and understanding of evolution, only then can we appreciate the beauty and randomness of evolution and all of the differences it brings about. There IS a drive towards the right wall of complexity, however, it is not driven, it is passive and is only a result of there being a minimum wall of complexity that no other organism can get less complex than. Looking at evolution in this way shows that there is no inherent “progress” to evolution as a whole, only local adaptations, the true definition of “natural selection”.