Human evolution theory utilizing concepts of neoteny & female sexual selection
An etiology of neuropsychological disorders such as autism and dyslexia, and the origin of left handedness.
Far from being the first evolutionary theory with a wide spread across several disciplines, we will here briefly address evidence of other multi-disciplinary evolution theories. The modern synthesis represents just that, a convergence of the work of several disciplines. Shift theory increases the breadth of that synthesis by bringing into its revised structure the work of anthropologists, neuroscientists and medical clinicians.
This chapter also seeks to make clear the relationship between the different selective processes introduced in the last chapter. We hypothesize that natural selection created sexual selection, uterine selection and zygote selection. In this context we can agree with the sociobiologists that natural selection is the bottom line driving force behind evolution, though we still have a problem with variation being random (see Perceptual Presuppositions).
Last, we revisit the works of Charles Darwin in light of the conclusions we've reached since last we looked at his works in chapter 3. We believe that Darwin in his 6th and last edition of The Origin of Species, was still struggling for his own synthesis. This later work does not represent a capitulation to his opponents as is suggested by many neo-Darwinists today. With today's data, studies, and theoretical tools, we believe Darwin would be barrelling down the same path we are following.
Between 1808 and 1814 Tiedermann published a series of papers tying together what he perceived as evidence that embryological development and species relationships were closely aligned (Richards, 1992). Agissiz made the conceptual leap that brought in the fossil record to correspond to the patterns evident in living species and the embryological record (Gould, 1977).
"To Agassiz, the threefold parallelism reflected the unity of God's plan for His creation. It was also a fact of observation. What more need a Cuvierian empiricist say? "The leading thought which runs through the succession of all organized being in past ages is manifested again in new combinations, in the phases of the development of the living representatives of those different types. It exhibits everywhere the working of the same creative Mind, through all times, and upon the whole surface of the globe" (1857, p, 115) Agassiz invoked his God specifically to forestall any evolutionary reading of recapitulation: .... Yet, Agassiz's view contained an argument that no evolutionist could resist interpreting. If the fossil record is only a temporal display of the same divine plan that animals reflect in their own ontogeny, then the geologic component of Agassiz's threefold parallelism merely extends the scope of recapitulation and the generality of benevolent design. But if fossils record an actual history of physical descent, then the argument must be inverted. The geologic record is no mere addition to a twofold parallelism between embryonic stages and the structural gradation of living forms; it is the fundamental sequence that engenders the other two. The structural gradation of living forms is merely its artifact, because primitive animals have survived in each type. Embryonic stages are only its reflection, because an embryo must repeat the shapes of its ancestors before adding its own distinguishing features. Agassiz's parallelism, a divine union of three independent sequences, becomes the mechanical result of a single causal chain leading from the geologic record to the stages of embryology: ontogeny recapitulates phylogeny." (Gould, S.J. (1977) Ontegeny and Phylogeny. Cambridge: Belknap Press. p. 67-8)
Agissiz, a firm creationist, opened the floodgates that recapitulationists poured through. For sixty years, patterns in a number of disciplines were interpreted from the theoretical belief that not only did ontogeny recapitulate phylogeny, but that the fossil record reflected this truth. Frazer, a founder of comparative mythology, viewed 'primitive' humans as the evolutionary equivalent of western children (Bowler, 1988). Associating the 'savage' and the child became conventional wisdom with turn-of-the-century educational philosophy reflecting this belief (Gould, 1977).
In 1887, Lombroso (Gould, 1977) used this three-fold pattern to explain the origin and exhibition of criminal characteristics in contemporary populations. He believed that many criminals were atavisms or throw-backs that acted out the savage tendencies of aboriginal contemporary cultures, or the behavior of modern western children.
Taking the recapitulatory pattern even further, using it to explain the origin of mental illness and even the order of illnesses in relation to their evolutionary sequence, Freud believed that mental illness had an evolutionary foundation.
"Freud once even argued that differences among mental abnormalities might reflect the different ancestral stages (=periods of childhood) at which libido became fixed. We should be able to arrange the neuroses themselves in phyletic order. In 1915, he wrote to Ferenczi: "Anxiety hysteria--conversion hysteria--obsessional neurosis--dementia praecox--paranoia--melancholia--mania...This series seems to repeat phylogenetically an historical origin. What are now neuroses were once phases in human conditions" (in McCormick, 1973, p. 17). Indeed, Freud did not shrink from completing the recapitulatory system of his beliefs. In the extraordinary closing words of his report on the Schreber case, Freud rediscovers the fourfold parallelism of classical recapitulation: the child, the modern savage, our primitive ancestor, and the adult neurotic all represent the same phyletic stage--the primitive as true ancestor, the savage as modern survivor, the child as a recapitulated adult ancestor in Haeckelian terms, and the neurotic as a fixated child (=primitive): "I am of the opinion that the time will soon be ripe for us to make an extension of a principle of which the truth has long been recognized by psychoanalysts, and to complete what has hitherto had only an individual and ontogenic application by the addition of its anthropological and phylogenetically conceived counterpart. 'In dreams and neuroses,' so our principle has run, 'we come once more upon the child and the peculiarities which characterize his modes of thought and his emotional life.' 'And we come upon the savage too," thus we may complete our proposition, "upon the primitive man, as he stands revealed to us in the light of the researches of archaeology and of ethnology." (1911, in 1963, p. 186, italic original)" (Gould, S.J. (1977) Ontegeny and Phylogeny. Cambridge: Belknap Press. p. 158-9)
Gould (1977) quotes Piaget. "Unfortunately, we are not very well informed in the psychology of primitive man, but there are children all around us, and it is in studying children that we have the best chance of studying the development of logical knowledge, mathematical knowledge, physical knowledge, and so forth." Many modern theorists across many disciplines retain an evolutionary explanation for the their specialty. Bickerton (1981) in his Roots of Language explores a possible evolutionary explanation for the origin of language. In Roots he equates the original evolution of language in humans with both the origin of new languages such as pidgins and creoles and the development of language use abilities in individual humans.
It is the premise of this work that non-recapitulatory multi-disciplinary evolutionary explanations are not just possible, but useful. The modern synthesis represents such a case. Shift theory and transitional model 1.0 has precedents as it seeks to bring into the modern synthesis an evolutionary explanation for culture creation while at the same time generating a model that describes an evolutionary etiology for neurological disorders, certain cancers, and several of the mental maladies Freud referred to using his recapitulatory explanations.
This work professes to offer a unified theory of biological and cultural evolution bringing together formerly unrelated disciplines. Previous attempts were mired in cultural biases that presuppositionally put western culture at the top of any such evolutionary scheme. Recapitulatory theories reflected these prejudices. Shift theory begins again using a different scheme, unburdened by recapitulation and social Darwinism. For example, in section IV, when we discuss the effects of the drop of 3 1/2 to 4 years in pubertal onset in worldwide urban culture (the heterochronic process called progenesis) we will see that this last stage of development leaves us looking at aboriginal cultures with a profound sense of loss. The earlier timing of pubertal onset, caused by a naturally selected reflex to increase procreation rates in the event of a long term dietary bonanza (Gould, 1977), has cut off the lion's share of the final stage of cerebral development, abstract thinking. If it seems like we don't think/feel as clearly as our aboriginal brethren, it is because we don't.
Darwin specified in his theory of natural selection that variation is random. This is, perhaps, the most theoretically conflicted element of Darwin's works. Both in his The Origin of Species, 6th ed. and in his The Variation of Animals and Plants Under Domestication, Darwin makes clear that he believes that variation is not random, that both use and disuse and environmental influences such as climate compel the creation of progeny preselected for an environment. Darwin's inability to form a synthesis of natural selection, sexual selection, and progenesis revolves around this issue of whether variation is random, not random, or something in between.
Researchers from Mivart to Steele have focussed on the fulcrum that random variation represents. Darwin was frustrated by his own efforts at the reconciliation of the two extremes represented by natural selection and progenesis. It is our belief that the problem has been one of logical levels, a common source of confusion as pointed out by Gregory Bateson in his discussions of Whitehead's theory of logical types. Natural selection is not on the same logical level as sexual selection or progenesis; described as sexual selection, uterine selection and zygote selection in our model. Natural selection is the progenitor, the ancestor of the other selective processes. Natural selection selected for sexual selection, uterine selection, and zygote selection. None of the products of the other three selective processes can meet the requirements of evolution unless they also pass the test of natural selection, that they survive to procreation age and procreate.
Cultural selection is one additional selective process not yet alluded to in this work. Cultural selection, learning on an abstract level, is a product of female sexual selection. It lies two levels down from natural selection, but still must past muster when it comes down to an individual's survival to procreation age. Ideas also die, and must compete for survival like a fashionable color or song in female sexual selection. How exactly culture is a product of female sexual selection will be explored in section II and III.
So, just as there is a branching tree of species representing their relationships over time, there is a smaller branching tree of selective processes representing their relationships and how one selective process generates another. With each branching there is a more select group of species effected by the processes at issue. Natural selection affects all. Sexual selection, uterine selection and zygote selection affect many. Cultural selection affects very few, and only one species we are aware of uses an abstract language.
What drives this dynamic is the immediate advantage any individual has if he or she can transcend the barrier that is random variation. Any feasible feature that an individual can generate, preadapted for the environment he or she (or his or her progeny) will be born into, is a huge advantage over an individual without a preadapted feature. This is what it is all about. Whatever the individual is competing for: more sunlight, prey, speed, smaller or greater size; if that individual can discern which direction will give it an advantage, it's progeny, when they inherit that ability, will be more likely to survive to procreate.
Stephen J. Gould (1993) surmises that sexual selection may have been naturally selected as an effective tool for finding a mate genetically distant enough to avoid the dangers of inbreeding but genetically close enough to avoid an individual selected for an environment too different from the one the successful chooser has survived. Altruism theorists Hamilton, (1964) and Trivers (1971) also hypothesize that there are benefits conferred upon individuals choosing mates genetically close by, but not too close by. Dawkins (1976) describes the costs of mating too far (sterility) or too close (incest leading to unuseful recessive gene manifestation). Gould cites P. Bateson's (1982) work with quails to support his suppositions.
"The implications of these findings is that an individual is able to strike an optimal balance between inbreeding and outbreeding by learning about its immediate kin and mating with a member of the opposite sex that is slightly different from its immediate kin. What such a balance might amount to in practice has previously been uncertain. I report here that Japanese quail of both sexes, having been reared with their siblings, subsequently prefer a first cousin of the opposite sex. ( Bateson, P. (1982) Preferences for cousins in Japanese quail Nature 295: p. 236)
In the study cited by Bateson, the quails are choosing between a sibling they are familiar with, a sibling they have never met, a first cousin they have never met, a third cousin they have never met, and a non related stranger they have never met. The female bird chooses a first cousin; an individual close enough that they will share the genes that have succeeded in the local environment but far enough apart that there is some variation in progeny to weather environmental fluctuations. Sexual selection gives a female an advantage over other females of her species not engaged in this sorting process. And, referring back to Fisher (1930), the runaway process of sexual selection confers upon the successful participants even greater advantages when complying with fashionable looks or sounds.
The evolutionary selective processes themselves, have evolved. Human being represent a very subtle combination of all the selective processes. By exploring and understanding the nature of the relationships between those selective processes over the last several hundred thousand years of human evolution, we can tease out the dynamic responsible for the origin of our species. The bonus of this alternative approach is a dynamic understanding of how culture was created, how culture evolves, and the origin and structure of a number of diseases and conditions, etiologies presently unknown.