Whereupon Lewontin is criticized, and "Phyloepigenetics" is born

In "The triple helix" Lewontin seems to contradict himself a bit on the importance of genes. Consider this paragraph:

"Of course it is true that lions look different from lambs and chimps and humans because they have different genes, and a satisfactory explanation for the differences between lions, lambs, chimps and us need not involve other causal factors"
(Italics are mine)

Since Lewontin in his next breath talks quite a bit about the importance of environment and random noise in development, we are forced to wonder why they would not count as causal factors when it comes to explaining inter-species differences.

I suspect this is the result of a typically neodarwinian mistake born from the circular logic of their definition of evolution. Because "evolution is genetic change of populations", when observing a difference that is species-level (evolutionary) they get confused and think they can assume that difference to be the result of natural selection for genetic mutations (unless it is a very obviously a non-adaptive difference, in which case it is still genetic mutations, and drift rather than selection) . This argument in fact is repeatedly encountered in the discussion over whether human "intelligence genes" exist or not. "Evolutionary" psychologists (ultradarwinians) argue that the fact the human brain has evolved from smaller, less-smart brains like those of other apes implies natural selection for "intelligence genes" must have occurred in the human line, and thus that genes capable of increasing fitness through intelligence must indeed exist (The fact being that their effects are difficult to detect. Only using lots of data, statistical correlations for only very small increases in IQ scores is all that is ever detected for an alleged "intelligence gene)"

This argument, that seems so impeccable to those accustomed to thinking with a neodarwinian cap, can be exposed for the misleading definition-game it is when we stop to analize a few case-studies. The human trait of bipedism for instance. Below is the photograph of one of two "wolf girls", Amala and kamala, that were raised by wolves in India and then "rescued" into civilization in the 1920's. Extensive written and photographic documentation were produced by the priest who took care of them. As you can see in the photograph, the girls used quadrupedal, rather than bipedal, locomotion. The priest tried hard but made little progress training them into walking like people. They did not speak and and had obviously subnormal cognitive capacities for human standards .


You would think that genetic influences over general human anatomical structure would be sufficient to lead to bipedality. However, let us remember that in our ontogeny we do, in fact, learn to walk bipedally. This important difference between humans and other animals seems to not come about without an appropiate context, provided by interactions among humans, which are in fact required for preserving the behavior of bipedal walking .

Let's talk about symbolic language, another difference between humans and other species. Beyond Amala and Kamala, it is clear from numerous documented cases of feral or cruel upbringing of children, that children deprived from human interaction will not learn to speak and will develop a severely subnormal intelligence. But perhaps more interesting is the reverse experiment, that is, not only is it possible that a human may not learn to speak despite of any "language genes", but also, it is a fact that non-human primates can learn sign language and use it to communicate, despite any lack of "language genes". In this case, an important part of that species difference has been phenocopied in the other species, once again, with the aid of an adequate environmental context.

So, there definitely is an epigenetic component to the explanation of cross-species differences. A purely genetic causation could never be a satisfactory explanation. We will find that, as we compare the terminal taxa of a phylogentic tree, we will be able to see nodes in which clearly different epigenetic conditions have become established and can be directly responsible for great phenotypic differences or epigenetic apomorphies ; the sublime confirmation of everything is, of course, the experimental phenocopy or reversal through alteration of the suspect epigenetic factor.

I can think of several confirmed examples from non-human organisms and simple phenotypic traits, as well as several epigenetic hypotheses that have never been discussed before as explanations of differences between species, perhaps for lack of a more formal approach. I thus propose we begin by calling this approach Phyloepigenetics.

The intention of this post is to start several posts where we will be studying and discussing probable cases of epigenetic differences at the species-level, and thus make ourselves with a litte more "cultural baggage" to defend this new approach. I invite everyone to share examples!! I will soon be posting one about ...dinosaurs! Phyloepigenetics can be paleo, too.

Reference:
Lewontin, R. 2000 The triple Helix: Gene, Organism and Environment. Harvard University Press.