Abstract: ”In the ‘generalist genes’ hypothesis, it is suggested that the same genes affect most cognitive abilities and disabilities. This recently proposed hypothesis is based on considerable multivariate genetic research showing that there is substantial genetic overlap between such broad areas of cognition as language, reading, mathematics and general cognitive ability. We assume that the hypothesis is correct and consider here its implications for cognitive neuroscience. In our opinion, the two key genetic concepts of pleiotropy (in which one gene affects many traits) and polygenicity (in which many genes affect a trait) that underlie the generalist genes hypothesis imply a ‘generalist brain’. That is, the genetic input into brain structure and function is general not specific.“ [TICS 10.5. 2006:198-203]
This does not, however preclude a domain specific and nativist theory, since these genes may just be used to manufacture recurrent features common to different domains [TICS 10.9 2006: 397-398].
It also seems that the nature-nurture debate has finally been called of, since as good as all psychological traits have genetic as well as environmental causes. Although single gene disorders exist they seem to be the exception [TICS 10.9 2006: 399-400].
Thus the mapping from one gene to many different traits under the continual interaction with the environment seems to be the emerging consensus. This minimises the role of single genes, on which mutation works. That does not necessarily falsify the central claims of EP, but I do think that it has the following consequences: 1) It is not possible to stipulate very well-formed and detailed modules for very specific purposes, but instead more general (within a specific domain) biases. 2) Much of the natural selection lies not in phylogeny, but in ontogeny and cultural history.
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Clark's book Natural Born Cyborgs makes some points relevant to the importance of ontogenesis. He notes Griffiths and Stotz article "How the Mind Grows: A Developmental Perspective on the Biology of Cognition," Synthese 122 (2000) who "argue against what they describe as the 'dualist account of human biology and human culture' according to which biological evolution must first create the 'anatomically modern human' before being followed by the long and ongoing process of cultural evolution.' ... This vision (which is perhaps not so far removed from that found in some of the more excessive versions of evolutionary psychology) is akin, they argue, to looking for the true nature of the ant by 'removing the distorting influence of the nest.'"
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