Jonathan Kaplan

Some authors defending the “hereditarian” hypothesis with respect to differences in average IQ scores between populations have argued that the sorts of environmental variation hypothesized by some researchers rejecting the hereditarian position should leave discoverable statistical traces, namely changes in the overall variance of scores or in variance–covariance matrices relating scores to other variables. In this paper, I argue that the claims regarding the discoverability of such statistical signals are broadly mistaken—there is no good reason to suspect that the hypothesized environmental causes would leave detectable traces of the sorts suggested. As there remains no way to gather evidence that would permit the direct refutation of the environmental hypotheses, and no direct evidence for the hereditarian position, it remains the case, I argue, that the hereditarian position is unsupported by current evidence

Phylogenetic information is often necessary to distinguish between evolutionary scenarios. Recently, some prominent proponents of evolutionary psychology have acknowledged this, and have claimed that such evidence has in fact been brought to bear on adaptive hypotheses involving complex human psychological traits. Were this possible, it would be a valuable source of evidence regarding hypothesized adaptive traits in humans. However, the structure of the Hominidae family makes this difficult or impossible. For many traits of interest, the closest extant relatives to the human species are too phenotypically different from humans for such methods to provide meaningful data. While phylogenetic information can be useful for testing adaptive hypotheses in humans, these generally involve traits that are (a) not widely shared in the species or (b) fairly widely shared in the Hominidae family, and hence likely of a lower order of complexity than the sorts of traits evolutionary psychology has so far been interested in.

Twenty years have passed since Gould and Lewontin published their critique of ‘the adaptationist program’ – the tendency of some evolutionary biologists to assume, rather than demonstrate, the operation of natural selection. After the ‘Spandrels paper’, evolutionists were more careful about producing just-so stories based on selection, and paid more attention to a panoply of other processes. Then came reactions against the excesses of the anti-adaptationist movement, which ranged from a complete dismissal of Gould and Lewontin’s contribution to a positive call to overcome the problems. We now have an excellent opportunity for finally affirming a more balanced and pluralistic approach to the study of evolutionary biology.

Recently, Estes and Arnold claimed to have “solved” the paradox of evolutionary stasis; they claim that stabilizing selection, and only stabilizing selection, can explain the patterns of evolutionary divergence observed over “all timescales.” While Estes and Arnold clearly think that they have identified the processes that produce evolutionary stasis, they have not. Instead, Estes and Arnold identify a particular evolutionary pattern but not the processes that produce that pattern. This mistake is important; the slippage between pattern and process is common in population and quantitative genetics and contributes to a persistent misunderstanding of the nature of explanations in evolutionary biology. †To contact the author, please write to: Philosophy Department, 208 Hovland Hall, Oregon State University, Corvallis, OR 97331‐3902; e‐mail: [email protected].

Matthen (Philos Sci 76(4):464–487, 2009) argues that explanations of evolutionary change that appeal to natural selection are statistically abstractive explanations, explanations that ignore some possible explanatory partitions that in fact impact the outcome. This recognition highlights a difficulty with making selective analyses fully rigorous. Natural selection is not about the details of what happens to any particular organism, nor, by extension, to the details of what happens in any particular population. Since selective accounts focus on tendencies, those factors that impact the actual outcomes but do not impact the tendencies must be excluded. So, in order to properly exclude the factors irrelevant to selection, the relevant factors must be identified, and physical processes, environments, and populations individuated on the basis of being relevantly similar for the purposes of selective accounts. Natural selection, on this view, becomes in part a measure of the robustness of particular kinds of outcomes given variations over some kinds of inputs

The dissertation explores the way that large-scale research projects in human genetics influence and are influenced by various social and political issues in contemporary U.S. society. In short, the dissertation argues that the same cultural assumptions which make research projects like the Human Genome Project and human behavioral genetics research seem like promising and worthwhile endeavors simultaneously lead to the results of these projects getting used to define the terms that various social issues are discussed in. In cases where the issues involve conflicting agendas, those cultural assumptions that drive the research projects often point towards a specific form of resolution, a form that is often implicitly or explicitly supported by the results of the research projects themselves. ;There is, in other words, a complex relationship of mutual support between certain kinds of research projects in human genetics, the legal and social decisions made in various areas in political life, and the kinds of discourse that can exist around those same areas. This relationship is pernicious insofar as those assumptions that encourage the research and influence the way the research is used are assumptions that many people would question the wisdom of uncritically accepting. And indeed, they are assumptions that, I argue, have strong racist and sexist overtones, assumptions born out of a radically anti-egalitarian framework. Political decisions and social discourse that might otherwise seem radically racist, sexist, or classist can, once they are being made in the shadow of research undertaken under these same kinds of assumptions, be made to seem somehow natural, inevitable, or at the very least, scientifically well-motivated

Will a synthesis of developmental and evolutionary biology require a focus on the role of nongenetic resources in evolution? Nongenetic variation may exist but be hidden because the phenotypes are stable (developmentally canalized) under certain background conditions. In this case, those differences may come to play important roles in evolution when background conditions change. If this is so, then a focus on the way that developmental resources are made reliable, and the ways in which reliability fails, may prove to be of crucial importance to linking developmental and evolutionary biology. †To contact the author, please write to: 208 Hovland Hall, Philosophy Department, Oregon State University, Corvallis, OR 97331‐3902; e‐mail: [email protected].

The concepts of adaptive/fitness landscapes and adaptive peaks are a central part of much of contemporary evolutionary biology; the concepts are introduced in introductory texts, developed in more detail in graduate-level treatments, and are used extensively in papers published in the major journals in the field. The appeal of visualizing the process of evolution in terms of the movement of populations on such landscapes is very strong; as one becomes familiar with the metaphor, one often develops the feeling that it is possible to gain deep insights into evolution by thinking about the movement of populations on landscapes consisting of adaptive valleys and peaks. But, since Wright first introduced the metaphor in 1932, the metaphor has been the subject of persistent confusion, from equivocation over just what the features of the landscape are meant to represent to how we ought to expect the landscapes to look. Recent advances—conceptual, empirical, and computational—have pointed towards the inadequacy and indeed incoherence of the landscapes as usually pictured. I argue that attempts to reform the metaphor are misguided; it is time to give up the pictorial metaphor of the landscape entirely and rely instead on the results of formal modeling, however difficult such results are to understand in ‘intuitive’ terms.

In Understanding Evolution, Kostas Kampourakis has two related goals. The first is to demonstrate that there are conceptual hurdles to properly understanding evolutionary theory. Kampourakis argues that educators, and other promoters of evolutionary theory, have underestimated how difficult it is to understand evolutionary theory and have tended to treat some gaps in understanding that are in fact the result of conceptual difficulties as if they were instead the result of, e.g., religious intolerance to the theory. This, he thinks, is a mistake. Once we accept that there are aspects of evolutionary theory that are counterintuitive, and that a host of cognitive biases make accepting evolutionary biology difficult, we will be, he argues, in a better position to present compelling argument that can work against these biases. That is the second goal of the book—to present an explanation of contemporary evolutionary theory that is attentive to the ways in which the theory might seem problem ..