In recent years evolutionary theorists have been engaged in a protracted and bitter disagreement concerning how natural selection affects units such as genes, individuals, kin groups, and groups. Central to this debate has been whether selective pressures affecting group success can trump the selective pressures that confer advantage at the individual level. In short, there has been a debate about the utility of group selection, with noted theorist Steven Pinker calling the concept useless for the social sciences. We surveyed 175 (...) evolutionary anthropologists to ascertain where they stood in the debate. We found that most were receptive to group selection, especially in the case of cultural group selection. The survey also revealed that liberals and conservatives, and males and females, all displayed significant differences of opinion concerning which selective forces were important in humanity’s prehistory. We conclude by interpreting these findings in the context of recent research in political psychology. (shrink)

It is clear from the above discussion that if I had wished to do so I could have truthfully presented every paper as either testing a prediction, presenting evidence needed in the test of a prediction, or presentin a D-N explanation. (I would not have been able to do this if I had not been sufficiently familiar with the evolutionary literature to recognize what hypotheses were at stake in several of the papers; even when the authors mention the hypotheses they (...) frequently do so only in enough detail to put their paper in context for the knowledgeable biologist.) Since these biologists are working in a period of normal science under the paradigm of the modern synthetic theory of evolution, none of these papers is presented as a test of the modern synthetic theory; but since this theory was used in the derivation of each prediction, each one is a test of it as well as of the hypothesis mentioned. Thus, once we learn to recognize the predictions beneath their cloaks of invisibility, we discover that prediction testing is not, as philosophers have claimed, at best peripheral to evolutionary biology; it is central to evolutionary biology. (shrink)

Genes are thought to have evolved from long-lived and multiply-interactive molecules in the early stages of the origins of life. However, at that stage there were no replicators, and the distinction between interactors and replicators did not yet apply. Nevertheless, the process of evolution that proceeded from initial autocatalytic hypercycles to full organisms was a Darwinian process of selection of favourable variants. We distinguish therefore between Neo-Darwinian evolution and the related Weismannian and Central Dogma divisions, on the one hand, and (...) the more generic category of Darwinian evolution on the other. We argue that Hull’s and Dawkins’ replicator/interactor distinction of entities is a sufficient, but not necessary, condition for Darwinian evolution to take place. We conceive the origin of genes as a separation between different types of molecules in a thermodynamic state space, and employ a notion of reproducers. (shrink)

This paper shows that species are individuals with respect to evolutionary theory in the sense that the laws of the theory deal with species as irreducible wholes rather than as sets of organisms. 'Species X' is an instantiation of a primitive term of the theory. I present a sketch of a proof that it cannot be defined within the theory as a set of organisms; the proof relies not on details of my axiomatization but rather on a generally accepted property (...) of speciation; hence the same argument should work for any axiomatization which captures this generally accepted property of speciation. (shrink)

Explaining the persistence of populations is an important quest in ecology, and is a modern manifestation of the balance of nature metaphor. Increasingly, however, ecologists see populations (and ecological systems generally) as not being in equilibrium or balance. The portrayal of ecological systems as “non-equilibrium” is seen as a strong alternative to deterministic or equilibrium ecology, but this approach fails to provide much theoretical or practical guidance, and warrants formalisation at a more fundamental level. This is available in adaptation theory, (...) which allows population persistence to be explained as an epiphenomenon stemming from the maintenance, survival, movement and reproduction of individual organisms. These processes take place within a physicochemical and biotic environment that persists through structured annual cycles, but which is also spatiotemporally dynamic and subject to stochastic variation. The focus is thus shifted from the overproduction of offspring and the consequent density dependent population pressure thought to follow, to the adaptations and ecological circumstances that support those relatively few individuals that do survive. (shrink)

The fundamental postulate of sociobiology is that individuals exploit favorable environments to increase their genetic representation in the next generation. The data on fertility differentials among contemporary humans are not cotvietent with this postulate. Given the importance ofHomo sapiensas an animal species in the natural world today, these data constitute particularly challenging and interesting problem for both human sociobiology and sociobiology as a whole.The first part of this paper reviews the evidence showing an inverse relationship between reproductive fitness and “endowment” (...) in contemporary, urbanized societies. It is shown that a positive relationship is observed only for those cohorts who bore their children during a unique period of rising fertility, 1935–1960, and that these cohorts are most often cited by sociobiologists as supporting the central postulate of sociobiology. Cohorts preceding and following these show the characteristic inverse relationship between endowment and fertility. The second section reviews the existing so-ciobiological models of this inverse relationship, namely, those of Barkow, Burley, and Irons, as well as more informal responses among sociobiologists to the persistent violation of sociobiology's central postulate, such as those of Alexander and Dawkins. The third section asks whether the goals of sociobiology, given the violation of its fundamental postulate by contemporary human societies, might not be better thought of as applied rather than descriptive, with respect to these societies. A proper answer to this question begins with the measurement of the pace and direction of natural selection within modern human populations, as compared to other sources of change. The vast preponderance of the shifts in human trait distributions, including the IQ distribution, appears to be due to environmental rather than genetic change. However, there remains the question of just how elastic these distributions are in the absence of reinforcing genetic change. (shrink)

One of the central tenets of Christian theology is the denial of self for the benefit of another. However, many views on the evolution of altruism presume that natural selection inevitably leads to a self-seeking human nature and that altruism is merely a façade to cover underlying selfish motives. I argue that human altruism is an emergent characteristic that cannot be reduced to any one particular evolutionary explanation. The evolutionary processes at work in the formation of human nature are not (...) necessarily in conflict with the possibility of altruism; rather, aspects of human nature are uniquely directed toward the care and concern of others. The relationship between altruism, human nature, and evolution can be reimagined by adopting an emergent view of the hierarchy of science and a theological worldview that emphasizes self-renunciation. The investigation of altruism necessitates an approach that analyzes several aspects of altruistic behavior at different levels in the hierarchy of sciences. This research includes the study of evolutionary adaptations, neurological systems, cognitive functions, behavioral traits, and cultural influences. No one level is able to offer a full explanation, but each piece adds a unique dimension to a much larger puzzle. (shrink)

Kant writes: If … the only aim of Nature regarding some creature possessed of reason and a will were its preservation, its well-being, in a word its happiness, then she would have come to a very bad arrangement in choosing its reason as executor of that aim. For all actions that it had to execute in this her intention, and the whole regulation of its behaviour would have been able to be prescribed to it much more precisely by instinct, and (...) that aim thereby much more certainly maintained, than ever could happen through reason …. (shrink)

Sober and Wilson have propose a cluster of arguments for the conclusion that “natural selection is unlikely to have given us purely egoistic motives” and thus that psychological altruism is true. I maintain that none of these arguments is convincing. However, the most powerful of their arguments raises deep issues about what egoists and altruists are claiming and about the assumptions they make concerning the cognitive architecture underlying human motivation.

This paper surveys recent philosophy of biology. It aims to introduce outsiders to the field to the recent literature (which is reviewed in the footnotes) and the main recent debates. I concentrate on three of these: recent critiques of the replicator/vehicle distinction and its application to the idea of the gene as the unit of section; the recent defences of group selection and the idea that standard alternatives to group selection are in fact no more than a disguised form of (...) group selection; and recent ideas on the role of selection in evolution, especially the role of selection in structuring the large-scale history of life. The paper connects philosophy of biology to some more general problems in the philosophy of science, and concludes with a few suggestions about unfinished business. (shrink)

The reception so far of Kitcher's Vaulting Ambition reminds me of the old saw about the difference between an optimist and a pessimist. Looking at the same glass of water, the former sees it as half full while the latter sees it as half empty. Some have seen Kitcher's book as a vindication of the possibility of an evolutionary science of human behavior; others have seen it as a devastating critique of the most influential efforts to date to construct such (...) a science. As in the joke about the water glass, both assessments have their point. Sociobiology is a research program, not a unified theory. What one can do is test particular hypotheses within this program and see whether they live up to reasonable standards of rigor and evidence. This is what Kitcher does, with great energy and care. (shrink)

The examples and concepts that Shoemaker cites are rather heterogeneous. Some distinctions need to be drawn. An optimality thesis involves not just an ordering of options, but a value judgment about them. So let us begin by distinguishing minimality from optimality. And the concept of minimality can play a variety of roles, among which I distinguish between extremum descriptions, statements hypothesizing an optimizing process, and methodological recommendations. Finally, I consider how the three categories relate to Shoemaker’s question that “Who is (...) optimizing: the scientist or nature?” . (shrink)

Unto Others (Sober and Wilson 1998) shows how the general principles of Multi-Level Selection (MLS) theory apply to selection at multiple levels of the biological hierarchy. It also argues for the existence of "genuine" evolutionary and psychological altruism. The authors’ views on altruism do not follow logically from principles of MLS, and their failure do disentangle these two themes undermines their otherwise excellent presentation of MLS theory. Rebuttal of the view that human nature is completely selfish depends not on the (...) prevalence of altruism but on the importance of group-advantageous traits that benefit both self and other group members without necessarily inflicting direct costs on outsiders. (shrink)