We trace the history of the Modern Evolutionary Synthesis, and of genetic Darwinism generally, with a view to showing why, even in its current versions, it can no longer serve as a general framework for evolutionary theory. The main reason is empirical. Genetical Darwinism cannot accommodate the role of development (and of genes in development) in many evolutionary processes. We go on to discuss two conceptual issues: whether natural selection can be the “creative factor” in a new, more general framework (...) for evolutionary theorizing; and whether in such a framework organisms must be conceived as self-organizing systems embedded in self-organizing ecological systems. (shrink)

I reconstruct the relationship between the evolutionary geneticists Theodosius Dobzhansky (1900–1975) and Richard Lewontin (1929–2021). Using archival research and published texts, I show that Lewontin inherited his dissertation director’s research program as well as his “biology of democracy.” He did so in circumstances in which the molecular revolution in genetics was threatening both Dobzhansky’s science and his anti-racist social ideals. Lewontin’s sometimes rocky relationship with the person he called “my professor” sprang from his perception that Dobzhansky was not up to (...) managing the research program that Lewontin received from him. I explain how Lewontin took charge and the role his Marxist interpretive lens plays in his argument. (shrink)

John Reiss is a practicing evolutionary biologist (herpetology) who by his own account happened to be in the right place (Harvard’s Museum of Comparative Zoology) at the right time (the 1980s) to hear echoes of the debate about sociobiology that had been raging there between E. O. Wilson and, on the other side, Stephen Jay Gould and Richard Lewontin (xiv). Reiss is not concerned with sociobiology, at least in this book, but with the adaptationism that Gould and Lewontin saw in (...) the sociobiologists’ approach to cooperative behavior. At Harvard, Reiss was guided by Pere Alberch, in whose laboratory Gould’s stress on developmental constraints was being transformed into a now influential version of the Evo-devo movement (xiv, 327). On Alberch’s view, which Reiss accepts, variation in the rate, timing, placement, and intensity of gene products during the ontogenetic process, rather than mutation in structural genes, constitutes the proximate source of the phenotypic variation on which natural election works (327-29). Reiss does not think that Evo-devo, at least as he construes it, does away with natural selection. Rather, he seeks to identify the role played by selection in retaining or eliminating the variation generated in the developmental process. Selection, he argues, enables organisms, populations, species, and other lineages to maintain the presumptively adapted conditions of existence to which their very persistence already testifies. “Adaptedness,” Reiss writes, “is not a product of evolution; it is a condition for evolution” (22). He thinks that this fact, as he takes it to be, belies the adaptationist assumption that organisms are collections of independently optimal adaptations that arise by way of concerted spurts of directional selection. “It is a mistake,” he writes, “to atomize organisms and to explain each part as the solution of a problem raised by the environment” (295). (shrink)

Using the evolution of the stickleback family of subarctic fish as a touchstone, we explore the effect of new discoveries about regulatory genetics, developmental plasticity, and epigenetic inheritance on the conceptual foundations of the Modern Evolutionary Synthesis. Identifying the creativity of natural selection as the hallmark of the Modern Synthesis, we show that since its inception its adherents have pursued a variety of research projects that at first seemed to conflict with its principles, but were accommodated. We situate challenges coming (...) from developmental biology in a dialectic between innovation and tradition, suggesting on the basis of past episodes that even if developmental plasticity and epigenetic inheritance are aligned with its principles the Modern Synthesis will be significantly affected. (shrink)

Ecology in principle is tied to evolution, since communities and ecosystems result from evolution and ecological conditions determine fitness values. Yet the two disciplines of evolution and ecology were not unified in the twentieth-century. The architects of the Modern Synthesis, and especially Julian Huxley, constantly pushed for such integration, but the major ideas of the Synthesis—namely, the privileged role of selection and the key role of gene frequencies in evolution—did not directly or immediately translate into ecological science. In this paper (...) I consider five stages through which the Synthesis was integrated into ecology and distinguish between various ways in which a possible integration was gained. I start with Elton’s animal ecology, then consider successively Ford’s ecological genetics in the 1940s, the major textbook Principles of animal ecology edited by Allee et al., and the debates over the role of competition in population regulation in the 1950s, ending with Hutchinson’s niche concept and McArthur and Wilson’s Principles of Island Biogeography viewed as a formal transposition of Modern Synthesis explanatory schemes. I will emphasize the key role of founders of the Synthesis at each stage of this very nonlinear history. (shrink)

This paper questions the form and prospects of “extended theories” which have been simultaneously and independently advocated both in the philosophy of mind and in the philosophy of biology. It focuses on Extend Mind Theory (EMT) and Developmental Systems Theory (DST). It shows first that the two theories vindicate a parallel extension of received views, the former concerning extending cognition beyond the brain, the latter concerned with extending evolution and development beyond the genes. It also shows that both arguments rely (...) on the demonstration of causal parities, which have been undermined by the classical received view. Then I question whether the argument that there is an illegitimate inference from parities or coupling to constitution claims, which has been objected by Adams and Aizawa in The bounds of cognition, (2008) to EMT, also holds against DST. To this aim, I consider two defenses against DST that are parallel to two defenses against EMT, one about intrinsic content, the other about the difference between what’s in principle possible and what happens in practice. I conclude by claiming that the weaknesses and strengths of both theories are different regarding these two kinds of objections. (shrink)

In this paper, we analyze the debate between the Modern Synthesis and the Extended Evolutionary Synthesis in light of the concept of incommensurability developed by Thomas Kuhn. In order to do so, first we briefly present both the Modern Synthesis and the Extended Evolutionary Synthesis. Then, we clarify the meaning and interpretations of incommensurability throughout Kuhn’s works, concluding that the version of this concept deployed in The Structure of Scientific Revolutions is the best suited to the analysis of scientific disputes. (...) After discussing incommensurability in Kuhn’s works, we address the question of whether the Modern Synthesis and the Extended Evolutionary Synthesis can be considered semantically, methodologically, and ontologically incommensurable, concluding that they can. Finally, we discuss three problems that arise from such a conclusion: firstly, what are the consequences of incommensurability; secondly, which mode of scientific change better explains this current dispute in evolutionary biology; and thirdly, whether rational theory comparison is possible given incommensurability. We suggest that the main consequence of incommensurability is profound disagreement, that the kind of scientific change that better explains the current dispute between the MS and the EES may be scientific specialization, and that incommensurability does not preclude rational theory comparison. (shrink)

This paper surveys questions about the nature of the Modern Synthesis as a historical event : was it rather theoretical than institutional? When and where did it actually happen? Who was involved? It argues that all answers to these questions are interrelated, and that systematic sets of answers define specific perspectives on the Modern Synthesis that are all complementary.

A number of areas of biology raise questions about what is of value in the natural environment and how we ought to behave towards it: conservation biology, environmental science, and ecology, to name a few. Based on my experience teaching students from these and similar majors, I argue that the field of environmental ethics has much to teach these students. They come to me with pent-up questions and a feeling that more is needed to fully engage in their subjects, and (...) I believe some exposure to environmental ethics can help focus their interests and goals. I identify three primary areas in which environmental ethics can con- tribute to their education. The first is an examination of who (or what) should be considered to be part of our moral community (i.e., the community to whom we owe direct duties). Is it humans only? Or does it include all sentient life? Or all life? Or ecosystems considered holistically? Often, readings implicitly assume one or more of these answers; the goal is to make the student more sensitive to these implicit claims and to get them to think about the different reasons that support them. The second area, related to the first, is the application of the different answers concerning the extent of the ethical community to real environmental issues and problems. Students need to be aware of how the different answers concerning the moral community can imply conflicting answers for how we should act in certain cases and to think about ways to move toward conflict resolution. The third area in which environmental ethics can contribute is a more conceptual one, focusing on central concepts such as biodiversity, sustainability, species, and ecosystems. Exploring and evaluating various meanings of these terms will make students more reflective and thoughtful citizens and biologists, sensitive to the implications that different conceptual choices make. (shrink)