According to sources both in print and at a recent meeting, evolutionary theory is currently undergoing change which some would characterize as a New Synthesis, and others as an Extended Synthesis. This article argues that the important changes involve recognizing that there are three means by which evolutionary change can be initiated and three corresponding modes of evolutionary drift. It compares the three and goes on to discuss the scale of innovation and extended or inclusive and Lamarckian inheritance. It concludes (...) from these that “new trends in evolutionary biology” are in part a new, and in part an extended evolutionary synthesis. (shrink)

Abstract A lot of science has passed under the bridge since the classic definition of evolution as a change in gene frequencies in a population became common. Much knowledge has accumulated since then about evolution, heredity, ecology, development, phenotypic plasticity, niche construction and genetic drift. Building on Van Valen’s description of evolution as “the control of development by ecology,” it is suggested that the classic definition be replaced by a updated ‘eco‐evo-evo’ definition of evolution by natural selection which acknowledges this (...) accumulation. (shrink)

If all origins of life or of any new grade, level, or major transition as such begin with “competitive development”—with juveniles rather than adults, and multiple individuals rather than a single one—then the evolution of progeneration and of replication always requires an explanation. This article proposes that principles of evolutionary ecology such as density-dependence can be used to explain three kinds of developmental repetitions, viz., sequences of inductive and niche-constructing interactions between the ecological environment and population members, which take place (...) in such a way that the sequence is repeated: individual or somatic repetitions, discussed in Section 1, demographic or progenerative repetitions , discussed in Section 2, and replicative repetitions , discussed in Section 3. This results in a statement of the evolutionary process that includes rather than excludes development and ecology, but one which requires some additions to Van Valen’s aphorism that evolution is the control of development by ecology. (shrink)

This article utilizes three premises. There are commonly ecologically oriented, naturally selected specialized differences in frequency and/or quality as well as sexually selected differences between the sexes. Sex in the sense of coming together and going apart or going apart and coming together is trade in these naturally selected differences, i.e., there is a mating market in sexual species. While such trade is beneficial to the population as a whole, sexual competition and selection is conflict over the profits of that (...) trade and can be detrimental to the population as a whole. These premises yield a naturally selected sex allocation theory of the possible directions and forms of sexual selection, i.e., one that includes costs as well as frequencies. This can explain conventional sex roles, the sex-role reversed, inter- as well as intrasexual selection, and passive as well as active choice. Any of these alternatives may be over mates, over gametes, or both. A hypothetical example based on density dependence relative to resources is provided, one that suggests that centrioles may be a cytoplasmic resource in males in multicellular animals, and which are the target of active choice and the mechanism of manipulation in passive female choice. As a whole, the approach yields a truly general theory of sexual selection, provides an alternative to the mechanism for Fisher’s principle, and gives a theoretical explanation for Mayr’s biological species definition. (shrink)

This research was inspired by Werner Callebaut's (1993) classic in which he interviewed major contemporary philosophers of science (specifically of biology) at a time when the interdisciplinary label of "science studies" had hardly been invented. The "real" in his title, Taking the Naturalistic Turn: How Real Philosophy of Science is Done, was a playful reference to debates over realism in Philosophy—the title as a whole drawing attention to his intent to study science studies empirically. That, for Callebaut, was "real" philosophy.In (...) the research reported on here, the works of ten major theorists of the scientific/scholarly process were studied (but not exclusively of biology and chosen from a larger set which .. (shrink)

Four theoretical monographs, written by biologists in the wake of the sociobiology debate, and which treat, or purport to treat, the topic of sociocultural evolution are examined in this paper. On the biosocial spectrum they range from Trivers' pure sociobiology, to Lumsden and Wilson's sociobiology "in drag," to Boyd and Richerson's genuinely dual approach, to Cavalli-Sforza and Feldman's purely cultural transmission and evolution. The latter is likely to prove of greatest interest to social scientists and represents a major advance in (...) theorizing mathematically about social change. While the most comprehensive, Boyd and Richerson's "dual inheritance" model ultimately places more emphasis on the biological evolution of the capacity for culture than on genuine gene/culture coevolution even though it is conceivable that cultural transmission and evolution could be providing the selective force responsible for some fundamental biological phenomena such as sexual reproduction in long-lived vertebrates for example. The relationship between contemporary evolutionary and non-evolutionary theories of social change is not dealt with here but the former are very relevant to the latter because evolutionists believe they have available sophisticated solutions to problems which continue to plague other theoretical traditions. (shrink)

Despite a revived interest in explaining the evolution of anisogamy in recent years (i.e. different—micro and macrogametes), there remain more questions than answers. The topic is important because it is thought to be the foundation of the theory of gender differences and relations. Twelve of these questions are briefly reviewed here—(1) the distinction between sex and sexual types; (2) the distinction between mating types and anisogamy; (3) the possible role of ecological as well as social evolution in proto-gender differences and (...) relations; (4) the life history strategies involved; (5) whether the relevant social relationships are based on conflict or cooperation; (6) the origin and properties of meiosis; (7) the conformity of theories with sex allocation theory; (8) the relevance of multiple levels of selection; (9) appropriate modelling strategies; (10) the relationship between the kind of gametes produced and secondary sexual characteristics; (11) the relevance to humans; and (12) how realistic the search for a single explanation is. It is concluded that polarized sexuality may be a form of trade. (shrink)

This note provides a definition of evolution by natural selection that is compatible with the extended evolutionary synthesis.

Many analogies exist between the process of evolution by natural selection and of learning by reinforcement and punishment. A full extension of the evolutionary analogy to learning to include analogues of the fitness, genotype, development, environmental influences, and phenotype concepts makes possible a single theory of the learning process able to encompass all of the elementary procedures known to yield learning.

A lesson in evolutionary theory can be drawn from the work of Rick Charnov, who transformed Fisher’s sex ratio theory into sex allocation theory, but unfortunately, the lesson has not spread far enough. The lesson is that costs as well as frequencies need to be included. That is so whether we are talking about evolutionary ecology (e.g., density dependence), social evolution (e.g., sexual selection), origins, an extended evolutionary synthesis, multilevel selection, or whatever. The two dimensions can be expressed in a (...) variety of ways—investing as well as spending, quality as well as quantity, costs as well as frequencies, and somatic as well as reproductive functions, for example. Both are needed everywhere in evolutionary theory. (shrink)

Evolutionary socioecological theory and research proposing linking parasites with human social organization is uncommon and therefore welcome. However, more generally, condition-dependent adaptive phenotypic plasticity requires environmental uncertainty on a small scale, accompanied by reliable cues. In addition, genes in parasites may select among biologically adaptive cultural alternatives directly without necessarily going through human genetic predispositions, resulting in inter-specific gene-culture coevolution.

The most general theory of life history evolution, that of r versus K selection, implies that innovation in the form of plasticity is more likely to be adaptive under poor rather than good resource conditions, the opposite of how Baumard has it. However, this does focus on benefits rather than costs, and including both allows for greater diversity of outcomes.

Social learning in the strict sense is learning by observation or instruction. Learning by observation appears to be an analogue process while learning by instruction is digital. In evolutionary biology this distinction is currently thought to have implications for the extent to which mechanisms can function successfully as an inheritance system in an evolutionary process.

This short paper is about the generalized evolutionary approach to the economics of science. Stephen Toulmin and David Hull are pioneers of the former rather than Karl Popper whose falsification thesis was sociologically naive. Useful directions for the future would go beyond the generalities of variation, transmission and selection towards making more explicit use of Darwin’s “two great principles.” The first is “the unity of types” i.e. common descent by employing phylogenetic methods to answer historical questions. The second is “the (...) conditions of existence” i.e. natural selection by making use of general principles of evolutionary ecology and socioecology to answer questions about why something evolved. (shrink)

On September 30th I attended a talk by Ian Hacking, the renowned philosopher of science. The topic, “The Tree of Knowledge,” was irresistible for someone like myself whose main interest is in sociocultural evolution. I was rewarded with a dazzling display of erudition about stylized trees drawn through history and across civilizations. Hacking generously credited the many experts he had consulted to amass this treasure. This was consistent with his preference for “collaborating disciplines” over interdisciplinarity.