Researchers often pursue proof of concept research, but criteria for evaluating such research remain poorly specified. This paper proposes a general framework for proof of concept research that knits together and augments earlier discussions. The framework includes prototypes, proof of concept demonstrations, and post facto demonstrations. With a case from theoretical evolutionary genetics, the paper illustrates the general framework and articulates some of the reasoning strategies used within that field. This paper provides both specific tools with which to understand how (...) researchers evaluate models in theoretical evolutionary genetics, and general tools that apply to proof of concept research more generally. (shrink)

Clade selection is unpopular with philosophers who otherwise accept multilevel selection theory. Clades cannot reproduce, and reproduction is widely thought necessary for evolution by natural selection, especially of complex adaptations. Using microbial evolutionary processes as heuristics, I argue contrariwise, that (1) clade growth (proliferation of contained species) substitutes for clade reproduction in the evolution of complex adaptation, (2) clade-level properties favoring persistence – species richness, dispersal, divergence, and possibly intraclade cooperation – are not collapsible into species-level traits, (3) such properties (...) can be maintained by selection on clades, and (4) clade selection extends the explanatory power of the theory of evolution. (shrink)

William Keith Brooks was an American zoologist at Johns Hopkins University from 1876 until his death in 1908. Over the course of his career, Brooks staunchly defended Darwinism, arguing for the centrality of natural selection in evolutionary theory at a time when alternative theories, such as neo-Lamarckism, grew prominent in American biology. In his book The Law of Heredity, Brooks addressed problems raised by Darwin’s theory of pangenesis. In modifying and developing Darwin’s pangenesis, Brooks proposed a new theory of heredity (...) that sought to avoid the pitfalls of Darwin’s hypothesis. In so doing he strengthened Darwin’s theory of natural selection by undermining arguments for the inheritance of acquired characteristics. In later attacks on neo-Lamarckism, Brooks consistently defended Darwin’s theory of natural selection on logical grounds, continued to challenge the idea of the inheritance of acquired characteristics, and argued that natural selection best explained a wide range of adaptations. Finally, he critiqued Galton’s statistical view of heredity and argued that Galton had resurrected an outmoded typological concept of species, one which Darwin and other naturalists had shown to be incorrect. Brooks’s ideas resemble the “biological species concept” of the twentieth century, as developed by evolutionary biologist Ernst Mayr and others. The late-nineteenth century was not a period of total “eclipse” of Darwinism, as biologists and historians have hitherto seen it. Although the “Modern Synthesis” refers to the reconciliation of post-Mendelian genetics with evolution by natural selection, we might adjust our understanding of how the synthesis developed by seeing it as the culmination of a longer discussion that extends back to the late-nineteenth century. (shrink)

The discussion with Rao and Nanjundiah about the history of interactions between J. B. S. Haldane and Ernst Mayr is further extended in this note. The nature of the dispute about beanbag genetics is explicated as consisting of two separate issues, one about the role of mathematical analysis in evolutionary biology, and the other about the value of single-locus genic models.

Ernst Mayr and J. B. S. Haldane, major contributors to the ‘modern synthesis’ in evolutionary theory, set an example of how scientific disagreements need not come in the way of friendship. After getting acquainted, they kept discussing issues related to evolution until just before Haldane’s death in 1964. Their dissimilar backgrounds meant that they adopted different approaches. A major disagreement emerged regarding the right way to look at the role of genes in evolution. Mayr felt that the elementary models of (...) population genetics were oversimplifications and therefore inadequate for representing evolutionary processes, though he was not consistent in his attitude. Haldane, on the other hand, maintained that the mathematical treatment of simple models had an important role to play. The Mayr-Haldane interactions illustrate divergent viewpoints concerning the utility of mathematics in biology. (shrink)

Different types of explanations coexist in present-day biology. Functional explanations describe mechanisms, whereas evolutionary explanations provide answers to the question “why?” mostly by appealing to the past and present action of natural selection. But the relations between these two types of explanations, as well as the relative insights they offer, vary from one domain of research to another. We will illustrate this complex landscape of biological explanations with three examples involving aging, the sex ratio, and the phenomenon of genomic imprinting. (...) We will show that the two types of explanations have recently often progressed towards each other. In consequence, they cease to be “pure” functional or evolutionary explanations and become explanations that may be alternatively considered as functional or evolutionary. (shrink)

One of the major benefits of interdisciplinary research is the chance to swap tools between fields, to save having to reinvent the wheel. The fields of language evolution and evolutionary biology have been swapping tools for centuries to the enrichment of both. Here I will discuss three categories of tool swapping: conceptual tools, where analogies are drawn between hypotheses, patterns or processes, so that one field can take advantage of the path cut through the intellectual jungle by the other; theoretical (...) tools, where the machinery developed to process the data in one field is adapted to be applied to the data of the other; and analytical tools, where common problems encountered in both fields can be solved using useful tricks developed by one or the other. I will argue that conceptual tools borrowed from linguistics contributed to the Darwinian revolution in biology; that theoretical tools of evolutionary change can in some cases be applied to both genetic and linguistic data without having to assume the underlying evolutionary processes are exactly the same; and that there are practical problems that have long been recognised in historical linguistics that may be solved by borrowing some useful analytical tools from evolutionary biology. (shrink)