In summary, then, this discussion indicates one of the ways in which Simpson participated in the “modern evolutionary synthesis” by focusing on his developing concept of the species. In particular, we see him moving from species-as-types to species-as-populations, and next to how those populations, through organism-environment interactions, might give rise to new species, some of which rapidly lead to higher taxa.Simpson's participation in the creation of the modern synthesis is more generally evident here by his contribution to what V. B. (...) Smocovitis has recently termed the “quantification of evolution — the attachment of numbers to ‘nature.’” Smocovitis rightly views such quantification as an essential ingredient for the formulation of the evolutionary synthesis; however, she neglects Simpson's role in this regard. As suggested here and demonstrated more fully elsewhere, Simpson's commitment to a positivistic philosophy often found expression in quantitative argumentation, even if the paleontological data upon which such arguments were based were limited in number and precision. (shrink)

Ernst Mayr''s distinction between ultimate and proximate causes is justly considered a major contribution to philosophy of biology. But how did Mayr come to this philosophical distinction, and what role did it play in his earlier scientific work? I address these issues by dividing Mayr''s work into three careers or phases: 1) Mayr the naturalist/researcher, 2) Mayr the representative of and spokesman for evolutionary biology and systematics, and more recently 3) Mayr the historian and philosopher of biology. If we want (...) to understand the role of the proximate/ultimate distinction in Mayr''s more recent career as a philosopher and historian, then it helps to consider hisearlier use of the distinction, in the course of his research, and in his promotion of the professions of evolutionary biology and systematics. I believe that this approach would also shed light on some other important philosophical positions that Mayr has defended, including the distinction between essentialism: and population thinking. (shrink)

Biologists and historians often present natural history and molecular biology as distinct, perhaps conflicting, fields in biological research. Such accounts, although supported by abundant evidence, overlook important areas of overlap between these areas. Focusing upon examples drawn particularly from systematics and molecular evolution, I argue that naturalists and molecular biologists often share questions, methods, and forms of explanation. Acknowledging these interdisciplinary efforts provides a more balanced account of the development of biology during the post-World War II era.

This paper is based on my M.Sc. dissertation: ‘The Origins of Numerical Taxonomy’ 1985, submitted to the University of Leicester during the tenure of a D.E.S. State Studentship. For this work I drew extensively on interviews with Professors A. J. Cain, G. A. Harrison, R. R. Sokal and P. H. A. Sneath. I am very grateful to them for their time, interest and encouragement. Without the indefatigable assistance of Jon Harwood, this paper would never have been finished.