George Gaylord Simpson, 1956 (courtesy American Philosophical Society Library).

George Gaylord Simpson’s “Night Thoughts on Leaving the American Museum,” 1959

George Gaylord Simpson (1902-1984) was a leader in twentieth century vertebrate palaeontology, and he contributed to making the American Museum of Natural History a powerhouse in the field. In 1959, Simpson left his job at the museum in a bitter dispute with its management. Simpson never published a rationale for his resignation, but he secretly wrote one. After his first day unemployed, Simpson penned a…

Theodosius Dobzhansky (1900-1975) was an experimental population geneticist and Soviet émigré to the US. In 1943, he visited Professor Andre Drefus in Sao Paolo as part of a US “good neighbour” programme. In this photograph, Dobzhansky (centre) and two unnamed Brazilian colleagues are trapping Drosophila fruit flies in nearby forest. Dobzhansky was key to the synthesis period.

Descended from Darwin (book)

The synthesis period in evolutionary studies (most people call this the “evolutionary synthesis” of the 1930s and 1940) has had a standard narrative for many years, but pressure is increasing for a revision. This book, Descended from Darwin, began as a conference at the American Philosophical Society Library, Philadelphia (22–23 October 2004). The goal of the conference was to investigate how scholarship might move forward. Conference…