This collection of correspondence, reports, and manuscripts concerns Stalker's research in genetics and evolutionary biology, particularly the evolutionary genetics of Drosophila. Most of the letters are scientific, although the usual academic politics in various departments is mentioned. There is also material on the Society for the Study of Evolution (1970).

The collection includes three accessions: (1) a portion of Lewontin's correspondence files (mainly A-L) and copies of papers acquired in 1979; (2) a 2003 accession with files on various subjects and correspondence with about 30 colleagues, and (3) a substantial 2018 accession of about 60 linear feet that includes correspondence, manuscripts, and subject files. The topics discussed in the letters are numerous, including much on contemporary scientific controversies such as race, Darwin, evolution, intelligence, and biological determinism.