The Austrian biologist Paul Kammerer was an outspoken proponent of the theory of inheritance of acquired characteristics (Lamarckism) during the time in which Mendelian theory was becoming deeply entrenched in biology. His major research efforts, straddling the First World War, centered on experiments performed on salamanders and on the midwife toad, and seemed to provide empirical support for a Lamarckian mechanism in evolution. He also developed a monistic "law of seriality," in which he attempted to explain coincidence as the product of a higher order natural law. A Socialist, Kammerer was widely regarded as a brilliant scientist, but for scientific, personal, and political reasons, he engendered as much antagonism as support, preventing him from ever obtaining a regular university appointment. His career ended tragically in allegations of fraud, followed by his suicide. The Kammerer Papers is comprised of photocopies of materials that document the brief, but controversial career of a non-Darwinian evolutionary biologist. The bulk of the collection consists of photocopies of articles by Kammerer, often from obscure newspapers or periodicals, along with a small number of letters to his friend Hugo Iltis, the geneticist and biographer of Mendel. Nearly all of these pertain to the Kammerer's experiments with amphibians to test Lamarckian inheritance or to his other biological theories. The collection also includes a small number of items dating from after Kammerer's death, but relating to his life and work, including two letters from his former supervisor Hans Przibram, a letter from Hugh Iltis (Hugo's son) to Arthur Koestler and the reply, and a brief biographical reminiscence of Kammerer written by Hugo Iltis.

One of the most important natural historians in nineteenth century Britain, Charles Darwin provided the first compelling mechanism to account for organismal evolutionary change. Although lacking a coherent model of heredity, Darwin's natural selection has exerted an enormous influence over the biological sciences and since the introduction of Mendelian genetics, had remained the key unifying principle in the discipline. The APS Darwin Papers are a large a valuable assemblage of Darwin's correspondence with scientific colleagues, including Charles Lyell and George J. Romanes. They are included in the print version of the Correspondence of Charles Darwin (Cambridge Univ. Press).

A geneticist and educator, Philip Macdonald Sheppard was head of the Department of Genetics at the University of Liverpool from 1963-1976. His research centered on polymorphism, mimicry, blood groups, genetic disease, and speciation, using a variety of subjects, including the gastropod Cepaea nemoralis, butterflies, and humans. He may be best remembered for his classic study of industrial melanism in the pepper moth Biston betularia. The Sheppard Papers (1911-1983; bulk dates, 1940-76) contain correspondence, subject files, notes, and manuscripts that document Sheppard's life as a geneticist. The earliest piece in the collection is a lepidopterist's notebook from 1911, possibly J. R. Hobhouse's, however the bulk dates from 1940 to 1976, Sheppard's most productive and influential years. Among other things, these materials document Sheppard's research on the Scarlet Tiger moth, swallowtail butterflies, and ABO blood groups in humans, as well as his position as head of the Department of Genetics at the University of Liverpool.