In 1935, Stebbins was offered a genetics research position at the University of California, Berkeley working with geneticist E. B. Babcock. Babcock needed assistance with a large Rockefeller-funded project characterizing the genetics and evolutionary processes of plants from the genus "Crepis" and was interested in developing "Crepis" into a model plant, to enable genetic investigations similar to those possible in the model insect "Drosophila melanogaster". Like the genera that Stebbins had previously studied, "Crepis" commonly hybridized, displayed polyploidy (chromosome doubling), and could make seed without fertilization (a process known as apomixis). The collaboration between Babcock and Stebbins produced numerous papers and two monographs. The first monograph, published in 1937, resulted in splitting off the Asiatic "Crepis" species into the genus "Youngia". The second, published in 1938, was titled "The American Species of Crepis: their interrelationships and distribution as affected by polyploidy and apomixis".