Aaron Franklin Shull (1 August 1881 – 7 November 1961) was an American zoologist and professor at the University of Michigan.
He began to examine sex determination in rotifers and conducted experiments on mutation induction and crossing in Drosophila.
He also conducted experiments on insect biology and took a special interest in polymorphisms such as in the presence or absence of wings in aphids.
He would point out that W. L. McAtee showed from stomach contents of birds that mimics and models were eaten in proportion to their availability.
In his teaching he believed that there had to be specific principles including cell organization, genetics, systematics and distribution rather than merely descriptions of "type specimens".