Editing Modern synthesis (20th century) (section)

===Morgan's fruit flies, 1912===
{{main|Thomas Hunt Morgan}}

Thomas Hunt Morgan began his career in genetics as a [[Saltation (biology)|saltationist]] and started out trying to demonstrate that mutations could produce new species in fruit flies. However, the experimental work at his lab with the fruit fly, ''[[Drosophila melanogaster]]''{{efn|Morgan's work with fruit flies helped establish the link between Mendelian genetics and the [[chromosome|chromosomal]] theory of inheritance, that the hereditary material was embodied in these bodies within the cell nucleus.<ref name="auto">{{harvnb|Bowler|2003|pp=271–272}}</ref>}} showed that rather than creating new species in a single step, mutations increased the supply of genetic variation in the population.<ref name="auto"/> By 1912, after years of work on the genetics of fruit flies, Morgan showed that these insects had many small Mendelian factors (discovered as mutant flies) on which Darwinian evolution could work as if the variation was fully continuous. The way was open for geneticists to conclude that Mendelism supported Darwinism.{{sfn|Provine|2001|pp=120–121}}

{{anchor|Woodger}}