  The anti-reductionist consensus has not gone unchallenged (see Sarkar 1989, 1992 and 1998, Schaffner 1993, and Waters 1990 and 2000). According to critics, the chief objections supporting the consensus are mistaken. The unconnectability objection rests on the assumption that classical genetics took the relationships between genes and phenotypic traits to be simple one-to-one relationships. But classical geneticists knew better.  Consider what Sturtevant, one of Morgan's star students and collaborators, had to say about genes and eye color: