““If A was tightly linked to B, and very loosely linked to C, Sturtevant reasoned, then the three genes must be positioned on the chromosome in that order and with proportional distance from each other: A.B..........C. If an allele that created notched wings (N) tended to be co-inherited with an allele that made short bristles (SB), then the two genes, N and SB, must be on the same chromosome, while the unlinked gene for eye color must be on a different chromosome. By the end of the evening, Sturtevant had sketched the first linear genetic map of half a dozen genes along a Drosophila chromosome.””
