Figure 3
Mutant flies have lower relative fitness in a co-culture competition assay. We determined the relative fitness of mutant and wild-type individuals through a co-culture competition test lasting five generations at 25°C. For this test, we had obtained flies isogenic and homozygous for Hsp83P/P and Hsp83+/+ from the Okayama, Tokyo, and Ivory Coast populations, as described in the main text. We seeded three co-cultures with an equal number of flies of the mutant and wild-type genotype in three parallel co-culture competition experiments started with individuals from the Okayama (filled diamonds), Tokyo (filled cycles), and Ivory Coast population (filled triangles). We seeded two further co-culture competition experiments with lower percentages of mutant flies (30 and 10 percent, open diamonds) from the Okayama population. Each seeding population comprised 100 flies. We genotyped fifty flies in each generation. Note the consistent decrease in allele frequencies in most lines as time progresses.