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Evolution of Reproductive Isolation in Allopatric and Sympatric Populations
A. Benedict Soans, David Pimentel and Joyce S. Soans
The American Naturalist
Vol. 108, No. 959 (Jan. - Feb., 1974), pp. 117-124
Stable URL: http://www.jstor.org/stable/2459740
Page Count: 8
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Experiments were designed to measure the rate of evolution in sympatric (30% gene flow) and allopatric populations of houseflies under similar types of divergent selection (+ or - geotaxis). Under 5% selective pressure on both sympatric and allopatric populations, both diverged rapidly, with the allopatric populations evolving slightly faster during the 38 generations of the experiment. Incipient reproductive isolation occurred in both sympatric and allopatric population systems. In one test, a greater tendency toward reproductive isolation existed in sympatric populations than in allopatric ones.
The American Naturalist © 1974 The University of Chicago Press