BIOL 123 Chapter Notes - Chapter 2: Sympatric Speciation, Hybrid Zone, Fire-Bellied Toad
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Sympatric speciation has resulted from nonrandom mating due to sexual. Hybrid zones provide opportunities to study factors that cause reproductive isolation. Figure 24. 14 formation of a hybrid zone and possible outcomes for hybrids over. Figure 24. 13 a narrow hybrid zone for b. variegata and b. bombina in europe. Figure 24. 16 the breakdown of reproductive barriers. The graph shows the pattern of allele frequency changes across the width of the zone near krakow, poland. in lake victoria over the past 30 years may have weakened reproductive barriers between p. nyererei and p. pundamilia. In areas of cloudy water, the two species have hybridized extensively, causing their gene pools to fuse. time. The thick colored arrows represent the passage of time. *all but which of the following are likely to promote sympatric speciation. Answer: gene flow (yes: ecological isolation, temporal isolation, & polyploidy) Radiometric dating of meteorites & moon rocks. Chemical traces in rocks 3. 8 billion years.