BIOL 1001 Lecture Notes - Lecture 8: Collared Flycatcher, Allopatric Speciation, Fire-Bellied Toad
Document Summary
Explain why allopatric speciation rates are often high in archipelagos. Archipelagos is a cluster of islands with many opportunities for isolation. The more isolation, the more allopatric speciation increases. Leads to large number of closely related species in the same geographical area all ascended from same mainland species, known as species clustered or adaptive radiation. Adaptive radiation is the evolution of many species from a common ancestor. In the galapagos island, darwin observed finches, 13 finches all with different beak sizes which had many similarities with the mainland finches. Recently diverged species come back into contact. In allopatric speciation, when species are diverged and underwent genetic differentiation, isolation is supposed to evolve, however, if isolation did not evolve perfectly, hybrids form. Postzygotic isolation exists and difference in chromosomal numbers also exists as well as absence of prezygotic isolation. Explain what the evolutionary phenomenon known as reinforcement is.
