BIOLOGY 171 Lecture Notes - Lecture 11: Sympatric Speciation, Allopatric Speciation, Species Problem

• School: U of M
• Department: Biology
• Course: BIOLOGY 171
• Professor: Josephine Kurdziel

Document Summary

Species are real biological entities not just a way to group organisms. Dependent on 2 individuals" ability (or inability) to exchange genetic material by producing fertile offspring. A species represents a closed gene pool. Most widely used and accepted definition of a species is the biological species concept (bsc: species are groups of actually or potentially interbreeding populations that are reproductively isolated from other such groups. Members of different species are reproductively isolated. Bsc shortcomings: time consuming and hard to test in nature, does not apply to extinct species, does not apply to asexual species, does not apply to archaea or bacteria. Morphospecies concept: holds that members of the same species usually look alike: extended to the molecular level. Ring species are populations that are reproductively but not genetically isolated (bsc issue) Ecology and evolution can extend the bsc: ecological species concept. Idea that there is a one-to-one correspondence between a species and its niche.