BIOLOGY 1M03 Lecture Notes - Lecture 1: Sympatric Speciation, Nuptial Gift, Ring Species
Document Summary
Sexual selection: honest advertising, male-male competition, resource contribution / nuptial gift, sensory exploitation / sensory bias. Sympatric speciation: via disruptive selection, via autopolyploidization, via allopolyploidization. Hybrid zones: hybrids could facilitate gene flow, or not, movement of hybrid zones, formation of new hybrid species, possible extinction of parental species. Genetic isolation happens when populations become physically separated. Alloparty (literally different countries refers to populations or species that live in different places. Physical isolation occurs by dispersal or vicariance. Dispersal occurs when a population moves to a new habitat, colonizes it, and forms a new population. Vicariance occurs when a physical barrier splits a widespread population into subgroups that are physically isolated from each other. Then, colonists float to an island on a raft. Finish with two populations isolated from one another. Island population begins to diverge due to genetic drift, natural selection, and mutation. A change in river flow isolates a population begins to diverge.