BIO152H5 Lecture Notes - Lecture 20: Reproductive Isolation, Macroevolution, Gene Flow
Document Summary
Speciation: the process by which one species splits into 2 or more species, many shared characteristics due to shared ancestry. Microevolutionary mechanisms: mutation, gene flow, genetic drift, natural and sexual selection: macroevolution. The origin of new groups of organisms. Mechanisms by which new species originate from existing ones. Species: evolutionary independent group or population differing in morphology, physiology, biochemistry and dna sequence. Before the zygote forms you can block fertilization, continent separation, time difference, temporal, behavioural, mechanical and gamete isolation. Preventing the proper development and functioning of zygote, once formed. Reduced survival, hybrid fertility and decreased chance to: limitations reproduce. Biologi(cid:272)al idea does(cid:374)"t appl(cid:455) to ase(cid:454)uall(cid:455) reprodu(cid:272)i(cid:374)g orga(cid:374)is(cid:373)s, sa(cid:373)e. Also depends on what humans think is similar. Ecological species concept: view species in terms of. Considers range of environmental tolerances: emphasizes the role of disruptive natural selection. As organisms adapt to different environmental conditions.
