ANT 205 Lecture Notes - Lecture 6: Parapatric Speciation, Allopatric Speciation, Species Problem
Document Summary
Microevolution: effects of forces of evolution from generation to generation. Macroevolution: speciation -- the generation of a completely new species throughout generations. If two organisms can interbreed and produce fertile offspring, then they are members of the same species. Natural selection keeps species distinct from each other. Speciation: the process by which new species come into existence. Selection alone creates different phenotypes and different species. Cladogenesis (clay"-dough-genesis): branching evolution caused by a new species resulting from an ancestral species splitting in two. Ecological niche: the way an organism makes a living . Adaptive radiation: rapid diversification to fill niches. Helps us understand our species"s place in the context of evolutionary history. Evolutionary relationships traced through time using homology. Both terms describe similar structures in different organisms. Ancestral traits: inherited from a remote ancestor; usually shared with living relatives. Two legs inherited from distant ancestors, shared with living relatives.
