16.3+Speciation_6th

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 * ~Speciation is the formation of new species. rm**

Quick Notes:
 * Relative frequencies of alleles in populations can be changed by natural selection and chance events.
 * A genetic change that occurs in an individual can affect the entire population. rm

Reproductive Isolation

 * 1) When members of two populations cannot interbreed or create fertile offspring
 * 2) Can develop from behavioral, geographic, and temporal isolation
 * 3) There must be a genetic change to complete the specicaton process in a species m

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 * 1) Occurs when two species capable of interbreeding but have difference in courtship rituals or other reproductive strategies that include behavior
 * 2) Can be used to help distinguish one species from another---ex. two species of cricket are nearly identical, except for their mating song; they are of different pitches. r

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media type="custom" key="3434376"_ media type="custom" key="3434386" m media type="custom" key="3434418" _media type="custom" key="3434440" > Example- 3 species of orchid release pollen on different rotating days so they can't reproduce. r
 * 1) Two populations separated by geographic barriers such as rivers, mountains, or bodies of water.
 * 2) Does not guarentee formation of new species
 * 3) Barriers are related to the ability of organisms. For example, rivers can separate land constricted animals but not birds.
 * 4) Can create hybrid species
 * 5) Also called allopatric isolation. r
 * 1) Two or more species reproduce at different times

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 * 1) Refers to organisms whose geographic ranges overlap or are identical
 * 2) Becomes sister species if they are very similar
 * 3) Sym- means alike, similar, fellow. -patric means homeland or fatherland
 * 4) not geographically isolated
 * 5) species are created by genetic variations from a parent species. rm

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//Helpful// //Links:// [] [|http://evolution.berkeley.edu/evolibrary/article/0_0_0/ evo_42] [] [] rm



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 * Other Sources:**

**Meredith and Robinmedia type="custom" key="3443200"** m