Lecture 4 – Speciation

Lecture 4 – Speciation - Lecture 4 Speciation...

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Lecture 4 – Speciation A. Species - How do you get new species? - Species = all individuals of a population that can interbreed to produce fertile offspring Doesn’t fit all organisms because bacteria don’t have sexual reproduction Linnaeus (Carol Von Linne) was the first person to come up with a definition for species. He used to work kind B. Allopatric Speciation Allopathic = other country (associated with geographic isolation) - Geographic sep aration - Geographic barriers (fig. 20-6) 2 islands s ep arated by an oce an so they can’t bre ed 2 m ountaintops with land barrier Two lakes s ep arat ed by a land barrier (pupfish story) o In Nevada a nd Southern California is Death Valley. 10,000 years a go there was a glac there that m elted into hug e ass lakes. They eventually dried up in to lots of little lake with high salt (harsh environ m e nts). There are now over 20 species of pupfish (this h app en ed in 10,000 years) o This is divergent evolution North America and South America, Pana m anian land bridge that formed 3 million yea a go. Species (crabs) are separated on either side of the strip but there is no
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This note was uploaded on 05/30/2008 for the course BS 131 taught by Professor Smith during the Spring '08 term at University of the Sciences in Philadelphia.

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Lecture 4 – Speciation - Lecture 4 Speciation...

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