Zo 6.4

Rates of Evolution

p. 115-118

Gradualism

?        Small, continuous changes in phenotype can produce __________________________________ among species only by accumulating over many thousands to millions of years

?        Population gradualism – __________________________________________________________

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?        Phenotypic gradualism – __________________________________________________________

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Punctuated Equilibrium

?        Phenotypic evolution is _____________________________________ in relatively brief events of branching ___________________________________ (10,000-100,000 y) followed by much longer intervals of evolutionary ___________________________________ (5-10 my)

?        Explains the ______________________________________________ evolutionary changes exhibited by the fossil record