feb 2, 1972 - Punctuated Equilibrium
Description:
 He is most acclaimed for his theory of punctuated equilibrium, which was developed with Niles Eldredge in 1972 (PBS).  This is a theory in the field of evolutionary biology.  It states that once a species appears in the fossil record they will become stable; meaning that they show very little evolutionary change for most of their geological history (PBS).  This state is referred to as stasis. 
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