1. Punctuated Equilibrium

2. Harvard paleontologist Stephen Gould, Niles Eldridge and Steven Stanley said, “The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology. The evolution trees that adorn our textbooks have data only at the tips and nodes of their branches, the rest is inference, however reasonable not the evidence of fossils.”

3. In an attempt to explain the gaps at the species level, they conceived of the “punctuated equilibrium hypothesis.” This hypothesis proposes that evolution occurred in spurts that were so fast that no fossil evidence was left.

4. Think Critically Is the hypothesis based upon the assumption that the gaps in the fossil record are factual? The hypothesis demands that there is no evidence. Is this good science?

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