Stasis in biology refers to the phenomenon of types of living creatures showing little or no change over long periods of time. Apparent stasis in the fossil record was a major reason behind the punctuated equilibrium theory of Stephen Jay Gould and Niles Eldredge. The phenomenon of stasis has been used as evidence against gradual evolution in general.
- A shrimp-like crustacean dated at 425 million years old was assigned to a living species because it was so similar
- Earthworms are thought to be over 120 million years old