Evidence
Jablonski found that the extinction rate of marine invertebrates was significantly higher in the stage (major subdivision of an epoch – typically 2–10 million years' duration) following a mass extinction than in the stages preceding the mass extinction. His analysis focused on marine molluscs since they constitute the most abundant group of fossils and are therefore the least likely to produce sampling errors. Jablonski suggested that two possible explanations deserved further study:
- Post-extinction physical environments differed from pre-extinction environments in ways which were disadvantageous to the "dead clades walking".
- Ecosystems that developed after recoveries from mass extinctions may have been less favorable for the "dead clades walking".
"Dead Clade Walking" has since appeared in other scientists' writings about the aftermaths of mass extinctions.
Read more about this topic: Dead Clade Walking
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