A mass extinction event occurred about 542 mya that marks the boundary between Precambrian time and the A. Cambrian Period B. Hadean Period C. Permian Period

The first of the "Big Five" mass extinctions to clearly have a significant asteroid impact component was at 359 mya, in the middle of the A. Holocene Period B. Hadean Period C. Devonian Period

The ______ era had many extinctions because of large variations in climate.A.PrecambrianB.PaleozoicC.CenozoicD.Mesozoic

Following the devastation of End Permian came 'the age of reptiles'; this really covered the entire _________ Era, right up to the extinctions at End Cretaceous. A. Triassic B. Mesozoic C. Phanerozoic

The Cambrian explosion refers toGroup of answer choicesan ancient mass extinction eventthe origin of prokaryotesthe origin of eukaryotesthe invasion of the landthe sudden appearance of animals

End of Permian extincts were complex: 5 events over 5 million years.A. TrueB. False