Answer:The 'Big Five' mass extinctions
End Ordovician (444 million years ago; mya)
Late Devonian (360 mya)
End Permian (250 mya)
End Triassic (200 mya) – many people mistake this as the event that killed off the dinosaurs. ...
End Cretaceous (65 mya) – the event that killed off the dinosaurs.
Step-by-step explanation: