Some extinct or endangered species in the Biodiversity Hall. © AMNH   Pick a Theory, Any Theory #1 - Climate Change Some kind of climate change probably figured into all of the mass extinctions and is thought to have been a major factor in a least three of them: the late Ordovician, the late Devonian and the end of the Permian. Climate change alters ecological niches, favoring some plants over others. Supporting this theory are sediments characteristic of the glaciers typical of those “Ice Ages,” which have been found under the floor of the North Sea and elsewhere. There’s also evidence of the extinction of groups adapted to warm climates during these periods.      7 of 17