After analyzing a number of factors and fossil specimens, the researchers came to the conclusion that the extinction of ichthyosaurs 94 million years ago caused abrupt climate change.
As a result the deep areas of the oceans, inhabited by reptiles, is practically without oxygen. The consequence was a change in the habitat of ichthyosaurs, which led to starvation and low survival of their offspring.
The researchers note that the extinction of these reptiles occurred quickly. Along with them are victims of climate change and become other organisms. For several hundred years, the niche occupied ichthyosaurs mosasaurs — the relatives of modern lizards.
Ichthyosaurs appeared 248 million years ago. In many respects they resembled sharks were viviparous. The average length of the ichthyosaur did not exceed four meters.