Scientists have found that in the course of evolution, ichthyosaurs reached gigantic proportions in just 2.5 million years. An article about this was published in the journal Science.

The study was led by Martin Sander of the University of Bonn. In the course of it, scientists discovered that the evolutionary paths of ichthyosaurs and cetaceans were very different. In ichthyosaurs, at the beginning of their existence, about 250 million years ago, there was an explosive growth in body size, while whales grew gradually.

In comparison, whales, which are 55 million years old, took 90 percent of that time to reach the size that ichthyosaurs reached in 1 percent of their 150 million-year history.

“We found that ichthyosaurs developed gigantism much faster than whales as the world was recovering from the devastating extinction of the late Permian,” says Lars Schmitz, one of the authors of the work. "It's a welcome glimpse of hope and a sign of resilience in life — under the right environmental conditions, evolution can happen very quickly and life can return to normal again."

In addition, cetaceans and ichthyosaurs had different reasons for the development of gigantism. Whales grew either due to the loss of teeth and the transition to a diet of plankton, or due to the hunt for other predators - both for one and for the other size is important. The sharp increase in the size of ichthyosaurs occurred due to the feeding on ammonites and jawless eel-like conodonts, which existed in abundance, filling the ecological void after the mass extinction at the end of the Permian period.

bbabo.Net