A team of researchers from the University of California, Davis, has discovered in the Chinese province of Ánhui the remains of an ichthyosaur , a marine reptile that lived about 248 million years ago, capable of moving both in water and on land . According to these scientists in an article published in Nature , the specimen represents a link between these dolphin-like animals, which populated the oceans between 245 and 90 million years ago , and their terrestrial ancestors.
“These fossils show that transition,” says Ryosuke Motani, professor of Earth and Planetary Sciences at the aforementioned US institution, who has coordinated the study. This peculiar ichthyosaur from the Triassic period was about 18 inches tall and featured striking anatomical adaptations. Thus, it had unusually long fins and flexible joints, which allowed it to walk more or less like seals. Also, while most ichthyosaurs had a sharp snout, this specimen was short, not unlike that of land reptiles. His bones, too, were thicker.
Motani highlights that the finding has notable implications , since this animal, baptized Cartorhynchus lenticarpus , lived just four million after the Permian-Triassic mass extinction, which occurred 252 million years ago, the most devastating in the history of our planet: in she disappeared more than 70% of terrestrial vertebrates and 95% of marine species.
Experts have wondered how long it took the animals to recover after this event, which in some hypotheses is related to climate change. “If our planet got hotter and hotter, leading many species to extinction, how long would it be before conditions were right for predators like this to reappear? Apparently, this reptile emerged during the recovery process, ”says Motani.
Foto: Ryosuke Motani / UC Davis
