The fossil fills the void between the dolphin-like creatures that swam in the sea, and the terrestrial ancestors that scientists long predicted had existed. The first amphibious ichthyosaur had seal-like flippers which allowed it to move effectively on land and in water.
Bridging the Ichthyosaur evolutionary
Lead scientist Professor Ryosuke Motani of the University of California, writing in the journal Nature, claimed that the scientists had uncovered a fossil “showing the transition” from terrestrial to water-dwelling ichthyosaurs.
The scientists found the remains in Anhui Province, China, and they date from the early Triassic period, about 248 million years ago. The fossil of Cartorhynchus lenticarpus was only 1.5 feet long, making it the smallest known ichthyosaur.
The large flippers were supported by flexible wrists which enabled movement over land. One differentiation that scientists have noticed in Cartorhynchus lenticarpus is its short nose, in contrast to the long snout that most ichthyosaurs had. The researchers have speculated that the short nose may have been an adaptation for suction feeding.
Another feature is its thicker bones, which supports the theory that before leaving land, marine reptiles grew heavier in order to better swim through strong coastal waves.
The Permian-Triassic extinction, otherwise known as the “Great Dying”, was responsible for killing off 96% of all species. Scientists have speculated that it might have been due to global warming.
The newly discovered animal lived around 4 million years after the extinction, which goes to show just how long it took the Earth to recover.
Professor Motani gave a warning as to the present day risks of global warming.
“This was analogous to what might happen if the world gets warmer and warmer. How long did it take before the globe was good enough for predators like this to reappear? In that world, many things became extinct, but it started something new. These reptiles came out during this recovery.”
Could our lack of effective response to global warming lead to another mass extinction? Let’s hope not.