FOSSIL OF ANCIENT SEA DRAGON DISCOVERED IN JAPAN

It isn't easy to picture what life was like on Earth during the dinosaur era. Nonetheless, we can learn more about the kinds of extinct animals that once lived by examining fossils. Even though many species have been found, new ones are still being discovered regularly. One such discovery occurred recently in Japan. 72-million-year-old fossils of a previously undiscovered mosasaur species—a "sea dragon" indigenous to the Pacific Ocean— have been discovered. 

The fossils were discovered in 2006 in Wakayama Prefecture, close to the Aridagawa River. "It was almost the whole specimen in this instance, which was remarkable," Takuya Konishi, an associate professor at the University of Cincinnati, said. It is the most complete mosasaur discovered in Japan or the northwest Pacific thanks to the skeletal remains. It is distinct from other discovered mosasaur fossils, though. The front flippers of the Japanese species are shorter than the length of its head, while the rear flippers are longer. Konishi said, "I thought I knew them quite well by now." "It was something I had never seen before right away." 

The time of the T-Rex and other well-known dinosaurs was when mosasaurs lived. However, the mosasaur hunted underwater, while its counterparts dominated the land. The new species, Megapterygius wakayamaensis, was assigned to the subfamily Mosasaurinae and is roughly the size of a contemporary great white shark. Researchers think that because of the size of its back flippers, it was able to swim through the water more easily than other sea creatures.

“We lack any modern analogue that has this kind of body morphology—from fish to penguins to sea turtles,” Konishi explained. “None has four large flippers they use in conjunction with a tail fin. It opens a whole can of worms that challenge our understanding of how mosasaurs swim.