Minda Berbeco's picture

Answer Monday!

Ichthyosaurus image made available with thanks by UCMP

Last week's Fossil Friday turned out being harder than expected! We had a lot of guesses: durodon, mosasaurus, dakosaurus ... sloth. But no, Mackinz and Dan Coleman once again led the pack with...Ichthyosaurus.

From the UCMP website:

"Rare fossils have been found that show ichthyosaurs actually giving birth to live, well-developed young; ichthyosaurs never had to leave the water to lay eggs. In fact, from their streamlined, fishlike bodies, it seems almost certain that ichthyosaurs could not leave the water. Yet they still breathed air and lacked gills, like modern whales."

And who is its closest relative? That was a trick question!

Again from UCMP:

"Ichthyosaurs were not dinosaurs, but represent a separate group of marine vertebrates. Because ichthyosaurs were so specialized and modified for life in the ocean, we don't really know which group of vertebrates were their closest relatives. They might have been an offshoot of the diapsids—the great vertebrate group that includes the dinosaurs and birds, the pterosaurs, the lizards and snakes, and many other vertebrates. On the other hand, some have suggested that the ichthyosaurs were descended from a distant relative of the turtles."

Thanks for Dan and Mackinz for guessing correctly! Stay tuned for the next Fossil Friday. In honor of Halloween we'll be having an all-skull October!