In the Chondrichthyes, the skull consists of chondrocranium and upper jaw. In the Osteichthyes through mammals, the skull is a fused unit in which the braincase is added to and welded together by a ...

The incomplete skull — a section of the left cheek bone and upper jaw – was found in northern Spain in 2022. The fossil is between 1.1 million and 1.4 million years old, according to research ...

This image shows the upper jaw and skull of Maiabalaena nesbittae. Whales were the first mammals to evolve baleen, and no other mammal uses any anatomical structure even remotely similar to it to ...