Recent research on the Tiktaalik fossil, a 375-million-year-old fish, has illuminated a significant phase in the evolutionary transition from water to land. Led by Penn State biologist Tom Stewart ...

Tiktaalik roseae had fish-like fins, a flattened skull (similar to a crocodile), and is thought to have lived in shallow water, using its fins to prop itself up ...

Around 400 million years ago, a sea creature—most likely a lobe-finned fish such as Tiktaalik—took the first, tentative steps on dry land. This transition led to the rise of all terrestrial tetrapods, ...