Chilean paleontologists last week presented their findings on a dinosaur with a highly unusual tail. It was discovered three years ago in Patagonia, and its tail has stumped researchers.

Despite what countless fictional adaptations may have implied, aquatic dinosaurs were not confirmed to be a reality until 2020. After analysis of a tail fossil uncovered in Morocco, researchers ...

That is, from the group of dinosaurs that includes t-rex, raptors, and modern birds. The tail was flexible, and different from the fused tails modern birds use for flight. It was chesnut-brown on ...