When paleontologists unearthed the skeleton of a 70-million-year-old titanosaur in Madagascar in the late 1990s, they also recovered something that had been missing from previous such finds: a skull that matches the body.
Titanosaurs form one group of sauropod dinosaurs, the massive, four-legged plant eaters that had long necks and tails. Most types died out more than 100 million years ago, but titanosaurs were more successful. They stuck around until the extinction of all dinosaurs about 65 million years ago, and their fossils have been found on every continent except Antarctica.
Scientists have described almost three dozen types of titanosaurs, says Kristina Curry Rogers, a vertebrate paleontologist at the Science Museum of Minnesota in St. Paul. Until recently, researchers knew most of these species only from skeletal fragments and isolated bits of skull.