The Black Vault - Tiny fossil skulls illuminate dinosaur giant

Palaeontologists have finally found two intact skulls of a massive dinosaur called a titanosaur. However, the skulls are a mere 3.5 centimetres long, as they came from unhatched eggs.

Titanosaurs were sauropods, plant eaters with long necks and heavy tails attached to gigantic bodies. Adults were up to 40 meters long. The largest titanosaur was Argentinasaurus, estimated from an incomplete skeleton to weigh as much as 100 tons, making it the most massive animal ever to walk the land.

Despite their tremendous mass and their wide distribution during the final part of the dinosaur era, knowledge of titanosaurs is sketchy. Most are known only from leg bones, vertebrae, and their distinctive chisel-like teeth.

A few skull bones are known. But they were found separated from one another, so palaeontologists do not know how the skull fitted together. This is a common problem with sauropods, because their comparatively small and fragile skulls usually come away from the massive skeleton after death.