Imagine if the shape of your head changed with the foods that you ate. That's what a team of paleontologists now thinks happened to the long-necked sauropod dinosaur, Diplodocus, which also was one of the least intelligent dinosaurs. Its head might have been interesting, in terms of shape, but previous studies suggest there wasn't a lot of brain power in it. But, as for all animals, it evolved what it needed for survival.

Diplodocus was a huge, hefty dinosaur that lived towards the end of the Jurassic Period around 150 million years ago in North America.

Carnegie Museum of Natural History Assistant Curator of Vertebrate Paleontology Matthew Lamanna and colleagues made the determination after analyzing the skull of a juvenile Diplodocus that was recently rediscovered in the museum's collections. The researchers were surprised that this head was so different from that of adults of the same species.

The scientists think the changes occurred due to diet. Mammals with narrow snouts use them to choose specific, relatively nutritious plant parts, while blunt-snouted mammals tend to indiscriminately “mow down” low-growing plants. The young dinosaurs must have been pickier eaters, browsing more selectively than their adult relatives did. The dinosaurs probably all ate different foods to avoid competing with each other.