Rajasaurus, the Deadly Indian Dinosaur

Also known as theropods, meat-eating dinosaurs—including raptors, tyrannosaurs, carnosaurs, and too many other -saurs to list here—had a wide distribution during the later Mesozoic Era, from about 100 to 65 million years ago. An otherwise unremarkable predator, except for its small head crest, Rajasaurus lived in what is now modern-day India, not a very fruitful location for fossil discoveries. It has taken over 20 years to reconstruct this dinosaur from its scattered remains, discovered in Gujarat in the early 1980s. (Dinosaur fossils are relatively rare in India, which helps explain why the regal word Raja, meaning prince, was bestowed on this carnivore. Oddly enough, the most common Indian fossils are ancestral whales dating from the Eocene epoch, millions of years after the dinosaurs went extinct!) Why did Rajasaurus possess a head crest, a rare feature in carnivores that weighed in the one-ton-and-over range? The most likely explanation is that this was a sexually selected characteristic, since colorfully crested Rajasaurus males (or females) were more attractive to the opposite sex during mating season—thus helping to propagate this trait through succeeding generations. Its also worth noting that Carnotaurus, a close contemporary of Rajasaurus from South America, is the only identified meat-eating dinosaur with horns; perhaps there was something in the evolutionary air back then that selected for this characteristic. It may also be the case that the crest of Rajasaurus flushed pink (or some other color) as a means of signaling other pack members. Now that weve established that Rajasaurus was a meat-eater, what, exactly, did this dinosaur eat? Given the paucity of Indian dinosaur fossils, we can only speculate, but a good candidate would be titanosaurs—the gigantic, four-legged, small-brained dinosaurs that had a global distribution during the later Mesozoic Era. Clearly, a dinosaur the size of Rajasaurus couldnt hope to take down a full-grown titanosaur all by itself, but its possible that this theropod hunted in packs, or that it picked off newly hatched, elderly, or injured individuals. Like other dinosaurs of its kind, Rajasaurus probably preyed opportunistically on smaller ornithopods and even on its fellow theropods; for all we know, it may even have been an occasional cannibal. Rajasaurus has been classified as a type of large theropod known as an abelisaur, and was thus closely related to the eponymous member of this genus, the South American Abelisaurus. It was also close kin to the  comically short-armed Carnotaurus mentioned above and the supposed cannibal dinosaur Majungasaurus from Madagascar. The family resemblance can be explained by the fact that India and South America (as well as Africa and Madagascar) were joined together in the giant continent Gondwana during the early Cretaceous period, when the last common ancestor of these dinosaurs lived. Name: Rajasaurus (Hindi/Greek for prince lizard); pronounced RAH-jah-SORE-us Habitat: Woodlands of India Historical Period: Late Cretaceous (70-65 million years ago) Size and Weight: About 30 feet long and one ton Diet: Meat Distinguishing Characteristics: Moderate size; bipedal posture; distinctive crest on head