More than 100 million years ago, Australia was home to a unique blend of predatory dinosaurs. The latest to be added to the mix—thanks to a single
neck vertebra (pictured above) that was found in Victoria and described today in Biology Letters—is a bizarre class of crocodile-snouted
carnivores called spinosaurs. These peculiar dinosaurs have previously been found in South America, Europe, Africa, and Asia, and the Australian fossil
closely resembles a spinosaur known as Baryonyx from England. Combined with other fragmentary skeletons attributed to tyrannosaurs, raptors, and
allosaurs, this as-yet-unnamed spinosaur may help
paleontologists figure out when different dinosaur lineages arrived in Australia and, consequently, when and how the continent split from other land
masses 80 million years ago. Prior to that time, all the southern continents were merged in a supercontinent known as Gondwana, and the new find—combined with other dino discoveries that indicate that Australian dinosaurs more closely resemble their counterparts in South America rather than
Africa—suggests that Africa may have been the first to split off.
See more ScienceShots.