Illustration of a giraffatitan dinosaur. Giraffatitan was previously thought to be a species of brachiosaurus (B. brancai) but is now thought to belong to a separate genus. These animals were sauropods, four-legged, plant-eating dinosaurs from the Jurassic period. They reached a maximum length of about 26 metres and weighed up to 40 tonnes. The skeletons of Brachiosaurus and Giraffatitan, although coming from different continents (America and Africa, respectively) look almost identical to the untrained eye, so this picture could represent either animal.