That’s an astonishing 2-3 kilograms a day. But they will have to grow by one ton a year until their adults. When they are newly hatched, they only weigh a few kilograms. They hide beneath a dense layer of ferns and start their life-long obsession with eating.
After hatching, for the next few months, they need the cover of the deep forests and their only chance of survival will be to hide to predators among the vegetation. When they are newly hatched, they usually rest for an instant and then, along with other hatchlings, head for the deep forest as fast as their legs can carry them. Seismosaurus, a synonym of Diplodocus, was 39 meters (130 feet) long on average, making it one of the longest animals that has ever existed, rivaled only by Supersaurus and Argentinosaurus. Other potential Diplodocus specimens, as Seismosaurus, were 50 feet (15 meters) longer, making Diplodocus perhaps one of the longest dinosaurs ever.