We've learned an awful lot about Tyrannosaurus rex since the first fossils were found. Strangely, we've never seen a fossil of a baby T. rex. So for the new exhibit T. rex: The Ultimate Predator opening March 11 at the American Museum of Natural History, paleontologists had to do a bit of educated guessing when constructing models of a T. rex hatchling and a juvenile dinosaur. -via Laughing Squid