So Big, So Cosmopolitan

Tyrannosaurus rex was the undisputed giant of all land predators for 90 years, and in that time it developed the aura of a dinosaurian Muhammad Ali. It was, truly, the greatest. But in 1995 paleontologists in Argentina discovered a new dinosaur, called Giganotosaurus, which was probably heavier and certainly as long as the 40-foot, 70-million-year-old T. rex. And this past year, like the second blow of a one-two punch, came the report of another predator the size of a T. rex, this one from Africa.