The maxim of "to the victor go the spoils" might have started with Tyrannosaurus rex. The great beast, which roamed western North America 65 million years ago, apparently would feast on one of its cousins if it killed the rival in battle, researchers report  online today in PLoS ONE. The team examined dozens of T. rex bones from several fossil collections and found that three foot bones and one arm bone contained gouges (inset) that could have come only from another T. rex. The marks also appear to have come from gnawing, not biting, suggesting they are the result of one dino feeding on another. The researchers think that when two of the giants fought to the death, the survivor would make a meal of the loser—which is similar to what often happens when modern-day carnivores tangle. It's also possible that the dinos merely scavenged on each other. Either way, the study is the first bit of evidence that, along with being a killer and a scavenger, T. rex was also a cannibal.
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