Tyrannosaurus rex -- the most fearsome predator ever to have trod the Earth -- had a pint-sized precursor, remarkably similar in appearance but no heavier than a human being, according to a new report from a team of scientists. The creature was what Austin Powers might call T. rex's Mini-Me.

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Raptorex, however, shows that having the jaws as the first line of attack rather than the forelimbs worked for bodies at the much smaller scale, and tens of millions of years before T. rex's giant phase. Like T. rex, raptorex had a bite force so powerful it could chomp through bone.