Whatever their limited use, the consensus in recent years seemed to be that they were vestigial, hanging around as an evolutionary remnant from T. rex's ancestors, a little like the wings of flightless birds. read more
Pound for pound, this study concludes, T. Rex's arm muscles were over three times more powerful than those of an adult human! There's also a fair degree of misunderstanding about the range of T. Rex's arm motion and the flexibility of this dinosaur's fingers. read more
Rex's arms were fairly limited in their scope--they could only swing across an angle of about 45 degrees, compared to smaller, more flexible theropods like Deinonychus--but then again, disproportionately small arms wouldn't require a wide angle of operation. read more
Tyrannosaurus rex arms are very small relative to overall body size, measuring only 1 meter (3.3 ft) long, and some scholars have labelled them as vestigial. The bones show large areas for muscle attachment, indicating considerable strength. read more