T. rex and other tyrannosaurs were huge, dominant predators, but they evolved from much smaller ancestors. The fossilized remnants of the Bisti Beast, or Bistahieversor sealeyi, were found in 1996 in the Bisti/De-Na-Zin badlands near Farmington, N.M. Williamson said the Bisti Beast was a surviving member of a lineage that retained many primitive features from even farther back than when tyrannosaurs underwent their transition to crushing bones. The technology is typically used for the lab's work on defence and national security. The thickness of the skull required stronger X-rays than those typically available to penetrate the fossil, the lab said.

Source: CBC News August 15, 2017 21:22 UTC