Baby tyrannosaurs were ‘size of Border Collie dog’ when taking first steps

An artist’s impression of the baby tyrannosaur with the one of the fossils discovered (Julius csotonyi/Greg Funston/PA)

Baby tyrannosaurs were only the size of a Border Collie dog when they took their first steps, a team of palaeontologists has discovered.

Led by Dr Greg Funston, a University of Edinburgh researcher, the team examined fossilised remains of a tiny jaw bone and claw which had been found in Canada and the US.