Original URL: http://www.theregister.co.uk/2011/06/29/headbutt_dino/

Dwarfish two-legged dino 'was greatest head-butter ever'

Glasgow not yet built at the time

By Lewis Page

Posted in Science, 29th June 2011 15:39 GMT

A bipedal dinosaur about the size of a German shepherd has been crowned the all-time headbutt champion of the world by Canadian boffins.

Researchers in Alberta, following extensive analysis of the skulls of various species which are known to indulge in headbutting, say that the herbivorous pachycephalosaur Stegoceras validum had the winning bonce. Modern species which routinely go noggin-on-noggin to settle disputes were simply nowhere against the advanced design features sported by the short two-legged prehistoric contender.

Llamas and giraffes are particularly soft puffs, according to Dr Eric Snively, one of the experts who carried out the cranium-clash research. A llama could easily crack its skull against that of another, and giraffes' efforts plainly aren't serious at all.

“If giraffes do manage to butt heads, they can knock each other out because their anatomy isn’t built to absorb the collision as well as something like muskox or big horn sheep.”

Even horny sheep, however, would stand little chance if transported back in time to the favourite pub of Stegoceras validum, there to spill his pint or inadvertently find his lady in their field of vision. Though small, the ancient biped would emerge from any head-to-head encounter in fine shape.

“It’s pretty clear that although the bones are arranged differently in the Stegoceras, it could easily withstand the kinds of forces that have been measured for the living animals that engage in head-butting," says Snively's associate Dr Jessica Theodor. Theodor believes that the primitive bean-battlers, like many modern day species, would knock noggins in disputes over females.

Snively and Theodor's paper Common functional correlates of head-strike behavior in the pachycephalosaur Stegoceras validum (Ornithischia, Dinosauria) and combative artiodactyls is published in PLoS One. ®