Newton meets Darwin- Evolutionary biomechanics - June 2011

At the 16^th June meeting of the Beds Essex and Herts Branch, Dr John Hutchinson, of the Royal Veterinary College, explained, with the aid of amazing graphics, animation and CT scans how animals walk; it may seem as simple as putting one foot in front of the other, but it isn’t.  Studying the forces which come into play, the positioning of muscles and the necessary strength of those muscles has aided our understanding of why T. rex.  couldn’t have been a fast runner! (Sorry Hollywood).

It was a good evening and the talk was very interesting, particularly with regard to how evolution can be monitored through the gradual changes seen in the shape of the pelvic bone. The talk highlighted that we now understand how the migration of the point of specific muscle attachments during evolution changed as animals moved onto land from a mainly aquatic existence. John explained that elephants walk on their tip-toes and have an extra digit which is buried deep in the fat pad which makes up the majority of their foot, and that while rhinos have a fat pad in their feet, it is much smaller than in the elephant; rhinos do not have the extra digit. Rhinos are very nimble on their toes, but elephants can only manage the “running-walk” gait.

The hip bones of an ostrich and a crocodile were available for the audience to view - the feather-weight ostrich hip girdle surprised many of us - and we had the opportunity to see the effects of infection on elephant foot bones.

It was a fascinating talk, which linked physics (Newton) and biology (Darwin) and was an excellent introduction to evolutionary biomechanics.