New research has revealed that the evolution of the complex,
weight-bearing hips of walking animals from the basic hips of fish was a much
simpler process than previously thought.
Tetrapods, or four-legged animals, first stepped onto land
about 395 million years ago. This significant change was made possible by
strong hipbones and a connection through the spine via an ilium - features that
were not present in the fish ancestors of tetrapods.
In a study published in the journal Evolution and
Development, Dr Catherine Boisvert of the Australian Regenerative Medicine
Institute at Monash University, MacQuarie University's Professor Jean Joss and
Professor Per Ahlberg of Uppsala University examined the hip structures of some
of human's closest fish cousins.