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To: 2MAR$ who wrote (78)	10/15/2014 10:59:23 PM
From: Brian Sullivan	Read Replies (1) \| Respond to of 150

Giant, Extinct Kangaroos may have walked around on two feet instead of hopping Written by Betty Laseter on 16 Oct 2014 Brown University researchers have suggested that the ancestors of modern-day kangaroos, giant marsupials with rabbit-like faces, might have walked upright on two feet. The study claims that considering the bone structure, the earlier kangaroos were not hopping. The earlier species had enormous size and could be considered as part of the extinct family of sthenurine kangaroos that once roamed the Australian outback from about 100,000 to 30,000 years ago. Lead researcher Christine Janis, a professor of ecology and evolutionary biology at Brown University in Rhode Island that sthenurine kangaroos were likely bad hoppers. "Modern large kangaroos are not the 'norm' for kangaroos. In fact, they appear to be more like a cheetah in comparison with other large cats — slimly built and streamlined for specialized, fast locomotion," Janis told Live Science. Janis and her colleagues traveled to about half a dozen museums around the world, measuring the bones of 140 kangaroos, including sthenurine and wallaby skeletons. The largest kangaroo (Procoptodon goliah) weighed an estimated 529 pounds (240 kilograms), or about three times the weight of modern day kangaroos. The enormous size of the species may have prevented them from hopping, and analyses show that their bodies were configured differently than their modern ancestors. For instance, the anatomy of sthenurines suggests they held their bodies in an upright position, and could support their weight on one leg at a time by using their large hips, knees and stabilized ankle joints. The sthenurines' bone structure, the new study shows, kept them mostly earthbound. "Apart from their massive size, solid bodies and relatively short faces, these extinct kangaroos lacked the specializations for high-speed hopping seen in modern-day kangaroos, such as a flexible spine, proportionately long legs, and large tail," said Karen Black, an Australian Research Council postdoctoral fellow of palaeontology at the University of New South Wales in Australia, who was not involved in the study.