Too heavy to hop: Extinct giant Kangaroo walked on two feet

They roamed Australia while mammoths and Neanderthals lived in Europe - and it now seems they did so by putting one heavy foot in front of the other. An extinct giant kangaroo that lived in the Australian outback 100,000 years ago was too heavy to hop, scientists have claimed. The extinct “sthenurine” family of giant kangaroos stood at 2.7m tall and had a round rabbit-like face. It is believed to have weighed up to 250kg and was three times the size of the largest present-day kangaroos. The study, published in the journal Plos One, is a detailed comparison between the size and shape of the bones found in living kangaroo species and those of the sthenurines, which died out some 30,000 years ago.

Obviously you’re going out on a limb when you’re proposing something about an extinct animal. But all the data fit.

Lead researcher Professor Christine Janis, from Brown University in Providence, U.S.

The early sthenurines, which were smaller, probably started walking short, slow distances on their hind legs as an alternative to using all fours. Then, as they evolved to become bigger and stockier, they may have become distance walkers and lost the ability to hop. But even modern-day kangaroos don’t hop exclusively. They hop to cover long distances, but when they forage for food on the ground they are more likely to use a pentapedal walk, putting all four feet on the ground and using their tail as a fifth limb to propel them forward.

Science