SYDNEY (AFP) – Scientists stalking a small marsupial through a remote Australian rainforest say they may have found a clue to the mystery of why its bigger kangaroo cousins hop instead of walk.
Kangaroos and closely related wallabies are the only large animals to hop upright on two legs, researchers from Australia’s Flinders University said yesterday, but why remains a mystery.
They believe the answer may lie with the small musky rat-kangaroo, a bush-dwelling marsupial weighing about the same as a loaf of bread.
Musky rat-kangaroos are a distant ancestor of the larger kangaroo species that famously roam the country’s outback.
Researcher Amy Tschirn said musky rat-kangaroos – named for their pungent scent – were the only member of the “macropodoid” family that did not hop.
“As the only living macropodoid that doesn’t hop, the musky rat-kangaroo provides a crucial insight into how and when the iconic hopping form of locomotion evolved in Australia.”
Scientists tracked the creatures, also known as “muskies”, through the tropical rainforests of far-northern Queensland state.
They observed the creatures moving in a “bounding” motion – hopping with their back legs while their front paws remained on the ground.
It suggested a kind of mid-point in the evolutionary journey from walking on all fours to hopping on two, the researchers said.
