Wild kangaroos discovered to be lefties

Humans and monkeys take note. We might no longer be special when it comes to "true" handedness. Once thought to be a peculiar trait found only in primates, researchers who painstakingly followed kangaroos in the wild and discovered, to their surprise, that they, too, prefer to use a certain hand. Their left hand, to be precise. This discovery, which, of course, still has to be independently confirmed, could open the doors to closer scrutiny of the brains of these marsupials, who are known to bring down drones when annoyed.

We might take our left or right handedness for granted, but apparently, it's a big thing in science. In particular, to find it in other animals is a big thing. For a time, true handedness in mammals was considered to be a unique feature found in primates, like you and me. Many have, naturally, thought to challenge that assumption. The very same researchers, for example, observed a bit more handedness in walking frogs compared to jumping ones.

Marsupials, like kangaroos, are taken to be a very special case. They are mammals, true, but it turns out that their brains do not have the same bridges that form between the left and right hemispheres of the brain, which is considered to give rise to handedness. The researchers saw subtle signs of handedness in marsupials that walked on fours, like short-tailed opossums and sugar gliders. But, being bipedal, kangaroos are again a special case.

Observing the animals in the wild, particularly in Australia and Tasmania, Yegor Malashichev of Saint Petersburg State and his band of researcher observed that the kangaroos, particularly the eastern grey and red ones, are dominantly left-handed. Or rather, the prefer to use their left hands for certain types of actions, like picking a leaf or bending a tree branch. Curiously, one particular kind of kangaroo, the red-necked wallabies, use different hands for different types of tasks, left for more fine movement and right for strength.

Things get curiouser and curiouser when you consider the kangaroos that don't exhibit handedness. Wild kangaroos that spend most of their time in trees, for example, show less of that. Even more peculiar, kangaroos in captivity don't develop this traits either. Suffice it so say, scientists now have a lot of work ahead of them in unraveling this handedness mystery. Let's just hope they don't use drones to do so.

SOURCE: EurekAlert