Did you know that most kangaroos are left handed? As in southpaws like Rocky Balboa. OK, I know. They don’t actually have hands, they have paws. But hands and paws aside, they do have a distinct favor for the left over the right.
There’s been a long-standing factoid circulating around the web that all polar bears are left-handed, but as you may know we have revealed that to be nothing but a misleading falsehood. But unlike that unsupported fact, this one is actually true. Most kangaroos are left-handed, and it’s backed up with scientific evidence that supports its claim. Furthermore, it’s unusual among the animal kingdom.
It’s been a long-held belief that the only animals to exhibit handedness, meaning a predictable preference for one side over the other, was that of primates, such as humans and apes. While there have been unsubstantiated claims of other animals exhibiting this trait, until now nothing has ever been proven. But this handedness among kangaroos is even more pronounced than that of even humans.
The extensive study of kangaroos handedness was published in the journal Current Biology. Lead author of the study, Associate Professor Yegor Malashichev, who is a zoologist at Saint Petersburg State University in Russia (yes, that is Russia, not Australia) and his team observed kangaroos in the wild and made the startling discovery. In fact, they managed to get the highest grades in an assessment designed for primates.
Professor Malashichev and his team studied mobs of kangaroos throughout several locations on mainland Australia and in Tasmania. The team found that eastern greys and the western reds were the most prevalent lefties, while wallabies for example seemed to change their use depending on the particular task they were performing. For example, a task that required physical strength to accomplish had a tendency to use their right arm, while more refined tasks were performed with their left arm. But the kangaroos were overly represented as being left dominant. Other marsupials had no apparent preference for either hand.
What makes this discovery so profound is that their brains are not wired the same as other mammals. In essence they lack the same neural circuitry between the left and right halves of the brain that other mammals do.
According to a special-assessment scale of handedness adopted for primates, kangaroos pulled down the highest grades. We observed a remarkable consistency in responses across bipedal species in that they all prefer to use the left, not the right, hand.
~Project leader Yegor Malashichev