It seems that kangaroos, just like humans, also have hand preferences. A study published on Thursday in the journal Cell Biology has proved that marsupials such as kangaroos have a hand preference. This can be observed in everyday tasks such as eating and grooming and even boxing.
The lead author of the study, Yegor Malashichev from the Saint Petersburg State University (Russia), together with his colleagues analyzed wild kangaroos and observed that in particular red and eastern grey kangaroos have a natural preference for their left hands when they perform certain tasks such as picking leaves, bending tree branches and grooming their noses.
Scientists did not expect kangaroos to show such preferences because marsupial brains do not have the same neural connections between the right and left hemispheres like humans and primates do. This new discovery could help researchers find out more about the mind of the marsupials.
The research team analyzed four species of marsupials from Australia and Tasmania: the red-necked wallaby, also known as Macropus rufogriseus, the eastern gray, the Goodfellow’s tree-kangaroo or Dendrolagus goodfellowi and the red kangaroo.
The trait of left-handedness was especially visible in the cause of eastern grey and red kangaroos. In the case of the red-necked wallabies, they preferred using one hand for some tasks and the second hand for other tasks. They used the right forelimbs for tasks which involved more physical strength and the left forelimb for tasks which required fine movements.
Malashichev said that this research makes investigators look differently at marsupials. Since kangaroos have no link with the primate lineage, this indicates that handedness is something which has evolved independently with the passage of time.
Researchers hope to discover more about handedness in upright species and the marsupial brain in future investigations. Such studies can offer important data about neuropsychiatric conditions such as autism and schizophrenia by linking handedness which such disorders.
In the past Malashichev discovered that certain species of walking frogs seem to have handedness, whereas jumping frogs were less likely to display such traits. And even marsupials which walk on all four legs have showed signs of handedness. Such species include sugar gliders and short-tailed opossums. However this is the first study which has analyzed bipedal kangaroo species.
Image Source: Cooberrie Park