Do Other Primates and Animals Exhibit Dominant Handedness?
While lobsters and crabs display significant handedness in the form of a larger, more powerful claw, and other animals exhibit dexterity to varying degrees, the question remains: Do other primates and animals show the same level of handedness as humans and other primates?
General Animal Handedness
Most animals that require dexterity to perform certain tasks indeed show some form of preferred hand or paw. This phenomenon is an evolutional response to the energy-consuming nature of the brain and nervous system. Enabling some tasks to be handled with less processing power can make the difference between surviving and not surviving, reducing the odds of a leading cause of mortality in the wild - starvation.
A comprehensive scientific study on the handedness of various animals, published in the Journal of Comparative Neurology, reports that the point of diminishing return for these energy-efficient mechanisms is the allocation of "enough" processing power to fine motor control.
Primates and Handedness
primates, including apes, do exhibit preferred hands, although the handedness can vary from individual to individual and task to task. Unlike humans, which generally have a dominant hand that remains constant over time, ape handedness is more fluid.
Neanderthal Handedness
Studies of Neanderthal skeletal anatomy and hand tools suggest that Neanderthals were mostly right-handed. Evidence from these studies can be found in the Journal of Human Evolution.
Mice and Hand Preferences
One of the interesting findings comes from a study involving mice. A scientist tested mice in a plastic box with a tube in the middle. The mice were asked to reach out with one of their paws to grab a bit of maple-flavored oatmeal. Surprisingly, approximately 50% of the mice were right-pawed, while a smaller number showed ambidexterity. Some mice even used their preferred paw, regardless of the awkward positioning of the tube.
Other Animals with Paw Preferences
Interestingly, some other animals also exhibit clear paw preferences. For instance, a report suggests that eastern gray and red kangaroos favor their left paw, showcasing the intriguing diversity in hand or paw preferences across different species.
Brain Asymmetry and Handedness
Many animals exhibit brain asymmetry, which affects their responses to various situations. This asymmetry doesn’t necessarily equate to dominant handedness. Rather, certain tasks tend to be handled by one side of the brain. The handedness in humans is likely an evolutional result of this overall brain asymmetry. More detailed discussions on this topic can be found in the Frontiers in Human Neuroscience publication.
Cats and Handedness
Lastly, it's worth noting that even cats, a common household pet, may show some form of handedness. While studies do not provide a definitive answer, it is believed that cats may be right-pawed or left-pawed, with no clear preference like humans have for handedness.
Conclusion:
While primates and certain other animals exhibit handedness, the mechanisms and results differ significantly from those seen in humans. Understanding the evolution and mechanisms behind these behaviors can provide valuable insights into the neuroscience of dexterity and handedness.