Are Wallabies Left or Right Handed? Both! (Sometimes)January 27, 2012, 9:30 am by Scientific American: Mind and BrainWhich limb do you prefer? If you’re like most members of our species, you prefer your right hand for most tasks. If you’re like a smaller minority of our species, you might prefer your left hand. Very, very few of us are truly ambidextrous. Most of us have at least a minor preference for one hand over the other. So do wallabies.On the one hand (ha!), this shouldn’t be all that surprising. Nervous systems became lateralized quite early in the evolution of vertebrates. For example, there is research showing that fish show a preference for touching the sides of aquariums with one side of their ventral fins or another. And it is not surprising that humans overwhelmingly favor their right hands. When it comes to feeding behaviors, fishes, reptiles, and toads all favor their right eye (and their brain’s left hemisphere). The same is true for birds like chickens, pigeons, quails, and stilts. The right-eye preference can be so strong that one bird – New Zealand wry-billed plover – evolved a beak that slopes slightly to the right. And a study of seventy-five whales showed that sixty of them had abrasions on the right side of their jaws, while the other fifteen had only injured the left side of their jaws. As Peter F. MacNeilage, Lesley J. Rogers and Giorgio Vallortigara pointed out in a 2009 article in Scientific American , the data indicated that whales tended to use one side of the jaw more than the other for gathering food, “and that ‘right-jawedness’ is by far the norm.” [More]
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