One leading theory for the benefits of handedness in an individual organism stems from its connection to brain asymmetry, and the division of labor between the two halves of the brain. “We’re in no man’s land a little bit,” Hopkins admits. Related Article The Hidden Beauty Of The Human Placenta Now that we have examples of non-human handedness, the next question is, why do animals take sides? In other words, as Hopkins puts it, “what’s the underlying evolutionary mechanism that’s selective for this?” Researchers are still theorizing. On the other hand (ahem), about 66 percent of orangutans are lefties. Hopkins offers some examples from his own research: In chimpanzee populations, about 65-70 percent are right-handed. But only recently have they started to learn that, like Homo sapiens, other species can be characteristically handed-meaning that “a statistically significant majority of the individuals in a population prefer one hand to the other,” says Bill Hopkins, who studies lateralization and handedness in primates at Georgia State University. Researchers have known for decades that other animals demonstrate handedness. “You see asymmetry going all the way down to fish,” says Claudio Cantalupo, who studies handedness and brain asymmetry in humans and nonhuman primates at Clemson University. Learn the art of a great handshake and shake hands with confidence with these three tips.Related Segment Jane Goodall On The Future Of Evolutionary Scienceīrain asymmetry was once considered unique to humans, but now we know that it’s common in vertebrates. The human hands may represent a very primitive anatomical structure that has been around for millions of years.ĭon’t let a friendly handshake turn into an awkward experience. Based on their findings, they concluded that the ancient ancestor of humans and chimpanzees had more human like hands. During the study, they sampled humans, apes and monkeys, as well as some extinct species such as Proconsul heseloni, Ardipithecus ramidus and Australopithecus sediba. Researchers have since measured the proportions of both human and chimp hands to see which is closer to our hands. Early hominins that had nothing to do with making tools still appear to have hands similar to those of modern humans. But now with a growing body of evidence, human hands have in fact stayed close to being the same for millions of year. This makes it ideal for them to swing in trees but aren’t as handy with grasping objects.įor many years the prevailing view among researchers was that humans had chimplike hands and that our hands changed in response to the pressures of natural selection to make us better toolmakers. With chimpanzees it’s the opposite-they have much longer fingers and shorter thumbs. Humans have a fairly long thumb and shorter fingers allowing us to touch our thumbs to any point along our fingers to therefore easily grasp objects.
In a study done by the journal of Nature Communications, they found that although the human hand proportions have changed some from the last common ancestor of chimps and humans, the hands of chimpanzees and orangutans have evolved substantially. Here are 18 fascinating facts about one super impressive body part: the human hands.
A new study suggests that there are some aspects of the human hand that are anatomically primitive-even more so than our closest ancestors: the chimpanzee.
Scientists have assumed that our hands evolved their uniqueness over millions of years. Human hands can build amazing structures, play the keys of a piano, and paint works of art that stand the test of time.
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