![]() There is a widely held assumption among palaeontologists that the last common ancestor (LCA) of humans and apes, an individual whose identity remains uncertain, was a prototype chimp with chimp-like hands.īut a team led by Sergio Almecija of The George Washington University's Center for the Advanced Study of Human Paleobiology, is challenging that. The human hand has a longer thumb relative to the other fingers than that of chimps and other apes - allowing for what scientists call "pad-to-pad" precision grasping, which simply means that our fingertips are able to touch. In fact, it is the hands of chimps and orangutans that changed most since they split off to form new branches of the hominid family tree - developing longer fingers, compared to the thumb, for swinging on tree branches. "These findings indicate that the structure of the modern human hand is largely primitive in nature, rather than the result of selective pressures in the context of stone tool-making," said a press summary from the journal Nature Communications, which published the study. In fact, human hands are likely more similar to those of the last common ancestor we and chimps shared millions of years ago. ![]() On Tuesday, scientists in the United States and Spain said the human hand may be more primitive than that of our closest living cousin, the chimpanzee. Strong fists for defending ourselves and opposable thumbs for work as fine as threading a needle - hand specialisation is widely believed to have given humans a major evolutionary advantage. The chimps were quite adept with this method, which offers a model for how sensitive, nimble hands might have first developed, as they may have enabled our dexterous shared ancestors to select better food faster than clumsy, fruit-smashing grips, which might have already been sufficient for moving through trees or brush otherwise.On Tuesday, scientists in the United States and Spain said the human hand may be more primitive than that of our closest living cousin, the chimpanzee. Sorting figs with sensitive fingers and thumbs was a much faster process than monkeys could hope for with their faces. This means that they not only likely end up with unripe fruit flavor in their mouths, but they’re stuck with a slower process to evaluate their food. In contrast to the monkeys, chimpanzees were observed giving figs a gentle squeeze, just as you’d do in the produce section of your grocery store. Many primates, from red colobus monkeys to chimpanzees, then have to poke and feel a fig to gauge how delicious it’s likely to be, although colobus monkeys, lacking opposable thumbs, are forced to prod with their teeth instead. ![]() Ripe fruit from Ficus sansibarica are hard to spot from looks alone, and one tree might have multiple batches of fruit growing, meaning every possible snack needs to be checked out before it’s eaten. The task the researchers focused on was picking figs. So the researchers were looking to modern primates for uses of their sophisticated hands, hoping that they’d still demonstrate some of the their uses long before we decided that phalanges were best used to poke and swipe pieces of glass and plastic. Building tools is great, and we’re fairly sure that good hands are what made tool creation possible, but that doesn’t mean that making tools was the original evolutionary pressure for our manual dexterity. Like many special abilities of homo sapiens, we might not have an exclusive claim on nimble digits, which has allowed scientists to look into how chimpanzees are making use of their fingers for clues.Ī study from Dartmouth College looked at a variety of primates to see what advantage sophisticated hands might offer. However, the tools involved in these activities did depend on our relatively sophisticated hands, which is part of why anthropologists are so keen to figure out how they got started. Our manual dexterity also didn’t arise thanks to more tactile activities, like pouring a drink, threading a needle or writing one’s name. On April 25th, 2016 we learned about Dexterous fingers and thumbs may have arisen so we could sort fruitīelieve it or not, your hands did not evolve just so you could interact with your favorite touchscreen device.
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