Chimpanzee fingers, on the other hand, have elongated over time, allowing the animals to move better on the tree canopy. Our hands, it turns out, are more “primitive” than our hairy relatives. The researchers found that the hands of the common ancestor of chimps and humans, as well as perhaps much earlier ancestors, had just slightly longer fingers and shorter thumbs than those of modern-day men and women. The study also incorporated some of the earliest members of the human lineage, as well as extinct apes. Almécija and his colleagues began to collect and compare measurements of the thumb and finger proportions of chimpanzees, gorillas, humans and other primates in natural collections all over the world. “But no one had ever actually quantified this.”ĭr. So, it is likely to assume that their shape is more primitive, and human hands are the ones that have changed the most,” he said. “When you look at the hands of living apes, they all look superficially very similar. Almécija, this theory didn’t entirely add up. The evolution, they thought, could be explained as a specific adaptation that would allow humans to make and use stone tools.īut for Dr. Then, human hands evolved in recent evolutionary history. We have a long thumb relative to our other fingers, which allows us to easily grip and manipulate objects much better than our shorter-thumbed relatives.įor decades, the primary school of thought among scientists was that humans’ and chimps’ common ancestor looked almost identical to a chimpanzee, including chimp-like hands. However, despite sharing 96 percent of our genes with our ape relatives, human and chimp hands vary greatly. New molecular tools in the 1980s provided DNA evidence that both chimpanzees and humans derived from a common ancestor some 7 million years ago. “But as we began finding older and older ancestors of humans, their hand proportions looked very much like a modern-day human’s.” “It’s a widely accepted paradigm that the ancestor of humans had a hand like a chimpanzee, with long fingers and short thumbs that were not as proficient at handling things,” said Sergio Almécija, an assistant professor at the Center for the Advanced Study of Human Paleobiology who led the study. They also challenge the belief that the human hand evolved as a result of pressures from natural selection to become better toolmakers. The findings, published in Nature Communications, reverse assumptions about what the common ancestor of humans and chimpanzees may have looked like. The chimpanzee hand, by contrast, once resembled something akin to a human’s and evolved into something quite different. After all, our hands are elegant tools, capable of precisely gripping a tiny needle, strumming a guitar or buttoning a shirt.īut a new study from a George Washington University professor suggests just the opposite: Human hand proportions have not changed very much since the human and chimp lineages last shared a common ancestor around 7 million years ago. For additional information visit Linking to and Using Content from MedlinePlus.Many researchers have long speculated that the human hand evolved significantly over time-from ape-like to adept, modern-day appendages. Any duplication or distribution of the information contained herein is strictly prohibited without authorization. Links to other sites are provided for information only - they do not constitute endorsements of those other sites. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. This site complies with the HONcode standard for trustworthy health information: verify here. Learn more about A.D.A.M.'s editorial policy editorial process and privacy policy. is among the first to achieve this important distinction for online health information and services. follows rigorous standards of quality and accountability. is accredited by URAC, for Health Content Provider (URAC's accreditation program is an independent audit to verify that A.D.A.M.
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