CNN
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Human ability to walk standing on two legs According to scientists who study wildlife, it may have evolved in trees rather than on land chimpanzees In Tanzania.
This contradicts the widely accepted theory that prehistoric human relatives evolved to walk on two legs because they lived in an open savannah environment, according to a study published in the journal Wednesday. Advances in science.
Researchers from University College London (UCL) spent 15 months studying the behavior of 13 wild adult chimpanzees in the Issa Valley, which is home to a mix of dry open land and dense forest in western Tanzania. Known as the “savanna mosaic,” this environment is similar to that of our first human ancestors.
The team recorded each time the chimpanzees were upright and whether it was on the ground or in trees.
Then they compared it with standing on two legs Studies of chimpanzees living in densely forested areas elsewhere in Africa have found that Isa Valley chimpanzees spend as much time in trees as their forest-dwelling relatives.
This means they were no more land-based than current theories suggest they should have been given the more open environment they lived in. In addition, more than 85% of chimpanzees’ upright walking occurred in trees rather than on the ground.
Alex Piel, associate professor of anthropology at UCL and co-author of the study, told CNN that the prevailing theories are based on some logic.
“A long-held assumption is that fewer trees mean more time on the ground, and more time on the ground means more time upright,” Piel said.
However, his team’s data do not support this, instead suggesting that more open environments are not a catalyst for promoting bipedalism, Piel said. “That’s not a nice logical story,” I said.
The next question for the researchers is why Jesus Valley chimpanzees spend more time in trees, Piel said, even though they spend less time around trees than other chimpanzee communities.
One explanation could be that food-producing trees encourage them to spend time there to eat, but there could also be a seasonal component.
During the rainy season, the grass in Issa Valley grows to about 6.5 feet tall, Piel said, making chimpanzees more vulnerable to predators like leopards if they spend time on the ground.
“There could be a dramatic seasonal signature to this,” he said.
According to Piel, early human ancestors would have faced predation in a similar environment.
“It’s really an analog system,” I said.
However, Piel emphasized that the study is not a direct comparison between chimpanzees and our early human ancestors, but rather offers theories that should be tested against the fossil record to see what it tells us about the anatomy of early hominids.
