How apes transformed from grunting beasts to humans who would go on to build skyscrapers, airplanes and advanced computers is one of the greatest questions of science. Now, a new research study might rewrite prevailing narratives about how all that happened.
According to the University of Minnesota, for a long time, the story of human evolution surrounded how a densely forested Africa slowly became drier, giving way to open grasslands that eventually caused our distant ancestors to abandon trees and start walking on two legs.
But according to a new study published in the journal Science on Thursday, the story may not be that simple. Two studies found that early apes lived in a wide variety of habitats. This includes scrublands and woody grasslands that existed 10 million years earlier than previously known.
This suggests that the modern ape anatomy could have evolved among leaf-eating apes in open woodlands instead of fruit-eating apes in forests. This research has led to a new framework for future studies on how apes evolved.
During the ten-year-long study, the researchers conducted palaeontological and geological fieldwork across nine complex fossil sites. They collected thousands of fossil plants and animal remains to reconstruct ancient habitats.
A part of the research focused on C4 plants, which are found in tropical savannahs today. Previously, they were thought to have been dominant only 10 million years ago. But the study revealed that these grasses were already an important part of the ecosystem more than 21 million years ago.
This indicated that open grasslands and scrubs existed much earlier than was previously thought.
According to The Timesthe results of the research suggested that a very early ape, called the Morotopithecus, did not live in a dense jungle as previously thought. But rather, they lived in a more open grassy landscape that was scattered with woodland areas.
Morotopithecus had an upright stance but probably did not walk on two legs like humans do. It would have scampered on the floor like a monkey instead.
“The femur and lower back anatomy of this ape reveals that it climbed trees the way modern apes do, and this is the earliest evidence for this adaptation by at least seven million years,” said James Rossie, co-author of the paper, in a press statement.
Rossie is an Associate Professor in the Department of Anthropology in the College of Arts and Sciences at Stony Brook University. According to Rossie, Morotopithecus has dental traits that show that they subsisted on fruits instead of grass.
“Morotopithecus is regarded as one of the best representatives of the ancestors to all of the living apes and humans,” said Kieran McNulty, one of the co-authors of the study in Science, to The Times.
According to McNulty, scientists have assumed that the upright postures evolved in “closed-canopy forests,” where the branches of the trees touch the branches of other trees. The assumption was also that these apes would not necessarily come down to the ground.
The new research shows that some of these apes, including Morotopithecus, lived in much more open spaces. There would have been trees around but they would have to get down from one tree to get to another.
This research can be expanded to create a new framework for studying how environmental changes in Africa and the evolution of apes, who eventually became humans, went hand in hand.