World / Science & Health

Oldest known upright ape found in Germany

AP, Reuters

The remains of an ancient ape found in a Bavarian clay pit suggest that humans’ ancestors began standing upright millions of years earlier than previously thought, scientists said Wednesday.

An international team of researchers says the fossilized partial skeleton of a male ape that lived almost 12 million years ago in the humid forests of what is now southern Germany bears a striking resemblance to modern human bones. In a paper published by the journal Nature, they concluded that the previously unknown species — named Danuvius guggenmosi — could walk on two legs but also climb like an ape.

The findings “raise fundamental questions about our previous understanding of the evolution of the great apes and humans,” said Madelaine Boehme of the University of Tuebingen, Germany, who led the research.

The question of when apes evolved bipedal motion has fascinated scientists since Charles Darwin first argued that they were the ancestors of humans.

The discovery suggests that bipedalism originated in a common ancestor of humans and the great apes — a group that includes chimpanzees, bonobos, gorillas and orangutans — that inhabited Europe rather than an ancestor from Africa, the continent where our species first appeared roughly 300,000 years ago, the researchers said.

Until now, the oldest fossil evidence of bipedalism in humankind’s evolutionary tree dated to about 6 million years ago: fossils from Kenya of an extinct member of the human lineage called Orrorin tugenensis, and footprints on the Mediterranean island of Crete.

If Danuvius turns out to be ancestral to humans, that would mean that some of its descendants at some point made their way to Africa.

“This changes our view of early human evolution, which is that it all happened in Africa,” Boehme said in an interview.

The discovery may also shatter the prevailing notion of how bipedalism evolved: that a chimpanzee-like ancestor started to walk on two legs after environmental changes created open landscapes and savannas where forests once dominated.

“This paradigm is now declining — or, in other words, is shown by us to be wrong,” Boehme said.

Danuvius indicates that upright walking originated in the trees, not on the ground, and that humankind’s last common ancestor with apes did not go through a stage of hunched knuckle-walking, as previously thought, Boehme added.

“Our last common ancestor with great apes doesn’t look like a chimp, or any living great ape. He may have looked like Danuvius,” Boehme said.

Boehme, along with researchers from Bulgaria, Germany, Canada and the United States, examined more than 15,000 bones recovered from a trove of archaeological remains known as the Hammerschmiede (Hammer Smithy) about 70 kilometers (45 miles) west of Munich.

Among the remains they were able to piece together were primate fossils belonging to four individuals that lived 11.62 million years ago. The most complete, an adult male, likely stood about 1 meter (3 feet, 4 inches) tall, weighed 31 kilograms (68 pounds) and looked similar to modern-day bonobos, a species of chimpanzee.

“It was astonishing for us to realize how similar certain bones are to humans, as opposed to great apes,” Boehme said.

Thanks to several well-preserved vertebra and limb, finger and toe bones, the scientists were able to reconstruct how Danuvius moved, concluding that while it would have been able to hang from branches by its arms, it could also straighten its legs to walk upright.

Like humans, Danuvius had an S-shaped spine to hold its body upright while standing. Unlike humans, it had a powerful, opposable big toe that would have allowed it to grab branches with its foot and safely walk through the treetops.

Fred Spoor, a paleontologist at the Natural History Museum in London, called the fossil finds “fantastic” but said they would likely be the subject of much debate — not least because they could challenge many existing ideas about evolution.

“I can see that there will be a lot of agonizing and re-analysis of what these fossils mean,” said Spoor, who wasn’t involved in the study.

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