Rare 10m-year-old fossil discovery potentially rewrites human evolution

18 Sep 2019

Illustration of what Rudapithecus may have looked like. Image: John Siddick

The discovery of a fossilised ape bone rarely preserved by time has been unearthed in Hungary, offering new insight into human evolution.

Near the old mining town of Rudabánya in Hungary, palaeontologists have uncovered the remains of potentially a very important creature in the human family tree. Writing in the Journal of Human Evolution, an international research team led by the University of Missouri’s Carol Ward revealed the discovery of a 10m-year-old fossilised ape dubbed Rudapithecus.

What makes the find particularly important was the yielding of a pelvis, which is among the most informative bones of a skeleton and one of the least preserved by time. After analysing the pelvis, the team discovered that it shows human bipedalism may have deeper ancestral origins than we once thought.

The bone was originally discovered by David Begun of the University of Toronto, whose research so far has shown Rudapithecus was a relative of modern African apes and humans, making its place in Europe rather surprising. Ward said Rudapithecus would have acted like many modern apes, climbing with its arms from branch to branch and its body upright.

Dog-sized ape

“However, it would have differed from modern great apes by having a more flexible lower back, which would mean when Rudapithecus came down to the ground, it might have had the ability to stand upright more like humans do,” Ward added.

“This evidence supports the idea that rather than asking why human ancestors stood up from all fours, perhaps we should be asking why our ancestors never dropped down on all fours in the first place.”

One of the reasons that modern African apes walk on all fours is because they have a long pelvis and short lower back due to their size. If humans evolved from an African ape-like body build, Ward said, substantial changes to lengthen the lower back and shorten the pelvis would have been required.

However, the transition from Rudapithecus would have been a lot more straightforward.

“We were able to determine that Rudapithecus would have had a more flexible torso than today’s African apes because it was much smaller – only about the size of a medium dog,” Ward said. “This is significant because our finding supports the idea suggested by other evidence that human ancestors might not have been built quite like modern African apes.”

The team’s next step in the research will be to conduct a 3D analysis of other fossilised parts of the ape to get a clearer picture of how it moved.

Colm Gorey was a senior journalist with Silicon Republic