Ancient human ancestors had Neanderthal ears

"Evolution was very much mosaic," said Erik Trinkaus.
By Brooks Hays   |   July 8, 2014 at 3:00 PM  |  Updated July 8, 2014 at 3:02 PM   |   Comments

ST. LOUIS, July 8 (UPI) -- Four ancient skulls unearthed in different parts of China have further muddied the already confusing story of human evolution. Researchers believe the skulls belonged to archaic humans, one of the different lineages that preceded and even lived alongside modern man.

The only problem is one of the skull specimens, about 100,000 years old, features the inner ear structure of Neanderthals, which lived in Eurasia from 200,000 to 30,000 years ago. The inner ear is the "labyrinth" within the skull's temporal bone; it houses the mechanisms that convert sound waves into electrical signals a brain can understand and help humans keep their balance.

"We fully expected the scan to reveal a temporal labyrinth that looked much like a modern human one, but what we saw was clearly typical of a Neanderthal," explained study co-author Erik Trinkaus, an anthropologist at Washington University in St. Louis.

Neanderthals and other lineages of ancient humans are all grouped under the genus Homo, but various populations of modern man's relatives each had distinct characteristics.

This latest confusing discovery is further evidence that the lines separating one group (like the Neanderthals of Eurasia) from another (like the archaic humans of ancient China) remain exceptionally blurry.

"Evolution was very much mosaic," Trinkaus said. "To the extent that this might indicate population contact, it emphasizes that human populations were very dynamic on this landscape."

In the new study, published this week in the Proceedings of the National Academy of Sciences, Trinkaus and his colleagues argue that the mixing and matching of various genetic traits is proof that different groups of modern humans routinely interbred.

"What these findings say to me are that characteristics were probably more varied in ancient human populations than we think," Trinkaus added. "The idea of distinct, separate lineages in this time period in human evolution is meaningless -- it was much more of a labyrinth than that."

© 2014 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.
Featured UPI Collection
Celebrity Couples of 2014 [PHOTOS]

Celebrity Couples of 2014 [PHOTOS]

Most Popular
You've got mites on your face, and so does everyone else
Southwest U.S. could face 35-year 'megadrought'
Volcano erupts, Iceland issues then rescinds red alert
Latvia boasts world's first net for migrating bats
Type Ia supernovas: the zombies of the cosmos
Trending News