A UA anthropology professor was involved in identifying the fossilized bones of a new species discovered in Johannesburg two years ago.
A paleoanthropologist at the University of the Witwatersrand in Johannesburg asked Lucas Delezene, an assistant professor at the UofA, to assist in the study of the bones known as Homo naledi. He examined cusps on the teeth and compared them to teeth from other human ancestors.
Teeth do not wear out as easily as bones, which leaves them better preserved, Delezene said.
“It’s like having rocks in your mouth,” Delezene said.
Though most of the cusps were easily visible, Delezene said he used a 3D X-ray to create a computer model of the jaws to take a closer look at the roots of the teeth.
The cusps on the teeth did not match any other evolutionary ancestor, such as Homo neanderthalensisor Australopithecus afarensis, also known as “Lucy.” Other features, such as the tiny brain, a primitive pelvis and curved fingers, make Homo naledi unique, Delezene said.
“So it’s really a combination of these features that make Homo naledi something we’ve never seen before,” Delezene said.
Most fossilized bones are found in caves where predators captured and ate their prey. Normally, such caves have no opening to the surface, but one might develop as the rock ceiling erodes.
Bones would be discarded haphazardly in caves as predators ate their prey near the opening. From there, the bones would fossilize as dirt and sediment and be swept into the cave, Delezene said.
However, the bones of Homo naledi were found in a chamber deep underground where few animals could reach. Scientists found no bite marks.
Also, many of the bones were found in an anatomical position relative to each other. This can only happen if the bones are complete, Delezene said.
That evidence suggests that the bones, which remain undated, were actually placed in the cave before decomposition, Delezene said. That suggests that Homo naledipracticed some ritual burial and that early humans developed symbolic thought earlier than originally believed.
Some UA students expressed interest in the discovery.
Freshman Elizabeth Park said that this might be proof that Homo naledihad some kind of culture.
“They had a sense of an afterlife,” Park said. “They had spiritual beliefs. They had a drive to at least attempt to record their histories as best they could. I think they were probably far more advanced than we realize.”
Peter Ungar, chair of the Department of Anthropology at the UofA, said that having a UA professor work on the new species is a testament to the program. In addition, it brings the UofA well-deserved recognition on the international stage, he said.
“As one of my former students wrote on Facebook, ‘Represent!’” Ungar said.
The chance to work on the bones and decipher their mystery was thrilling, Delezene said.
“This is a dream come true to get a bunch of bones and figure out what they are,” he said.