Homo naledi: The human ancestor fascinating anthropology

10 Sep 2015

A reconstruction of a head of a Homo naledi put together by paleoartist John Gurche. Image via Mark Thiessen/National Geographic

The very fabric of human history may have been altered completely by accident after two explorers stumbled across a collection of fossils belonging to a totally new ancestor of man and descendant of the homo genus, Homo naledi.

Two cave explorers charting the underground caverns of South Africa back in 2013 stumbled across the new species of homo sapien that had remained undiscovered after finding a collection of bones that later turned out to be a mass grave.

Dubbed the Dinaledi Chamber, the cave is now home to one of the biggest breakthroughs in anthropology in some years with the research team analysing 1,550 bone fragments for analysis before making their conclusions.

According to Popular Science, the new species has been called H. naledi due to its discovery in the Rising Star Cave system with naledi translating to star in the local Sesotho language.

Homo naledi head

A size comparison between a human head and the head of a Homo naledi. Image via Lee Berger and Peter Schmid, Wits; John Hawks, University of Wisconsin-Madison/National Geographic

The team from the University of Witwatersrand in South Africa, National Geographic and the South African Department of Science and Technology said that the fact that all bones discovered in the grave came from the same species suggests the Dinaledi Chamber was a mass grave with bodies deposited over time.

As for where the species exists on the human developmental timeline, the researchers said that Homo naledi is somewhat different to us, placing their existence during the diversification of the homo genus between 2.5m-2.8m years ago.

Homo naledi hands

The curved hands of the Homo naledi. Image via Lee Berger, Wits, photographed at Evolutionary Studies

How Homo naledi lived

With an average height of 5ft and typically weighing 45kg, the H. naledi species had smaller brains than us, having traits from both the homo genus and other variant of extinct hominid, the Australopith.

Its hands revealed much about how H. naledi would have lived as, while its hand resembles a modern human’s, one curved finger and a lower arch suggest it spent much of its time climbing trees.

In their paper published on eLife, the researchers said that the discovery of H. naledi poses further challenges to the established evolution model of humans.

Anthropologists have believed until now that our brains grew in size as we learned to use tools, eat a better diet and our teeth became smaller.

However, despite H. naledi’s small brain, it has small teeth and hands capable of using tools, which the researchers said poses the possibility that evolution doesn’t occur as a singular step.

Led by anthropologist Lee Berger, the research team said that there is still much to discover about the species, but before any assumptions are made a more exact date of its origin will need to be clarified.

Updated 5.04pm, 14/09/2015: The headline of this article was changed to reflect that while Homo Naledi is a descendant of the homo genus it is an ancestor of modern humans

Colm Gorey was a senior journalist with Silicon Republic