3.2 The Age of Exploration
What do we know about this new hominin species Homo naledi?
- As of September 2015, more than 1550 individual fossils, from at least fifteen individuals, were recovered from the Dinaledi chamber in Rising Star cave. In the two years between their discovery and Sept. 2015, Lee Berger concluded that all fossils belonged to the same extinct hominin species, which he named Homo naledi, or “star man.”
- Homo naledi has traits similar to Australopithecus as well as traits known to be in the Homo genus. Its pelvis and legs suggest Homo naledi was bipedal, while its long fingers were useful in traveling through the trees.
- The braincase of the male skull of H. naledi measures about 560 cubic centimeters—less than half the size of the modern human skull.
- H. naledi is an animal on the cusp of transition from Australopithecus to Homo, unlike any previously discovered extinct hominin species.
When did H. naledi exist?
- The fossils have still not been dated successfully, but there is much debate as to their age. Depending on how old H. naledi is, there are significantly different implications.
- If H. naledi is less than a million years old, it is more like a recent cousin of humans, sharing the African landscape with our ancestors much more recent than previously thought.
- However, if H. naledi is extremely old, between three and four million years old, it could change how we currently view our evolutionary lineage. Ancestors like “Lucy” (A. afarensis) might not fit in the evolutionary timeline as previously thought.
The anatomy of H. naledi suggests it is most likely between 2.5 and 2.8 million years old, originating at or near the start of the Homo genus.
How did H. naledi get to the Dinaledi chamber?
- Perhaps this was the biggest question in the discovery of H. naledi. How could such a primitive creature wander into such a remote chamber?
- One theory was that a group of H. naledi became trapped in the chamber all at once—but geological evidence showed that these bones had been deposited over the course of many years, perhaps even centuries.
- If a predator of H. naledi had dragged the remains into this cave, paleoanthropologists would have seen markings on the fossilized bones, which they did not find. And if water flowing had taken these bones into the chamber, it would have also taken stones and other debris—but nothing of the sort was found in the Dinaledi chamber.
- The current theory, having exhausted all other possibilities, is that H. naledi deliberately disposed the remains of their dead in this chamber. This is a remarkable feat for such a primitive species, and completely changes our understanding of how human ancestors treated their dead in ritualistic manners.
There are still many discoveries to be made.
- Not long ago, well-respected paleoanthropologists believed South African discoveries had been depleted.
- A spark of inspiration led Lee Berger’s team to multiple incredible discoveries, located in some of the most explored regions in the history of the scientific discipline.
- If not for the ingenuity, collaboration, and perspiration of dedicated explorers, these fossils may still have been yet undiscovered, falling victim to the so-called “backyard syndrome.”
- New discoveries are out there waiting to be made in all fields of science, and it’s up to the young scientists to explore and unearth them.