Reviewing the September excavation in the Rising Star cave system

2 minute read

In September, the team was underground in the Rising Star cave system, working at new excavations in the Lesedi Chamber and Dinaledi Chamber. I posted updates on the excavation goals and the progress at the end of the month on Medium, and I thought it would be helpful to provide links to those articles here.

A look at some photos of the live National Geographic Classroom events in the Rising Star cave system
A look at some photos of the live National Geographic Classroom events in the Rising Star cave system

In the first week, I reviewed the hypotheses that we set out to test: “Renewed excavations in the Rising Star cave”. Key among them is the formation of the fossil assemblage within the Dinaledi Chamber.

Many people have been curious whether some other entrance to this chamber may have existed in the past. So far, geological work in the chamber has found no other passage that might have allowed hominins or their bodies to get in. There’s a lot of evidence that the chamber must have been very inaccessible when the remains of H. naledi arrived — especially the clear difference in sediment composition between Dinaledi and other nearby chambers, and the lack of evidence for any other medium or large animal remains. It appears that the hominin remains must have entered the chamber in the same way we do today, down this Chute.
But nearly all of the hominin remains so far come from a tiny area of excavation, only 0.8 square meters, at the far end of the chamber more than 10 meters from the Chute.

Later, near the end of the excavation work, I reviewed some of the discoveries the team made: “What we’ve learned from the Rising Star cave system this month”. Perhaps the most interesting is a feature just beneath the base of the Chute:

This mass of bone has emerged just at the base of the Chute, the narrow entry channel into which the team enters the chamber. After weeks of careful excavation, the team can now see part of an articulated hand, ribs and a possible shoulder, even some teeth in what appears to be proper anatomical order.
This may be the partial skeleton of a single hominin individual. We do not know how much additional bone may yet remain just beneath the surface.

It will be some time before we know fully the results of the September excavation. We will need to consolidate the feature at the base of the Chute and extract it to the laboratory for further preparation. We will also need to get chemical and biological results back from samples taken inside both chambers. We have a lot of work ahead of us, and we’ll update as we can.