Update (Nov 2013): Please be aware this article was written as a first impressions of an ongoing expedition as an outsider onlooker. I updated this information (Rising Star Update) as more data came to light a few weeks later. It now seems fairly clear that this location will become a significant one in the study of early hominids.
Update (Sept 2015): Almost 2 years later the results are being reported. I will provide a fuller overview in a future post. For now I have written about my predictions about how creationists will respond (Bones of Contention: How will Creationists respond to huge new hominid fossil find?). Below were my first impressions from 2 years ago. I look forward to comparing my first thoughts and conjectures to the data that has now been released.
An expedition to recover hominid remains is underway and you can follow the progress of that expedition in real-time thanks to social media. From Twitter (LeeRberger, johnhawks and #risingstarexpedition) and the National Geographic Explorer web page that provides videos and reporting on the expedition, we learn that Dr. Lee Berger, a professor at the University of Witwatersrand in Johannesburg South Africa, is involved in yet another astounding hominid fossil discovery. I wrote about Berger’s most famous find a year ago in my Geological Context series on human fossils (Geological Context I: The Frequently Overlooked Geological Context of Human Fossils). Apparently just a month ago cavers identified a potential hominid fossil site deep in a cave just north of Johannesburg. The site is a chamber deep in a large cave complex that has been explored by cavers in the past but this chamber (more than 100 feet below the surface) was only accessible through a long narrow crack and thus never visited before. However, a couple of persistent cavers who finally got through last month and recognized the potential significance of what they found. Lee Berger put out a call on social media to recruit some skinny cavers who could fit through an 18 cm narrows to gain access to the large chamber of interest. This is no Geraldo Rivera opening of Al Capone’s secret vault. Preliminary exploration found bones in this chamber but the conditions were very difficult and so none were retrieved at the time of their discovery. What sort of hominid these bones belonged too, now many hominids, how old are there were very much mysteries begging to be explored. In the space of just a few weeks six volunteer cavers, all women, were flown to South Africa and assembled as a team to explore this chamber. The first entry into the this chamber happened this past weekend (11/9, 11/10) and exploration and recovery of the contents of that chamber is continuing right now!
I am writing about this today because this is a chance to see science in progress. Dr. Berger, Dr. Hawks and several other anthropologists are on the site directing and observing the progress of the excavation of this chamber. Berger (#LeeRberger) and Hawks (#johnhawks) are providing updates on Twitter of the action at the site including in some cases minute by minute accounts of who is descending and returning to the surface and what they are bringing up with them. The team leaders are able to watch (see image below) the action from the surface and direct the cavers as they excavate the many bones that they are finding. Welcome to the modern era of scientific exploration!
Follow the expedition:
On Twitter follow LeeRberger, johnhawks or RisingStarExped or better yet follow #risingstarexpedition for all tweets related to this fossil find. Below is a picture from inside the operations tent by a National Geographic correspondent on the scene. National Geographic news stream that includes updates and videos on the progress of the excavation team can be found at this link: http://newswatch.nationalgeographic.com/tag/rising-star-expedition/. Check out this video taken of one of the cavers squeezing through the “postbox” on their way to the chamber. Lee Berger calls this one of the “easier” squeezes on the way to the chamber. I can’t imagine what a hard one is! Don’t watch if you are claustrophobic! http://youtu.be/NvqO77mA6hg
How Science Works: Contrasting Hominid Research Projects
A few weeks ago I wrote about the geological context of the hominid skulls found at a site near Dmanisi Georgia (the country) (Geological Context III: The Origins of the Dmanisi Skull). In that post I noted that the Dmanisi skull #5 was first observed in 2005 but that the description and discussion of that skull was only just published a bit over a month ago; a full 8 years after its discovery. The Dmanisi team published results about other partial skulls (crania) found at the same site, all the while knowing they knew they had a better skull. I don’t really have a problem with this as I explained in that post. These crania and skulls were found in rock matrix and take a large amount of prep work. Political battles with local governments and individuals are also possible causes for delay but I am unaware of any in this particular case. It should be noted as well that the researchers knew that what these crania represented would be highly debated in the anthropology community and thus they had to be as careful as they could be to get their data right and to have vetted their interpretations thoroughly before publishing.
Compare this with the approach of Lee Berger’s team. Only a bit over a month after its initial discovery they are sharing the progress of their work with the world at the same time they are able to physically examine these fossils for the very first time. In the past, a site such as this might have remained under wraps for years until enough data could be collected to make a huge splash in journals like Nature and Science. For bystanders, such as myself, the more open approach of the South African group is refreshing. I very much appreciate their willingness to share this moment with the rest of the world. They are allowing us to see science in progress rather than just the end product.
Of course Berger’s team is not sharing everything they find, nor would I expect them too. Graduate student careers, future funding, and accurate analysis of the data all require that many details be held back before they can be shared with the wider community in a systematic fashion. Despite the potential importance of the data and the implication for all those involved what they have revealed is not insignificant. Expedition leader’s tweets over the past three days have revealed that they have already recovered more than 100 hominid bones (update 11/17 now approaching 300 total bones and bones fragments, a complete human would be 206 bones) representing more than one individual. We know that these are bones that they have been able to pick off or extract from the top sediments of the chamber floor. We also know that they have found bones in a “side” chamber. Of course in our instant-gratification culture we are never satisfied with what we know but always want to know more. I think the group has done an excellent job at finding a balance between allowing people to feel like they are part of a potentially significant discovery while at the same time not jumping the gun on divulging results before the fossils have been properly processed.
So why all the excitement? What is the big mystery here?
You might be asking, why all the fuss about a few bones lying around in a cave? If you are, chances are you aren’t familiar with other fossil hominids in the same genera region of South Africa (see my post: Geological Context I: The Frequently Overlooked Geological Context of Human Fossils). There is every expectation that these fossils are not just the remains of a couple of kids or misguided cavers who wandered into a cave and fell into this chamber (apparently it is a long drop to the bottom of this chamber). Clearly the group assembled doesn’t believe that these are remains of modern humans and images (from a distance) that have been made public of the bones suggest they are very old. So whose bones are they and how did they get there? Are they the remains of some ancient people who were unfortunate and fell into the cave via some accident? Did this happen thousands, tens or hundreds of thousands or even millions of years ago? Although no one was there to witness their demise, these bones will eventually tell a story. Already the presence of multiple individuals and apparently at least one in a side chamber suggest that this was something more than a single chance accident to one individual, but more than that we cannot say right now.
How will researchers be able to tell the story of the bones? Science enables us to reconstruct the past whether it be the very recent or the very ancient. Obviously there are greater challenges in reconstructing very old events, but careful observations of the geological context, multiple forms of dating the soil and possibly the bones themselves, the organization of the bones on the ground (for example: are they pulled apart as if by a carnivore, laid out in death position from a fall (their being in side chambers suggesting they moved around rather than fell instantly to their deaths) all will combine to tell a story. I expect that the expedition team thinks and probably hopes that these bones represent an ancient hominid lineage rather than a modern humans but the bones not matter what the investigators may hope they have found. By now they almost certainly have a clue if the bones are related to the Australopithecus fossils from other parts of South Africa since there are distinctive features in several bones and their brains are 50% the size of modern humans. None of the team is speaking publicly about these specifics yet and again I would emphasize that such information, even if it were known, would not be expected to be revealed right away.
Solid science involves well-tested hypotheses that involve painstaking attention to detail, collection of many sources of data, vetting ideas among colleagues and so forth. It may be tempting to speculate about the significance of these fossils and jump to conclusions but this team and others such as the one studying the Dmanisi site can be expected, and should, take a conservative approach to their publications and press releases, checking and re-checking their data before making their conclusions public. Berger’s team has taken a more open approach to the initial discovery but the details and explanations they derive to explain these fossils will still likely be laid out in manuscripts stretching over the next decade. The context of this find suggests that it is almost certain to be a fascinating story. We will have to wait and see but for now at least we are being treated to the knowledge that there is a really interesting mystery unfolding that we will get to read about over the coming years.
Full disclosure: I have no personal connection to this research. Please be aware that I write the above as one that is outside of the anthropology community and has no especial expertise in this area although I do maintain an active readership of research literature. I am a fascinated bystander and want to thank Berger, Hawks and others for their willingness to let us share in a bit of the fun of the hunt.