August 3, 2009

Big Haul: A thousand treasures

Professor of Paleoanthropology at Lehman College and Research Associate in Paleontology at the American Museum of Natural History

NAIROBI, Kenya | We’ve made our way back to the capital from Lake Victoria. Most of us struck camp on the 31st of July, but one team stayed back an extra day. There was that much to do. Co-director Holly Dunsworth and I even managed to score a flight back to Nairobi with a local bush pilot. Apart from being a lot of fun, it was a relief: We were seriously concerned about space in the vehicles with all the fossils and samples we were bringing back.

Of course, as problems go, that’s a good one to have. The season has been a resounding success. We did all the things we set out to do and collected a vast number of fossils–more than a thousand identifiable specimens at last count. Now the real work begins!

Back in town, we took a well-earned day off and went to the nearby national park. We saw spectacular wildlife, including lions, rhinos, hippos and even the shy and elusive serval. Then it was back to work. Apart from the tedium of cleaning and inventorying all our equipment, we started in earnest to catalogue all our finds. This is a lengthy and very important process. Beautiful as they are, the fossils are no real use without being properly identified. We compare all the finds to remains of known species from similar time periods, both from Rusinga but also farther afield. It’s not always easy, especially in cases where reference species are represented by very meager remains. And if we think we have a new species, we must of course work very carefully to be sure. Some of our finds are often broken, or encased in surrounding rock, called matrix. In these cases the fossils need to cleaned and conserved before we can work on them. Fortunately, the National Museums on Kenya (where the fossils are housed) has an outstanding team, so all the work can be done there. If all goes well, they’ll turn what are now just glimpses of fossil into beautiful new specimens for us to work on.

While some specimens need work, others emerged in superb condition, stunning from the moment we laid eyes upon them. On one morning alone at the Waregi site, we found five intact skulls. Although not fully cleaned yet, we know that they belong to long-extinct rodent species, as well as the much rarer elephant shrew. We have fossilised hedgehog remains, rabbits, birds and lizards, to name but a few.

At the last site we were at, Kiahera, we found a number of Proconsul teeth and foot bones. Those are being worked on right now. We also found the arm bone of an animal that had clearly been chewed by a predator 18 million years ago. You can still see the bite marks! As I said before, the thing that makes Rusinga so special is the sheer diversity of remains we find – everything from mammals, to birds, to reptiles to insects and plants. A few days before we left I even found two exquisite fish preserved in a piece of shale. Finding such creatures is not only interesting in its own right, but it also helps clarify the ecological context that Proconsul and other early apes thrived in.

And we had a lot of fun. There were anywhere from 17 to 25 of in camp at various times, representing five different nations. We had two birthdays, some very late nights and quite a few soccer games on the nearby airstrip. We also cemented good friendships and associations with many of the local people we hired. Providing local employment is one of the best ways one can give something back in such a poor region of the country. It also helps explain why we are there. Rusinga is world famous in the world of human and ape origins, but that is not well understood at the local level. It’s understandable given the harsh realities of life on the island (40% of people are HIV positive), and so every little bit counts in terms of local education and awareness.

I’ll post once more before we depart for home, and also turn the blog over to two of our CUNY grad students–Julia Zichello, who posted earlier, and Scott Blumenthal. They’re working on them now, so check back in.