June 28, 2011
Late yesterday afternoon, Kathryn Ranhorn made her way to our camp. Katie is an American student who’s been doing interesting work in Tanzania for the past year, and will be starting her life as a graduate student at George Washington University, in D.C., in September. For now, she’s come to Olorgesailie to participate in the excavations. And she’ll be helping me out on this season’s blog.
In yesterday’s post, I left off as we headed across the wet river to a site named BOK-2. Today, I took Katie over there, too, and we joined up with Dr. Alison Brooks, who is leading the excavation at this site. Alison, a professor of anthropology at GWU, will also be Katie’s graduate school supervisor over the next few years.
Seventeen of our excavators are helping Alison uncover the finds at BOK-2, and they’ll be hard at work over the next several weeks. I’ll explain more later about how we name sites. For now, let me tell what we’ve found out from our previous excavations at this site – and the reason why we’re going back to dig more.
The sediments at BOK-2 are the younger than the layers containing handaxes. In fact, the stone tools at BOK-2 are of a later technology, called the Middle Stone Age (MSA). BOK-2 sediments date between 493,000 and 220,000 years old, and our team is carrying out tests of the sediments to see if we can obtain a much more precise date in that time span.
Alison, who is interested in lithic technology of the MSA, began excavating this site in 2002. Since then, she and her team have discovered a type of technology not seen in the older layers at Olorgesailie. This technology is dominated by small obsidian points and retouched flakes, very different from the bulky boulders, handaxes, and hammerstones our team has been finding at Site 15. What do these differences mean? The goal at BOK-2 for this field season will be to answer just that. Specifically we will continue uncovering stone tools and bones to reconstruct a better picture of the people who lived there and the technology they used.
Around 12:30pm, the two teams working at Site 15 and BOK-2 were hungry, as it was time to head back to Kampi Safi for lunch – and out of the hot sun for a couple hours. At BOK-2, the crew trekked back to the Land Cruiser only to find yet another small challenge in this rough terrain – a flat tire. Teamwork prevailed, and the tire was replaced with a spare in no time. We had a special lunch, which the camp cooks have dubbed safari njema, which means “nice journey” in Swahili. Let’s hope safari njema will prevent future flat tires!
An intriguing discovery came in the afternoon, back at BOK-2, by Kamula, one of the crew members. Amidst the dry dusty sediment, he found a tiny crocodile tooth. What was the crocodile tooth doing there at this archeological site? Where did it come from? There could be several answers to these questions, but one thing it tells us for sure is that there must have been a permanent water source nearby. We should find more clues about the ancient habitat as the season presses on.