Fieldwork is glamorous. Well, at least in the sense of discovering things first-hand; not usually in the sense of glamourous living conditions! However, paleontologists and archaeologists often make exciting discoveries in museum collections too. My name is Briana Pobiner, and I’m a prehistoric archaeologist in the Human Origins Program in the Department of Anthropology at the Smithsonian’s National Museum of Natural History. I just returned from Kenya, studying fossils in the Paleontology Division of the Nairobi National Museum excavated from the Smithsonian-National Museums of Kenya prehistoric research site of Olorgesailie.
The Smithsonian excavations at Olorgesailie have taken place over nearly the past 3 decades, so part of what I get to do is open bags with fossils in them that have not been opened since the day the fossil was excavated in, say, 1988 – when I was 13 years old!
My main research focus is on prehistoric human diet, so I’m examining the animal fossils for evidence of human butchery in the form of marks left by stone knives. But part of the overall research at Olorgesailie is trying to understand how early human behavior – including animal butchery, plant processing, and stone toolmaking – varied over a larger landscape. To do this, the team excavated many sites in a single time horizon – in this case, that horizon is 990,000 years old. Part of reconstructing what that landscape looked like involves identifying the species of animals found in the excavations. I have been studying these fossils since 2004, and according to my Excel database, I have already studied 56,856 fossils before this year’s research commenced!
Every bone is important in these kinds of analyses. Out of the dozens of thousands of animal bones from the 990,000 year old layers of sediments at Olorgesailie, we have only identified one giraffe tooth.
This is really interesting because most of the fossil animals from this layer are grazers (they eat grass) – like zebras, white rhinos, and certain species of antelope – implying that there was a lot of open grasslands around Olorgesailie at this time. But giraffes are browsers; they eat leaves from trees. So this single giraffe tooth tells us that there were also trees in the general vicinity of Olorgesailie. You can see Dr. Rick Potts, the director of the Human Origins Program at the Smithsonian and of the Olorgesailie research project, and I were very happy to confirm that this tooth is indeed from a giraffe by comparing it to a modern giraffe tooth in the Osteology Division at the museum.
Images and text by Dr. Briana Pobiner, prehistoric archaeologist in the Human Origins Program, Smithsonian’s National Museum of Natural History