August 4, 2011
The day started like any other day, with breakfast at 6:45. This morning the camp cooks made us a special farewell treat – French toast! – to go with our usual piece of papaya and coffee and tea.
After breakfast, we went to our respective tents and spent the next hour packing up belongings. Within a few hours, the tents had been collapsed, neatly folded, and stowed away. Several truckloads were taken to the Site Museum, where we store some research equipment and tables. The kitchen was disassembled. Several hours passed with everyone milling about, loading trucks, cleaning, and packing.
Everyone piled into the cars and eventually began the journey back to Nairobi. And that was the end of our field camp, Kampi Safi, for this field season.
For some of us in camp, it’s hard to leave this piece of ground in the middle of the Rift Valley – its dynamic rush of clouds, bright sun every day, and the astounding clarity of stars at night. Personally, I miss it and yearn to return the next year.
This year, in fact, things are a little different: Today we have ended Part 1 of our field season – the part that involves excavation. But after a week’s break, we’ll begin a second field season. We’ll camp over at the Site Museum, just a small number of us. We’ll begin a new type of study for this area; it’s called a seismic survey, in which a large weight is dropped on the ground, over and over again as our field vehicle moves across a huge, flat area immediately south of Mount Olorgesailie. Our team will place sensors on the ground, which will record the echo – much like you would hear off of a distant mountain ridge – though this time the hard rock lies deep beneath us. What we’re most interested in is the accumulation of sediment on top of the hard rock, reaching up to the ground level. The time it takes to hear the echo will tell us how much sediment is under the ground.
Why are doing this? Our next big goal is to locate a deep and continuous series of sediment layers underground that extend back to about 600,000 years ago. An initial study showed that as much as 450-600 meters of sediment lie beneath the ground in the area south of the mountain. The deeper the pile of sediment, the more precisely it has recorded the environments of the Rift Valley in the Olorgesailie area. When we find the right spot – the deepest accumulation of sediments – our hope is to obtain a core next year that reaches hundreds of meters down into the ground, which can be drilled from a very small area on the current landscape. We have a big team of scientists lined up to study the core. We intend to figure out the environmental stresses and the variations in climate during the period when handaxe technology became extinct, after many hundreds of thousands of year of success of the handaxe makers. Eventually, Middle Stone Age technology, which is associated with the origin of our species, also developed and replaced the handaxes. Our study of the core will help identify the environmental conditions at the time of these dramatic shifts in our evolutionary history.
It’s an exciting project. The research, in the end, is what excites us about coming back to Olorgesailie every year. New challenges, new mysteries, new clues to help understand our origins. As for this year, I hope you have enjoyed reading about our time travels, and may some day visit this wondrous ancient landscape.
A Final Thought – Acknowledgements
As a final and lasting thought, I would like to offer a special tribute here to the Kenyan field team. The thirty men with us this season worked so hard, and with such great cooperation and sense of humor, to make our Smithsonian-National Museums of Kenya project a success.
Before acknowledging each member of the team, let me also give my big thanks to two others who were crucial to producing the blog. Katie Ranhorn gathered observations and helped write ideas for many days of this season’s blog. Jennifer Clark, who manages the logistics of our Olorgesailie field camp, also found the time to format the daily content and post the blog on our website. Great work to both Katie and Jennifer!
There’s no better way to end than to offer the following gallery of photos, with thanks to my colleagues on the Olorgesailie field team who excavate with such care and expertise; sieve sediment and find every little artifact and fossil with watchful eyes; and create an atmosphere at Kampi Safi that is like a ‘second home’ to me, and is warm and welcoming to the students and research colleagues who visit each year.
Goodbye from all of us on the Olorgesailie field team!