A Day at Olorgesailie, Kenya

The Smithsonian’s Human Origins Program is excited to participate in the Day of Archaeology 2013!

Our research scientists conduct field research at prehistoric sites in Africa (Kenya: Olorgesailie and Ol Pejeta Conservancy; Tanzania: Engare Sero) and Asia (China: Nihewan Basin and Bose Basin; Indonesia: Flores).  Today we’ll bring you into a day in the life of Dr. Rick Potts, the Director of the Human Origins Program. Today Rick is in the National Museums of Kenya, studying fossils and artifacts excavated at the site of Olorgesailie in southern Kenya.  But to give you a flavor of what fieldwork at Olorgesailie entails, we’ll be going back in the past — just two years, to July 26th 2011, when the excavations were going strong. Here is a modified version of Rick’s blog entry for that day from our Olorgesailie field blog:

Rick says:

One of the big-picture studies we do at Olorgesailie focuses on how the landscape changed over time, all the way back to the beginning of the sediment record more than 1 million years ago.  This area of the southern Kenya Rift Valley has the most precisely dated record of archeological and fossil remains in the world for the past 1 million years.  There is only one major gap in the time sequence, between the Olorgesailie and Oltulelei Formations – a gap that resulted from widespread erosion in the region between about 490,000 and 340,000 years.  But other than that, Olorgesailie presents a pretty continuous record from the handaxe era up to and beyond the time of the African origin of our speciesHomo sapiens.

My geologist colleague, Kay Behrensmeyer, and I have been studying landscape change in the region throughout the entire time period recorded in the Olorgesailie sedimentary layers.  Kay’s short visit draws to an end tomorrow, as she heads back to Nairobi and flies home to her family.  So we spent the morning going over the evidence for landscape change in the younger beds, the Oltulelei Formation, which includes the oldest Middle Stone Age excavations at BOK-2 and nearby sites.  Let me provide a couple of images that can help clarify what I mean by ‘landscape change’.

a river gorge wall with horizontal bands of grey, white, and tan. Green trees and round dark grey river stones in the foreground

Deep erosion along the river unveils many stratigraphic layers. Studying these layers helps us reconstruct how the Olorgesailie landscape changed over hundreds of thousands of years.For example, in the first image, you can see thick white bands and gray bands – where the upper layers were laid down on top of (and thus after) the ones below.  The white layer just above the line of rocks and trees is a thick layer of diatomite (look forward to me talking about diatoms tomorrow!).  The diatoms in the diatomite show that a large lake once existed at that point in time in the Olorgesailie area.  The gray band above it is a thick volcanic sand, which show two things – that there was a volcanic eruption in the vicinity, and that the debris from the eruption filled up wide stream channels that had cut across the region after the lake dried up.  So, count ‘em up:  that’s three major landscape changes.  First, the lake was present and then dried up.  Second, the dried-out landscape was eroded and water channels crossed the area.  Third, after a nearby volcano erupted, the ash and pumice and gravel was carried into the Olorgesailie region and it filled up the channels to form yet another, different kind of landscape.

One thing I’m especially interested in is how early humans responded to these big transitions in the environment.  Stone tools were the early humans’ version of a business card – they left the tools behind as if to say ‘We were here!’  Thus we use the stone tools to indicate whether our early ancestors were very successful or not in surviving the major shifts in the landscape, or perhaps repopulating the landscape after an especially difficult time.  Just think, 10 centimeters of volcanic ash blanketing the ancient terrain would have killed all the grass, forcing the abundance of grazing (grass-eating) animals to depart.  That’s a big drop in opportunities for obtaining meat from those animals.  So every landscape change affected the plants and animals – in fact, the entire ecosystem – and thus the early human toolmakers as well.

Now consider this next image:

Aerial view of the Olorgesailie landscape with white and reddish brown sediment layers and deep channels and ravines cutting through them

White and gray layers reflect the gradual build-up of the Olorgesailie Formation layers. They indicate many shifts between lake and land from about 1.2 million to 490,000 years ago. The darker brown sediments are ancient river sediments.  The narrow brown bands across the present-day landscape represent the erosion of large river channels, which were eventually filled up with silt and sand of the younger Oltulelei Formation. A big question:  What caused the repeated cutting of river valleys, followed by silting up of those river and stream channels?

After 490,000 years ago, the largest landscape changes we see were caused as river valleys were cut by erosion into the underlying Olorgesailie Formation.  These valleys were then filled up with brown silt and sand.  The filling was followed my more erosion as a new river valley formed.  This process happened at least 3 major times, and several minor times.

Aerial view of the Olorgseailie basin with green trees dotting the landscape of winding gorges with white and light brown and grey striped walls

The beautiful landscape of Olorgesailie – exposing layer after layer of landscape change, which could have resulted from climate shifts and earthquakes. Kay and I discussed two main causes:  Earthquakes or climate?  Earthquakes could have caused uplift of the Olorgesailie region, with rain and wind then carving out channels and creating valleys in the high ground of the uplifted landscape. The other possibility is climate.  That is, during dry times, the water levels across the region would have dropped, causing the occasional rain storm to carve the landscape down further and further over many years to reach the lower levels.  During wet times, as the regional water levels rose, the rivers and streams would have backed up and slowed, which caused the silt and sand in those flowing waters to be dumped within the channels.  In other words, cycles of erosion and deposition, over and over again as climate shifted over time.

At present, Kay and I are pretty certain that these big fluctuations of the landscape in the younger geological beds reflect strong climate cycles – that is, big shifts between dry times and wet.

The work continues as we keep seeking better clues to see whether we are right or not…


A Nevada CRM Archaeologist

This is my first post for the Day of Archaeology event.  I’d like to begin by thanking the organizers, advisors, and sponsors for conceiving of and making this event happen.  It’s important that we discuss archaeology across the world and get our work out to a broad audience.  All most people know about archaeology is what they see on the Discovery Channel or from Indiana Jones.

The road I took to get to a career in archaeology involved several u-turns and a few speed bumps.  Here is a quick history.  When I was a kid I wanted to be an astronaut, an airline pilot, or an archaeologist.  Since my family didn’t have the money for me to realize any of those goals I did what I thought was the next best thing and joined the Navy right out of high school.  I spent the next four and a half years working on EA-6B Prowlers as an aviation electronics technician.  During that time I went on a cruise on the USS Enterprise for six months in the Mediterranean and in the Persian Gulf.  We saw some great cities with great archaeology and history.  At this time, archaeology was something you saw on TV and included crusty old PhDs working in universities.  I never considered it as a career.

Near the end of my time in the Navy a random phone call landed me in commercial flight training at the Spartan School of Aeronautics in Tulsa, Oklahoma.  While there I received my private pilot’s license and finished the training for a few other licenses.  After a year and a half I transferred to the University of North Dakota to continue my flight training at the nations largest and most advanced collegiate flight training school.  UND Aerospace has an amazing program with state of the art aircraft and flight simulators.  It was a great experience.

While I was taking aviation classes I filled up my general education requirements with anthropology classes.  I still loved the science of archaeology, in particular paleoanthropology, but still didn’t see it as a career option.  I’m not sure why.  I think it was still just one of those fantasy fields that you never think you are capable of performing.

After a couple of years I started to lose my desire to fly commercially.  I just didn’t think I would get any satisfaction from shuttling people around the country for the rest of my life.  Sure the pay is good but there are a lot of things you can do that involve less stress if all you want is money.  I need a job that makes me feel good at the end of the day and that I look forward to going to everyday.  Since I still didn’t see archaeology as an option, even though I had taken most of the classes offered, I spent the next couple of years taking photography and math classes just for fun.  I know, I like math.  I’m probably the only CRM archaeologist that has used SOHCAHTOA to determine the exact angle for a transect.

During my penultimate year in college my professor, Dr. Melinda Leach, told me that I could graduate in one year with a degree in anthropology.  I just had to take all of the upper level classes and that would be it.  With no other direction I decided to go for it.  I had to take 18 credits during the fall and 15 credits during the spring and write, I think, five or six research papers during the year but in the end I graduated.  After graduation I went back to Seattle and worked with my brother’s father in law’s home remodeling company.  I hated it.

In the fall I went back to North Dakota to help with the big event that the department had planned the previous year.  We had Jane Goodall coming to speak to a packed house.  One day, while sitting in the student lounge, a former student, and friend, came up to me and said hi.  He was visiting because hurricane Katrina had destroyed his apartment in New Orleans and his company laid everyone off for a little while.  He asked what I was doing.  At the time I was getting ready to go on an Earthwatch expedition to dig in Olduvai Gorge in Tanzania.  After that I had no plans.  He asked if I had checked Shovelbums.  Shovel what?

I educated myself on, prepared my CV, and started on a job in Minnesota a week after I returned from Africa.  That was in October of 2005 and I’ve been in CRM ever since.  I’ve worked at all times of the year, on all phases of field archaeology and in 13 states.

In August of 2009 I began a one year MS program at the University of Georgia.  The program was intense but I received my Master of Science in Archaeological Recourse Management in July of 2010.  I’m currently working in the Great Basin of Nevada and love every minute of it!

So, I guess that wasn’t too brief.  My fiancé will tell you that brevity is not a trait that I possess.  Hopefully someone will get out of this that it’s never too late and you are never too old to get into the dynamic field of anthropology.   There are many paths that you can take to get to anthropology and there are just as many that you can take along your career.

My Chief in the Navy once told me how he decides whether a job or a position is right for him.  He said to look around at the people that have been doing your job and are at the ends of their careers.  Are they happy?  Are they doing what you would want to do?  My favorite thing about archaeology is that you can’t really tell what the future will bring.  You could be running a company, teaching at a university, or hosting your own show on the Discovery Channel, if they ever get back to science and history shows and away from reality shows.  The possibilities are nearly endless.

In my next post I’ll talk about the project I’m on right now and the wonders of monitoring.


Written northeast of Winnemucca, NV.

Accessing Egyptian archaeology through a British Museum exhibition

As an Egyptologist, currently working at the British Museum, I’ve been involved in a number of archaeological digs, but most of my research life has been devoted to trying to make sense of what other people have dug up and trying to share it with a wider audience. And that’s what I’ve been busy doing today.

A lot more ancient material than people might imagine has been found and then relatively ignored in pursuit of new discoveries, and it’s not always shared with as many people as it could be. Part of the work of the curators at the British Museum, whom I have been lucky to join as part of the BM’s Future Curators programme, is trying to make sense of the archaeological legacy that has been left to us. Curators have many different responsibilities, including current fieldwork, but they also persevere in contributing research on the museum’s existing collections, which is made freely available to the public in an online database, online research catalogues, and online journals. Outside researchers are also gladly welcomed to work on the collections; there’s always more that can be learnt from the objects.

Most of what I’ve been working on today relates to a BM UK touring exhibition, Pharaoh: King of Egypt, which I’ve been highly involved in, that opened recently in Newcastle before it tours the country. The exhibition explores the ideals and realities of kingship in ancient Egypt, and, as part of the BM’s Partnership UK programme, allows objects from the national collection to tour to museums outside of London.

I started today with further research into the objects that are currently part of Pharaoh. Exhibitions shed light on objects both literally and figuratively, bringing them out of storage to be shared with thousands of curious people, as well as being an excellent prompt to pursue further research into them. My hands on research, examining the details on objects up close, has sadly already passed, and now I’m chained to the computer and library books, fleshing out the context. Today I finally got round to working on one of my favourite objects from the exhibition, the massive wooden tomb guardian statue from the tomb of Ramses I. It towers at about two metres high and through the conservation work done on it, we learned that it is surprising in its construction as it is made from native Egyptian sycamore wood rather than the imported cedar wood which was usually used for large objects. Making sense of the object also involves tracing its history back to its discovery by Giovanni Battista Belzoni in 1817 and some subsequent misinterpretation in later publications!

Of course, as all archaeologists will understand, my research time didn’t last long, as administration, meetings, and other commitments took over. I worked on our slowly evolving project of making the Pharaoh website a better guide and online catalogue for the exhibition: today we added the exhibition themes to the website, which you can see here. Then we had a debriefing meeting to discuss what we learned during the installation of the exhibition at the Great North Museum: Hancock to help us better prepare for transporting and installing the objects in the subsequent venues around the UK. All sorts of things like scheduling, personnel, improved packing techniques, security, and providing contextual information and images were discussed.

Finally I also exchanged farewells with our visiting curators from Egypt and around the world, who were here for the past 6 weeks as part of the British Museum’s International Training Programme. I led a couple of sessions with the visiting Egyptian curators, as well as attending some of training sessions alongside the ITP participants, and I certainly learned as much from them as I was able to teach. On their last whole day here yesterday, they presented their ideas for future exhibitions based on some of the new approaches they’d learned from colleagues at the BM, partner museums, and each others. It was amazing to see presentations on exhibition concepts like the trade route between China & Europe or Somali wedding traditions, and given in partnerships such as Brazilian and Nigerian curators working together.

One can always learn more, whether from meeting new people or revisiting old objects, and continually asking questions is one of the most important tenets of archaeology.