Imagine that you are a chimpanzee foraging in the doum palm forest by the Turkwel River, and that you have all the palm nuts high up in the trees, what would you do to get them? That was exactly the question our field school students have to think about at the beginning of the Archeology module! In this module of the Fall 2015 Origins Field School, we are with Dr. Sonia Harmand from Stony Brook University. Dr. Harmand is one of the co-directors of the West Turkana Archaeological Project (WTAP). She has been working on the west side of Lake Turkana for several years and has taught the Archaeology module many times. Earlier this year, she and her colleagues published in Nature the discovery of the earliest known stone tool technology about 3.3 million years old. Students are going to learn what is unique about the earliest known tool making techniques with Dr. Harmand. Stay tuned!
Back to the palm nuts and what we can learn about tool using and tool making. For a long time, researchers thought that tool using and tool making are unique to humans because we are so smart! In fact, other animals in this world can also make and use tools. For example, a chimpanzee can use its teeth to shape a straw and use it to fish for termites. Tool using is even more prevalent! Chimpanzees can use a hammer stone and an anvil to crack open nuts. Sea otters can also use a rock on its belly to crack open mussels. Even a bird can use a small stick to fish for grubs in the trees. So it seems that tool use is not unique in humans but the consensus is that only humans (and our ancestors) can make stone tools of specific shapes. So to understand the root of tool using making and use, we went out for a little foraging pretending that we were just a group of chimpanzees!
Doum palm nuts are very common along the Turkwel River and their fibrous husks are rich in sugar and vitamins. But the first challenge we had was that we could not use any preexisting tools to help us collect the nuts! So some of us chose to shake the palm trees, but the nuts were surprisingly stubborn! Others managed to reach out for the nuts by building a human ladder, but the nuts they collected were mostly unripe… The most efficient way to collect nuts is actually to throw a rock at the nuts, but it still requires a lot of skill!
After some really costly foraging activities and thanks to the sympathetic help from some local Turkana kids, we finally collected a decent number of nuts to work on! To get to the relatively nutritious part of the husk, the skin of the nuts has to be removed. However, the skin is very hard: it has a shell! You know what a chimpanzee would do? It would use a hammer stone and an anvil to crush the shell! So we set out to look for stone hammers and anvils from the nearby river deposits. The anvil and the hammer stone have to be strong enough so that they won’t break during the heavy-duty pounding and smashing. Fortunately, our students knew very well how important a good set of tools is! And everybody did very well in removing the skin of the palm nuts. Whether we like the taste of the husk, though, was a totally different story! Take a look at our pioneering tool users and the dawn of a technological revolution!
Next, we are going to learn the different ways that stone tools were made in human evolutionary history. Stay tuned for more!