There was a period during my youth (freshman year of college) when I was decidedly pre-med. Coincidentally, this was also the period during which I first encountered my friend, the tooth person. During this period, I shadowed an emergency medicine doctor in the emergency department at a hospital in Seattle. He was incredibly supportive (shoutout Herbie!) and looked for any opportunity for me to learn and participate as he could.
A woman had come in with a broken tibia several hours before I arrived, but as the orthopedists were getting ready to set it, he sent me in. The orthopedists assigned me the only task I was qualified to do: hold her foot. This seemingly simple task turned into an hour-long ordeal testing most of my strength, both mental and physical. It was at that moment that I swore off bones.
While I arrived in Tanzania not nearly as opposed to bones as teeth, I was still skeptical. How could a bone, a small fragment of a greater unseen whole, be more interesting than the flesh and blood animals that we would soon see on safaris?
Today I was proved wrong yet again. I was convinced not that the fragment is somehow greater than the whole, but that the fragment can give us an incredible amount of information, that the fragment is not an answer but a clue.
We began our bone day at a now-familiar locale: the ~1.5 million year old gulley. There, the bone people (Dr. Dominguez Rodrigo) gave us a rapid introduction to taphonomy, namely human vs. carnivore bone damage. We learned how to tell the difference between cutting marks left by humans (which typically show striations within the cuts) and tooth marks left by carnivores (which are smoother and leave four distinct types of marks– punctures, furrows, scores, and pits). After a brief introduction to the patterns of green breakage (spiral bone breakages that occur when bones are fresh, rather than old and dry), we began collecting bags and bags full of bones with spiral breakages. Another instance of taphonomic bias: all the bones that were collected belonged to larger animals and the reason behind their preservation was the fluvial (river) environment they were deposited in.
What I entered with mild trepidation I soon began to enjoy: the bone hunt was fruitful compared to teeth, and the sun was still low. After an hour of mistaking vein marks for pits on bone fragments, we headed back to camp. Another lunch at Olduvai, another hour of friendship bracelet making. Life is good.
Afterwards, we headed back to our home-away-from-home: the museum. Isabella, Vivian, and Marlo delivered our final paleoanthropological methods presentations (tears were shed) on geomorphological reconstruction, paleoclimate, and microwear respectively. Kenyan visas were checked and the gift shop was shopped. We all said goodbye, in our own ways.
After heading back to bone capital (the camp) for our last night, we began examining our bones. At first, we were lost–the marks that had seemed so obvious when MDR showed them to us this morning had somehow disappeared, and we were left guessing. However, with some very patient guidance from Dr. Charles (a co-PI working with Dr. Manuel at Olduvai Gorge) and a great sacrifice from Marlo (lending her hand lens for us to manhandle), we began to understand the bones. Percussion marks around the notch leading into the spiral breakage meant hammering with stone tools: human damage. Slight scrapes in the bone surface near a spiral breakage: carnivore tooth damage. The more we looked, the more the bones had to say. For the most part–some of them retained their mystery even under 10X magnification.
Nom nom booonneeeesssss
No Alcelaphini updates today– the bones we collected were mostly broken long bones, likely with a few Parmularius bones mixed in, but largely unclear. Like the Leakeys, we were stumped when faced with only fragments. The presence of largely broken appendicular (non-torso) bones, and relative absence of axial (torso) bones did further clue us in to the paleohabitat present 1.5 million years ago in the gulley. This bone pattern indicates high competition for nutrients, which supports the open, savanna environment idea that we developed using our teeth.
Don’t worry–it wouldn’t be my blog if I left you without any Alcelaphini on our last night in Tanzania. We went for a sunset walk out into the savanna, and on our way out of camp spotted a rather incriminating collection of Alcelaphine skulls:
No comment.
A few more photos of our walk, and then I must bid you adieu:
Planning my escape into the Serengeti so I don’t have to go home,
Rose
