This morning, I defied all odds and learned an entire year’s-worth of content in less than an hour. Don’t believe me? Good, because I certainly didn’t learn everything, but I got the basics.
Dr. Manuel taught us how to identify different types of bone damage, including the time of breakage, method of breakage, and type of animal that inflicted the breakage. We returned to the Gulley, which we previously surveyed for teeth, to now collect any “green-broken” long bones. That is, fossilized long bones (typically extremities) which were broken near the time of death.
Dr. Manuel Teaching Rose, Caroline, and Me Something Important
Green Breakage vs. Dry Breakage
We spent only an hour surveying. The fossil supply was so vast that it took nearly no time to gather a sufficient sample size. Bones in-hand, we traversed back to the BK dig site to continue with our final day of excavations. Again, I worked on the same quadrant as yesterday. However, I was only able to uncover two 1.4 million-year-old quartzite fragments. Lame! (I’m absolutely kidding)
Dr. Manuel, Isabella, and Anna at the BK Dig Site
After lunch at the campsite, we went to exploit the Olduvai Museum’s Wi-Fi and conduct our final student presentations.
Once again, we found ourselves back at the campsite. It was time to employ the knowledge we’d acquired this morning – all our bones laid out, we carefully inspected our fossil collections to discern as much information as possible from individual scratches and breaks. I sorted my findings based on the presence of carnivore- or hominin-signatures. Among other variables, I was looking primarily for deep scratches, using a hand-lens to inspect the surface for micro-striations. If a scrape lacks micro-striations, it was likely applied by a tooth with polished enamel, as opposed to a rough-surfaced rock. These point strongly towards exploitation by carnivores, such as lions (large felid!). Deep scrapes with micro-striations or percussive marks were likely inflicted by early hominins.
My Bone Identification Notes
Dr. Manuel helped us incorporate our findings into the habitat reconstruction we previously made. Excitingly, our second sample supported the theory we had already constructed: most bones were highly exploited by carnivores, which suggests a high level of competition – high competition is typical of very open environments, like the one we concluded from our previous habitat reconstruction.
Tonight is our last night in the tents. Although I can’t honestly say I’ll miss sleeping on the ground, I will certainly miss our tent village and calling out goodnight wishes to the other students before we doze off. It’s a bittersweet evening in Africa tonight.
Goodnight and sweet dreams!
