Stories are as diverse as the people who tell them. Some stories are epic, sweeping, like the tales of Gilgamesh and Beowulf. Others are personal, detailed, like Salinger’s Catcher in the Rye. This week found BU Stories on the first floor of 232 Bay State Rd, speaking with a man who confronts what is arguably the most epic story of all—the story of human evolution.
For a long time, the only way we knew how to tell our own epic story was through the stories of individuals—or at least, the bones of individuals that make up the fossil record. Professor Jeremy DeSilva is an assistant professor in the Anthropology department here at Boston University. His particular area of expertise is the feet and ankle bones of modern primates and our ancestors. Dr. DeSilva takes these individual bones, notes details– a fully fused growth plate, for example– and uses them to create a full, fleshy picture of who these organisms were and how they moved. We talked about how he came to science and anthropology, the difficulties of being objective in the scientific field, and the stories that bones have to tell us about our history as a species.
Amalie: How did you come to anthropology?
Jeremy DeSilva: Even as a little kid I knew I was going to be a scientist. I was just curious about how the world worked. I had excellent science teachers that reinforced to me that you can ask questions in science and not be scolded. In science, you can ask questions like, “Why is the sky blue?” and that’s a really good question and it turns out to have really complex answers. The answers always lead to more questions, which is what I liked about it too. There’s this kind of never ending cycle of curiousity.
After undergrad, I got a job at the museum of science, teaching. My boss wanted us to update the Human Evolution exhibit and she asked me to research what would be in a new exhibit on evolution. I started reading. I got obsessed. I was bitten by the hominin bug. My boss at the museum said, you have found what you are meant to do. Go.
Why did you choose feet to focus on?
It could have been anything. What I was interested in was, how can we take these old bones and turn them back into the flesh and blood creatures that they belong to? Animals that moved in a certain way, and ate things, and lived and breathed and did all sorts of wonderful things, how do we reconstruct that from the bones? It’s a science called functional morphology. In order to figure out what the old bones were doing, you have to understand a tremendous amount about what animals do today, and how the shapes of their bones correspond to the things that they do. I got interested in climbing. Both the question of how did apes evolve and then the human ancestors, were they still climbing. I thought both questions could be better addressed if only we knew more about how apes climbed. I thought the way to get at this is to get into the forest and look at what they do in the forest.
Originally, scientists believed that the growth of the brain was what set us apart from apes. This idea was heavily influenced by Victorian biases at the time. What effect does an imposed narrative like that have on scientific progress?
Science is, at its purest form, entirely objective. And yet it’s being done by emotional, subjective apes. Humans. So there’s this conflict, between interpreting data in a purely objective manner, and being influenced by where you live, when you live, all the other things going on around you. The beauty of science is that the scenario you just laid out, that the brain came first, is a testable idea. The idea that the brain came first is wrong. Ideally, a scientist should never be afraid of being wrong. It’s when people get so possessive of their own ideas that even in the face of compelling data they still grip onto their ideas, that’s when the science suffers. Down the road, some of the ideas that I’ve had may turn out to be completely wrong. That’s okay. If I’m wrong, my wife will still love me, my dog will still lick my face. I can take comfort in the fact that I proposed a thought that was seriously considered. Everything in science is subject to that. It is false to say that science is 100% objective, but it has and will span enough generations that it weeds out the ideas that were being influenced too heavily by non-evidence based thinking.
Do you have a fossil that’s particularly important to you?
There’s a little child known as the Dikika child that I had a chance to study, and the feet are scientifically amazing, but when I got to see the original fossil, of course it’s the skull that you look and and just, wow. This little girl was three years old when she died and she could never fathom that her donation to the world, by dying where she did when she did, she’s going to provide so much information to us about us, about where we came from. Its those kind of fossils that get me, that are complete in that way. But every single bone tells an incredible story. Every bone deserves to have its day.
Every dog has its day and so does every bone?
Exactly. Exactly. That’s why I love what I do. There’s so many stories like that in these fossils.
For more information about Jeremy DeSilva and his research, check out his Faculty Profile here.