University professor David Greenwood doesn't usually work with animal fossils. But that all changed when he was excavating plant fossils in Driftwood Canyon, B.C., in 2010, and one of his students found a fossilized jaw. The jaw, dating back 52 million years and about the size of a fingernail, belonged to a previously unknown species of prehistoric hedgehog. A year later, a Greenwood-led expedition struck again -- discovering a hand-sized jawbone belonging to a prehistoric tapir. The hedgehog would have been smaller than a mouse, while the tapir was similar in size to a large dog.
The fossils were discovered in Driftwood Canyon Provincial Park, a place rich in fossils, in northern B.C. Greenwood had taken students there to collect samples on numerous occasions. The professor at Brandon University, where he moved from Melbourne after getting his PhD from the University of Adelaide in South Australia, recently talked to Free Press reporter Oliver Sachgau.
FP: Can you tell me the story behind the discoveries?
GREENWOOD: I was there with Bruce Archibald (a colleague) and Megan Gilbert, a student from the University of Saskatchewan, who was doing a summer internship with me, and two students from Brandon University. The student from Saskatchewan is a important player in the discovery of the fossils. She had some experience finding fossil teeth, in particular for mammals. So we're working away, and looking for flowers and leaves and insects and things. Megan, because she had prior experience -- her brain is tuned to find the bones, teeth in particular. And this thing is tiny. The jaw fragment is about the size of your fingernail. So that was the first discovery. It was chance in that we weren't looking for mammals, and luck in a sense that we had someone with us with the right intellectual makeup to find what she did.
Then in 2011... we were digging fairly systematically, and we had a colleague from the University of Utah, who looks at the chemistry of rocks, and he had his graduated student. (The student) was digging away at coal in the park, and he happened to strike, with his pickaxe, at this jaw, about the size of the palm of your hand. You don't expect to find bones in coal. But this was sitting right on the surface. He recognized immediately it was something important. Sadly his pickaxe had hit it, and a piece of it went tumbling down into the creek and was lost. Lucky for us, the important part was left.
FP: How common is it to make discoveries like this, through luck?
GREENWOOD: It's surprisingly common. (But) we often have an idea of where to look, and certainly this is a place where, based on prior knowledge, there is an expectation we'd find mammals. And in fact there was a fairly obscure report of a mammal skeleton the size of a mouse that had been found at this site decades ago and kind of forgotten about. So it wasn't a shock or surprise that we found these mammals, but certainly dumb luck came into it because we weren't looking for them. And that's often the case. You're looking for one thing and you find another.
FP: How important is a discovery like this for a career like yours?
GREENWOOD: I'm a plant guy, so this is sort of peripheral to my personal research. However, it's pretty exciting stuff. Most people, you talk about plants, they're like "Oh yeah, that's interesting, I like trees." But you tell them you found a hedgehog or a tapir, people go "Oh wow, animals!" It's human nature. We're more in tune with animals than we are in plants.
The excitement for me in terms of my career, well, wow, what a rush. I don't hide it. It's exciting that so much attention is being paid to this research and my role in it. It's profile, that's the right way to use it. It builds my profile. My two colleagues did the high work in terms of identifying these two animals -- Jaelyn Eberle and Natalia Rybczynski. (Rybczynski, the study's co-author, is a palaeobiologist at the Canadian Museum of Nature in Ottawa, while Eberle, the study's lead author, is a geological scientist at the University of Colorado.)It looks like the three of us will go forward and do more work together, so from a career perspective it looks like there's a new network there. And that's, I think, the key point.