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Unit 5: The Evolutionary History of Biological Diversity: Paul Sereno | |
Interview: Paul Sereno
Paleontologist Paul Sereno, professor of organismal biology and anatomy at the University of Chicago, focuses on dinosaur and early avian evolution. During expeditions to remote regions of Africa and South America, his teams have unearthed numerous fossils that have helped scientists understand the evolution of dinosaurs after the supercontinent Pangaea broke apart. We were scheduled to meet with Dr. Sereno in Chicago on November 14, 2001, but had to conduct the interview by phone instead because planes were still grounded after the tragic events of September 11. During a week that was otherwise very dark, our spirits were brightened by Professor Sereno's stories about his expeditions and his science outreach projects with school kids. Which of your expeditions so far was the most challenging and memorable? The expedition that most defined my career was the first one to Niger in 1993. I took a very young crew on a wild trail that had us packing six Land Rovers in London, ferrying across to Algeriawhich was a chancy place to travel at the time and then threading with our overpacked Land Rovers through more than a thousand miles of desert to Niger, which had just elected its first president. Many of our people were seeing desert for the first time, and we encountered all sorts of delays and problems due to political situations. Half of my team departed because they feared for their lives. I then continued with the remaindera wily group of very young studentsand the ten of us discovered and excavated 6 tons of dinosaur bones. We returned across that very desert and managed to all 6 tons of dinosaur bones onto a ferry, making all our future work in Africa possible. The story of that expedition is truly a great one, about which I'm writing a book. When you come out of something like that, you realize the great thrill of coming to the edge. And the edge was when I actually cancelled the expedition halfway through because I thought it was all over. But it came back to life, and we went into the desert and made it work. I also met my future wife on that expedition! So it had all the elements. When you're recruiting your expedition teams, what qualities do you look for in students and other crew members? Well, it's one thing if you're going to a place like Wyoming. But if you go to places such as the center of the Sahara, then you need to find a team that can focus their physical and mental energiesabout equal amounts of eachon a project that, I think it's fair to say, will be the most daunting and challenging in their lives up to that point. And to join these kinds of expeditions, you need to be a certain kind of persona person who is adventuresome, preferably with some experience in fossil recovery. But most important, you need to be a person who thinks about other peoplethe kind of person who let's someone else go first in linebecause what you find in an expedition, when the going gets tough, is that the most critical factor is a person's ability to work in a group, as a team member. And, of course, on these kinds of expeditions, you need to be a person who can withstand physical and mental stress at a level you have probably not experienced before. You'll find yourself in a very foreign environment and set upon by very trying weather conditions such as extreme heat and sandstorms, eating foods you're not used to over long periods of time, and exerting yourself in these circumstances. But as a leader, I have to fix in my team members' minds what I believe is the truth, which is that this is one of the most exciting things you can do in a lifetimeyou are really making history. How do you know where to look for dinosaurs? Your first clues about location are based on what past explorers have found. And the geography and geology of most areas has been mapped well enough so that you know roughly where there is rock of dinosaur age exposed. But there's usually, a huge area to cover, so the team has to be very organized. It may mean five or six prospecting episodes over huge areas of desert in 120°heat. Sometimes you just have to blanket cover as much area as you can. Other times you begin to see a pattern of rich sites that you can focus on. Hand-held satellite navigation devices have made the whole process more efficient. It allows us to return precisely to a site we found a month earlier. This means we can charge out into the field and locate many things we might want to collect and then organize our collecting after the initial exploration instead of trying to find something we walked away from on a rather featureless landscape. How do you extract a dinosaur skeleton when you find one? We mostly use very simple tools, from the small to the large: dental picks, awls, hammers, sledgehammers and chisels, and picks. Occasionally we've had to use jackhammers, but they're usually not very useful. Then we have to have block and tackle to lift big fossils and rocks. If it's a newly described dinosaur, how do you choose a name? It's up to the whole group to come up with a name. It has to be a name that captures something about the animalabout its history or form. But the best name is also an aesthetic thing, sonorous and short and catchy enough for a kid to say. And of course, it has to make sense when translated from its classical word roots. Combining all those criteria, we've had the most interesting names. For example, we got to choose the name for the first reconstructed predatory dinosaur from the Cretaceous in Africa. We called it Afrovenator, which means "the African hunter." We also found a big, long-necked, plant-eating dinosaur23 m longthat was a contemporary of Afrovenator. Even before we left the field, a graduate student came up with Jobaria for this giant. It was based on "Jobar," the name the indigenous Tuareg people in Niger used for a mythical giant creature. When you find a dinosaur, who has rights to the skeleton? That situation has been changed, both for domestic paleontology and for expeditions to other countries. Before, say, 50 years ago, paleontologists might take fossils out of Montana or some other state out West without regard to museums in those states. Today, you can't find a T. rex on public land in Montana and just drag it back to your favorite institution on the East Coast. And you certainly can't go to another countrynot legally, at leastand just dig up a dinosaur and take it home. Even to dig in foreign countries, and certainly to take national treasures out of the country even temporarily, requires diplomacy with local scientists, politicians, nomads, villagers, and ministers. All sorts of situations arise. In Niger, for example, scientists are trying to establish a new museum for a dinosaur collection. Most specimens are on temporary loan. The bulk of the material will go back to the country of origin. To have these fossils lodged on a shelf somewhere here, thousands of miles away from where they were found, with no opportunity for people in the country of origin to study or even look at the specimensthat's not a situation we want to promote. How did you get started in paleontology? It was certainly not a talent that was apparent early on. Although I enjoyed nature and liked the outdoors as a kid, I was hardly a stellar student. In fact, when I was in the sixth grade, I couldn't even imagine myself graduating from high school. I was a very unsettled, unkempt student even into my first couple of years of high school. Then I found myself studying art. Through art, I gained a confidence that I could actually apply my talents and energy to something. And I was able to improve my studies enough to go to a state college, thinking I would become a studio artist, but also taking an interest in various sciencesmainly in the field of anatomy, which was related to what I was doing in art. We were drawing human bodies, and I often found myself drawing skeletons. The one very dramatic event in my pathway was tagging along with my older brother, who was applying to graduate school and had an interview about studying paleontology at the American Museum of Natural History in New York. I was just totally blown away by all the things that were happening therethe lore of the historical work in the field of paleontology and the scientists who had come before, the great expeditions, all the active work that was ongoingI just found the whole field intriguing. So it's a wild and wooly tale of just discovering what talents reside in you and what you're really interested in and then combining your interest and energy. And the discovery of those talents led me to paleontology and the things I do today. As a paleontologist teaching skeletal anatomy to medical students, do you connect evolution to lessons about the human body? Oh, yes! Many of the clinical problems, such as deteriorating joints, occur because we are not perfect designs, but animals with evolutionary backgrounds. Evolutionary solutions to things like walking and bending over are imperfect. And the changes that evolved most recently in humans are perhaps the ones most poorly integrated into our anatomy. Those are often the points where we have problems. Speaking of teaching, did your personal educational experience inspire your interest in helping children discover their own talents and interests through Project Exploration, the science outreach group initiated by you and your wife, Gabrielle Lyon? Yes, you come away realizing that there are all these undiscovered talents in any human being. You will only be able to discover a very few of them. There are things you thought you couldn't do, only to discover the talent at a different point in life. And there are things you'll never even be able to test, be it musical skills, acting, or some other talents that are inside you; you may never be able to experience those, because of the particular trajectory of your mind. So we hope we get to discover at least a few of our talents. And that's what I try to impress on kids through Project Exploration. I feel I have sort of a calling or mission that way because of where I've come from and from not following a completely conventional pathway. I can relate to kids who are struggling in the classroom format to find something that interests them, because I was very intimidated in that setting and, for whatever reason, it wasn't working in my case. So in my spare time, I enjoy including kids in my research life. We just returned from a Wyoming trip with kids from the inner city who got to experience camping on a ranch. And we actually made a major discovery in the field. I collected a 5000-pound block of tyrannosaur with a bunch of junior high and high school kids. Those kids found out the natural world is exciting and that science is adventuresome, and that it involves a variety of talents. And once you discover those talents, it's a matter of organizing and focusing that energy. That's all it was in my life. And I get a huge amount of enjoyment in seeing kids inspired to go on toward careers in whatever they discover they want to do.
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