Sunny Hwang received her Ph.D. in Vertebrate Paleontology from Columbia University. Like most paleontology grad students at Columbia, she conducted her Ph.D. research at the American Museum of Natural History, where her research advisor was Mark Norell, a curator in the paleontology department.
Sunny's love of dinosaurs began at around age seven, when she picked up a stack of books on dinosaurs at a garage sale. Her interest was rekindled several years later when she read Michael Crichton's novel Jurassic Park. She was surprised to find how much the accepted view of dinosaurs had changed since she was in elementary school. "I grew up thinking of dinosaurs as sluggish, cold-blooded, giants" she says. "The view of dinosaurs changed in the '80s to include a lot of smaller, faster, warm-blooded hunters. That book reflected a lot of the new research."
As an undergraduate at Columbia University, Sunny studied molecular biology, a subject she had been fascinated with since high school, and worked as a lab technician, assisting researchers who were studying the functions of specific genes. To study a particular gene, DNA is transferred into bacteria, which reproduce and create millions of copies of the genetic material being studied. "Bacteria are like little DNA factories," she explains. "You always need a supply of stock DNA to work with." Her job included growing colonies of bacteria, then purifying the DNA from it. The DNA was sometimes injected into the cells of mice to see how altering a gene affected their development, so Sunny had to tend large colonies of laboratory mice, a task that did not thrill her. "Lab mice are not very sweet," she says. "But I guess I can't blame them."
In her junior year at Columbia, Sunny realized that she did not want to spend the rest of her life in a molecular biology lab. "I thought molecular biology was interesting," she says, "but the focus was so specific, so small. There are thousands of DNA researchers, and each one spends years studying one little gene." The pace of biological research was also much too slow for her. When growing cultures and detecting the presence of DNA, she explains, "You wait, and wait, and wait some more. It takes three days before you even know if it worked."
Though it was late in her college career for such a major change of direction, Sunny decided that what she really wanted to be was a paleontologist. To make up for lost time, she spent the summer before her senior year as a research intern at the Lamont-Doherty Earth Observatory, analyzing fossilized lake sediments to study the ancient climate, and then took the only dinosaur course available to undergraduates, which only cemented her decision. Reveling in the pleasures of handling fossils, she says, "I can see bones; I can feel bones; I can touch bones" – a welcome contrast to working with tiny molecules she would never see.
Becoming a dinosaur expert also appealed to Sunny because it would give her a great opportunity to share her love of science, especially with children. She had gained some experience as a teaching assistant in the chemistry lab at Columbia, and her father, a pharmacological researcher, had been a college professor before entering private industry and starting his own company. Her parents, who were both born in Taiwan, were "really big on education – the whole immigrant thing," Sunny says.
As soon as she began her Ph.D. program, Mark put her to work with hands-on projects that would quickly get her up to speed on dinosaur anatomy and research techniques. "Mark is fond of giving his students small projects that they can finish quickly and get a lot out of," Sunny says. In her first year, Mark gave her a skull fragment to study, for example, because he knew Sunny had not studied skulls before, so it would be an opportunity for her to learn something new. Just recording her observations required learning a whole new set of terminology. "You can't just say, 'that bump on the front of the head,'" she says with a laugh. "You have to say, 'the anterior proximal dorsal whatever.'"
For her research, Sunny spends hours closely examining fossils, checking for specific traits or "characters" that help reveal how each species fits into the big picture of dinosaur evolution. The Museum's approach to studying all plants and animals, whether fossilized or otherwise, is called cladistics. Cladistics involves organizing species according to shared, derived characters that indicate a common ancestor.
When studying theropod fossils, Sunny uses a checklist of 251 characters developed by Mark Norell, James Clark, and a former graduate student, Peter Makovicky, and modified by others in their research group. Each item on the list offers specific alternatives that are assigned a number, such as "veined feathers on forelimb symmetric (0) or asymmetric (1)." If the character cannot be found, Sunny records a question mark, then moves on to the next item: "Orbit round in lateral or dorsolateral view (0) or dorsoventrally elongate (1)." Some characters have a third option, numbered (2). When she has checked all 251 characters, the resulting string of zeros, ones, twos, and question marks is entered into a chart on her computer.
This systematic approach yields a detailed data set, or "matrix", that enables related species to be instantly compared according to all known relevant criteria. "They're always looking for more characters to add," Sunny says. "The more data you have, the better." Each newly discovered fossil provides more data for the matrix and helps fill in the picture of dinosaur evolution.
The main benefit of this matrix is that the entire data set can be analyzed by a computer program that comes up with hypotheses about which dinosaurs descended from which. The goal is to create trees called cladograms, in which branching lines show new characters arising and being passed on to later generations. The computer program sorts through all the possible scenarios and comes up with the simplest explanation for the existing evidence.
Because the Museum is a major center for dinosaur research, fossils from around the world are sent there for analysis, and many other new specimens are unearthed during the Museum's own expeditions to Mongolia. It was a thrill for Sunny to study these fossils, long before the rest of the world saw them. For instance, a dazzling new dromaeosaur fossil, covered in feathers from head to toe, was sent to the Museum from China while she was in graduate school. Mark considered it one of the 10 most important finds he'd ever seen, and its picture landed on the front page of The New York Times. To Sunny and others around the office, the fossil was affectionately known as "Dave." "We were all very proud of him for being so fascinating," Sunny jokes.
Sunny is equally excited by the thrill of discovery provided by going on fossil expeditions. After hours of sifting through dirt, she says, "The moment when you find something is just fantastic." Sunny has participated in several small expeditions in North America, from Nova Scotia to Virginia, and a long summer expedition to Wyoming. She made many trips to China to study specimens that have never been loaned to outside researchers, and also accompanied Mark on a dig in Mongolia. She also traveled to nine different museums across North America to collect samples for her Ph.D. dissertation project on dinosaur tooth enamel microstructure. After graduating from Columbia and leaving the Museum, she traveled to Mongolia with colleagues from graduate school (who are also friends) on their own digs. "It's a lot more work to organize your own expedition, but more rewarding as well, because you can do whatever you want," she says.
In her rare moments of leisure time, Sunny enjoys cooking everything from the complex recipes her mother learned in Taiwan to a complete Passover Seder featuring a recipe for chicken soup from her husband's mother. She also enjoys drawing and does her own technical drawings for her published papers. She is currently trying to instill a love of paleontology in her two young daughters. Her attempts seem to be successful so far: Her older daughter went on her first fossil-hunting trip at the tender age of three, and the younger one does not object to her dinosaur-print sheets.