Joseph Wambaugh changed my life.
I was 13 when I first discovered The Blooding, Wambaugh?s account of the Colin Pitchfork case: the first time that DNA fingerprinting was used in a criminal investigation. DNA in itself was already pretty fascinating to me. The idea that life in all its complexity could result from something so simple was both elegant and intriguing. But the application of the secrets of DNA, this meticulous examination of the ultimate nature of the individual, blew my mind. Forensics was the job for me.
Hence my decision to enter the Honours Genetics program at the University of Alberta. In my second year, David Paetkau, then finishing his Ph.D. on the population genetics of bears, gave a guest lecture to my biology class. His demonstration that DNA fingerprinting could be used to prove that multiple paternity occurs in grizzlies shifted my focus from humans to wildlife--or perhaps it was all of the slides of baby bears.
The University of Alberta requires Honours science students to complete an undergraduate research thesis. Seeing this as a wonderful opportunity to test the waters, I convinced Curtis Strobeck (population geneticist and David?s former supervisor) to take me on. Today, I am one and a half years into a Ph.D. built on that humble undergraduate project.
The focus of my research is population structure and gene flow in North American arctic canids: grey wolves and arctic foxes. I work in cooperation with local hunters and trappers throughout the north, who provide me with a small piece of fur or tissue from the animals they harvest. I use DNA from these samples to construct a fingerprint of each individual. By pooling the fingerprints of all animals from each region, I can determine the amount of genetic similarity among populations, which in turn reflects the amount of movement and interbreeding that occurs between them. Identifying the factors that determine these patterns--the distances separating populations, physical barriers preventing the movement of animals, hunting behavior, and interactions with prey species--is the fun part. An understanding of the driving forces behind canid movement is also of practical significance: Arctic foxes are the primary reservoir of rabies and canine distemper in the north.
Although not quite as exciting as collecting samples from live animals in the field, working with hunters and trappers has several advantages. Because population studies often require large numbers of samples, it is much faster and much less expensive to work with these individuals. And when local people are directly involved in the research, they have a greater interest in its outcome. As people whose livelihood depends on healthy and stable fur-bearer populations, trappers have a vested interest in ensuring sustainable harvests. Local involvement in, and support for, wildlife research is particularly important in the event that isolated or threatened populations are identified, as resulting management decisions could directly impact their lives. In my case, collaboration with local trappers has an additional advantage: Discussing and explaining my research with local hunters and trappers is an excellent excuse to travel in the north!
Working in a population genetics laboratory has been excellent training for a career in forensics. Although a variety of molecular methods are still in use, microsatellite DNA markers have become the marker of choice for population studies. They are reliable and repeatable and permit a wide range of analysis techniques. They are also highly sensitive to genetic differences between populations and between individuals. This sensitivity is especially important for a variety of wildlife forensic applications: identifying ("matching") individuals, assigning paternity, and determining whether an animal belongs to a protected population. In contrast, mitochondrial DNA (mtDNA) markers tend to mutate more slowly than microsatellites, often including variation specific to a particular species rather than an individual or population. In research situations, mtDNA is often used to address evolutionary questions. In forensics, mtDNA can be used for species identification. Y chromosome markers permit insight into male-mediated gene flow but can also be used to test an unknown animal?s sex.
Most law enforcement agencies require their forensic scientists to possess some kind of postgraduate degree. Several universities (primarily in the eastern United States and Ontario) now offer degrees in forensic science. However, there are definite advantages to pursuing a master?s or Ph.D. in a research-based environment. The focus of the program is often more specific and the choice of institutions and degrees much wider. In the case of genetics, improvements in technology have led to rapid increases in the number of labs addressing wildlife population questions. As the number of threatened and endangered species in North America increases, additional efforts are being directed toward these types of studies. Funding for genetic studies (through organizations like the Natural Sciences and Engineering Research Council, The World Wildlife Fund, Alberta Ingenuity, and the Alberta Conservation Association), particularly of large mammals, is becoming easier to obtain. Furthermore, as more populations are declared protected, and more and more species are listed under the Convention on International Trade in Endangered Species (CITES), the demand for forensic testing in wildlife cases is sure to increase.
As a student, much of my time is absorbed performing duties such as lab work, teaching, coordinating sample collections, and traveling. However, since I joined Strobeck?s lab, I?ve had the opportunity to work with conservation officers on 15 wildlife cases. I?ve also been qualified as an expert witness, although after fencing with the defense attorney for over an hour, I felt like anything but an expert! If I have learned anything from this experience, it is that solid population genetic research is essential to the practice of wildlife forensics. Whether calculating the strength of a match or determining that a poached elk was killed in a National Park, an understanding of the structure, connectivity, and variability of wild populations can be crucial to the strength of the case. It is often the quality of this underlying data that determines whether the bad guys go free.
With 4 years to go, my picture of life after graduation is still a little unclear. However, I hope to continue in the field of forensics, ideally combining casework with further wildlife population research. In the meantime, I hope my thesis work will address some equally interesting questions: how migration of barren-ground caribou impacts wolf movement, whether there is such a thing as the arctic wolf (currently listed "data deficient" by the Committee for the Status of Endangered Wildlife in Canada), whether arctic foxes migrate or just disperse, and how lemming cycles affect that decision. Whatever it is I end up doing next, I?m certain that there will always be another mystery that DNA can solve.