Endangered species may be subject to different genetic threats, including low genetic variation, inbreeding depression and increased frequencies of deleterious genetic variants. From a conservation perspective, understanding these genetic threats is important to assess extinction risk. Moreover, there is also a need to understand the level genetic differentiation among populations, in order to assess the potential benefit, or cost, of translocating individuals from one population to the other. We are working broadly with conservation genetic issues on several different endangered animals, including Sumatran rhinos, arctic foxes and gorillas.
Several of our projects aim to examine the genetic consequences of demographic declines, using whole genome sequencing of both modern and ca 100 year old historical samples that predate the decline. We consider that this approach provides a highly accurate method to quantify the genetic threats caused by recent demographic declines, since it enables us to measure recent losses of variation, as well as increases in inbreeding coefficients and the frequency of deleterious genetic variation.
Specific questions that we are addressing include:
Norén K, Godoy E, Dalén L, Meijer T, Angerbjörn A. 2016. Context-dependent inbreeding depression in a critically endangered canid. Molecular Ecology, 25: 3309-1338.
Xenikoudakis G, Ersmark E, Tison JL, Waits L, Kindberg J, Swenson JE, Dalén L. 2015. Consequences of a demographic bottleneck on genetic structure and variation in the Scandinavian brown bear. Molecular Ecology, 24: 3441–3454.
Tison JL, Blennow V, Palkopoulou E, Gustafsson P, Roos A, Dalén L. 2015. Population structure and recent temporal changes in genetic variation in Eurasian otters from Sweden. Conservation Genetics, 16: 371–384.
Rodriguez R, Ramirez O, Valdiosera CE, Garcia N, Alda F, Madurell-Malapeira J, Marmi J, Doadrio I, Willerslev E, Götherström A, Arsuaga JL, Thomas MG, Lalueza-Fox C, Dalén L. 2011. 50,000 years of genetic uniformity in the critically endangered Iberian lynx. Molecular Ecology 20: 3785-3795.