About the thesis:
The aim of the PhD project was to answer two main questions 1) population demographics of critically endangered Gobi bears, 2) evolutionary history of brown bears in Central Asia. Between 1996-2018, we collected 2660 non-invasive genetic samples from brown bears in the Gobi Desert allowing us to identify and genetically monitor 65 unique individuals over 20 years. Based on mark-recapture analyses, annual population size was only 23-31 individuals. Additionally, Gobi bear population has a highly skewed sex ratio (3M:1F) and high degree of inbreeding. This suggests that Gobi bears are one of the most critically endangered population in the world. For the evolutionary questions, we collected genetic samples from 119 brown bears across 8 poorly studied geographic locations in Central Asia and used traditional markers (i.e. mitochondrial DNA and nDNA microsatellites) and whole genome data. We also included Genbank data from brown bears in Europe and North America to understand the wide-range evolutionary history. We found 6-8 divergent brown bear lineages in Northern Asia, Europe (2 potential subclades), Gobi, Himalaya, Ancestral lineage in North Asia, North America (2 potential subclades). These results suggest that bears in Himalaya and Gobi are different evolutionary significant units and 2 subspecies including Ursus arctos gobiensis and Ursus arctos isabellinus. These demographics and genetic results highlight the critical status and uniqueness of Gobi bears and answered fundamental question necessary for effective conservation.