The golden langur (Trachypithecus geei) is one of the most range-restricted colobine monkeys, confined to the region between Sunkosh and Manas rivers in Bhutan and adjoining Assam (India). Despite its conservation significance, several questions regarding the species' population structure, relationship with closely related species, and ecological boundaries remain unresolved. Furthermore, the species occupies a rugged Himalayan landscape characterized by mountains, valleys, rivers, and forests, raising important questions about how these landscape features influence patterns of genetic differentiation and ecological variation.

My thesis addresses these questions by combining molecular genetics and ecological approaches. Using mitochondrial DNA, microsatellite markers, preliminary genomic analyses, and ecological niche modelling, I am investigating population structure within golden langur, its relationship with its sister species, the capped langur (Trachypithecus pileatus), and patterns of ecological niche overlap among the golden, capped, and Himalayan langurs (Semnopithecus schistaceus) at both Bhutan-wide and range-wide scales.

As this study continues to develop, the emerging results suggest that evolutionary relationships among these species cannot be fully understood through a single line of evidence. Instead, patterns of genetic structure, species divergence, and ecological niche overlap appear to reflect the influence of a dynamic Himalayan landscape that functions as both a barrier and a corridor. Thus, my thesis seeks to understand how biological boundaries are formed, maintained, and reshaped across the complex landscapes of Bhutan.