Phylogeography and genetic diversity in Red Knots (Calidris canutus)

M.Sc. thesis. 2003. Deborah M. Buehler. Graduate Department of Zoology. University of Toronto PDF

This thesis examines phylogeography and genetic diversity in a migrant shorebird, the Red Knot (Calidris canutus).  I sequenced and characterized the control region of knots and verified that the sequence was mitochondrial in origin.  I then used control region sequences and coalescent analysis to reconstruct the demographic history and biogeography of knots. My analysis indicated that knots probably expanded eastwards across the Arctic from a severely bottlenecked population in eastern Eurasia as Pleistocene ice sheets melted.  Population divergence times suggest that all six subspecies of knots arose within the last 20,000 years or so, and evolutionary effective population sizes of females were small (Nef = 2,000 to 14,000).  To examine genetic diversity, I analyzed control region sequences, amplified fragment length polymorphisms and microsatellites, which indicated that knots are genetically depauperate relative to Dunlins and other bird species.