Figure 3 : Historical relationships and demographic history of
North Atlantic Harbour porpoises. (a) Maximum likelihood bifurcating
tree inferred by Treemix indicating a post-glacial colonization
of harbour porpoises from a southern refugium. The horizontal branch
lengths are proportional to the amount of genetic drift. (b) Inferred
changes on effective population size (Ne) through time with a mutation
rate of 2.56 x 10-8 and a generation time of 11.9
years. The start of the last glacial period (110,000 yBP) and the Last
Glacial Maximum (26,500 to 19,000 yBP) are indicated in gray.