Figure 4.

Demographic History of Five Arctic Marine Mammal Species

Pairwise Sequentially Markovian Coalescent model of the narwhal and four other endemic Arctic marine mammal species and δ¹⁸O levels through time based on data found in Zachos et al. (2001). x axis represents thousands of years before present (kya), upper y axis represents effective population size (×10,000), lower y axis represents δ¹⁸O (‰), and faded lines represent bootstrap values. Shaded gray area represents the last glacial period.