Fig. 1: Genome sequencing of the extinct Steller’s sea cow.

A Reconstruction, aquarelle: The sailors of the Vitus Bering’s Great Northern Expedition (1741) cutting up the carcasses of killed Steller’s sea cows. Artist: Ekaterina Khritonenkova. B Geographical map of the Bering Sea region showing the distribution range of Steller’s sea cow during the Late Pleistocene (yellow), the archeological sites and localities (red circles) where samples of Steller’s sea cow were described, and the distribution of the last H. gigas population (blue circles). C The Hydrodamalis gigas petrous bone that was used for historical DNA extraction. D Steller’s sea cow, dugong, woolly mammoths, and Lena horse population size histories inferred using the Pairwise Sequentially Markovian Coalescent (PSMC) model. Population size history of each species marked by different color. Time is given in units of divergence per base pair on the X-axis, effective population size is shown on the Y-axis. Ky—means thousand years ago. My—means million years ago.