What key evolutionary features evolved significantly later in the timeline of *M. primigenius* based on ancient DNA sequencing?

The genes responsible for producing thick, dense hair

While earlier mammoths like *M. meridionalis* were large and specialized grazers, the iconic thick, shaggy coat of the woolly mammoth evolved relatively late in the genus's history. Ancient DNA sequencing suggests that key adaptations for extreme cold survival, particularly the genes governing the production of thick, dense hair, may have evolved only a few hundred thousand years ago. This finding implies that early mammoths likely possessed thinner coats and developed their signature insulation only as a direct response to the rapidly cooling climate during the severe glacial maxima of the Ice Ages.