Mammals Like Us! Click on picture to see a bigger one. Whales are mammals because . . . They are warm-blooded. But instead of lots of hair (like most mammals), they have blubber to keep them warm! Did you notice the few bristly hairs in the top picture? Young gray whales have only a few hairs around their mouths, but they soon lose them. Adults may have some bristles on their chins. In the bottom picture, you can see dimples where hairs would grow. Hair would slow whales down in the water. They evolved over millions of years to have streamlined bodies protective layers of blubber instead. Next   Facebook Pinterest Twitter © 1997 – 2019 Journey North. All rights reserved.