#6: Hairy Otters
Sea otters are one of the animal kingdom’s most remarkable experts in staying warm in frigid waters. Their secret lies in their incredibly dense fur. Sea otters boast an astonishing 600,000 to 1,000,000 hair follicles per square inch of their bodies, making them the most densely furred animals on Earth.
To put this into perspective, dogs have roughly 15,000 hair follicles per square inch, and humans typically fall between 800 to 1,290 hairs per square inch. This luxuriant fur acts as an insulating blanket, trapping a layer of air close to their skin and effectively preventing heat loss in cold ocean waters.