North Africa is home to the greatest desert on Earth, the Sahara. This vast wilderness, the size of the United States, is the toughest part of the African continent. On the fringes of the Great Desert, Grevy’s Zebras battle over dwindling rivers, and weird naked mole rats avoid the heat by living a bizarre underground existence. Within the desert, camels seek out water with the help of their herders, while tiny barn swallows must go it alone and navigate across thousands of square miles of barren sand to find a solitary life-saving oasis.