Hippopotamus mother and baby, Chobe National Park, Botswana

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We’re all smiles for World Hippo Day. Hippopotamus mother and baby, Chobe National Park, Botswana

It’s time to celebrate one of earth’s heaviest land animals on World Hippo Day! The hippopotamus, named “river horse” by the ancient Greeks, is an herbivore scattered across Africa below the Sahara Desert. Despite their wide range hippos are listed as a vulnerable species due to a loss of habitat. More closely related to whales than horses, hippos spend their lives in and around water, but they can’t swim or float. To breathe, they push off the ground underwater, a behavior they can do even while asleep. Hippos can live up to 40 years in the wild and possess the largest mouth of any land animal in the world, so smiling for the camera comes naturally.