Vampire Bats Survive by Only Eating Blood—Now We Know How - 1

Two wildebeest lock horns.

Red foxes wrestle in snowbound Ontario.

Two brown bears spar in Kamchatka, Russia.

Hippopotamuses clash in Zambia.

Siberian tigers square up in Hungary.

Two white-tailed eagles collide in Poland.

Warthogs tussle in South Africa's Kruger National Park.

Two zebras charge each other.

Indian rat snakes coiled in combat.

Horses wield their sharp teeth in Sabucedo, Spain.

Musk oxen throw their weight around in Norway.

Spotted deer lock antlers in Karnataka, India.

Monitor lizards tussle in Sri Lanka.

Mountain goats collide in Sierra de Gredos, Spain.

Galápagos tortoises snap at each other in the Galápagos Islands.

Moose spar in Grand Teton National Park, Wyoming.

Hippos brawl in Masai Mara, Kenya.

Zebras duel in Tanzania.

Two kingfishers joust over a meal.

Lions grapple in South Africa.

Gorillas battle in Rwanda.

Snowy owls confront each other in Pennsylvania.

Red foxes duke it out.

Geladas scuffle in Ethiopia.

Lions mix it up in Botswana.

Bears grapple in Canada.

Lion cubs play fight in Kenya.

Wolves clash in Switzerland.

Pelicans squabble in Greece.

Rhinceroses face off against a wildebeest.

Red squirrels argue in Ontario.

Hippos locked in combat in Botswana.

Marmots wrestle in Canada.

White-tailed eagles fight in midair.

A black bear (left) and Kermode bear brawl in British Colombia.