A Look That Says "I would run if I were you."

This cool cat is one of the four Siberian tigers that call the Philadelphia Zoo home.

Siberian tigers, also known as Amur tigers, are the world's biggest cats, capable of growing 12 feet long and weighing upwards of 300 kg (660 lb). Their keen and stunningly deep eyes see six times better than humans' do. Thick coats and an insulating layer of fat allow them to sustain temperatures as low as -42 degrees Celsius (-45 in Fahrenheit). Add all those up and you've got quite the predator on your hands. Sadly, the Siberian tiger is highly endangered. It is estimated that only about 350 remain in the wild.

Learn more about Siberian tigers:

-at National Geographic

-at the World Wildlife Fund

-at WCS Russia

Photo credit: fPat Murray / Flickr

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