A panda cub shows her teeth at the San Diego Zoo in San Diego, Calif. Ken Bohn/San Diego Zoo/AP/File
In Bali, a long-tailed Macacaqua monkey bares her teeth to intimidate anyone who would try to take her baby. Melanie Stetson Freeman/Staff/File
A chimpanzee named Omega yawns at a Brazilian sanctuary in Curitiba in the southern state of Parana. Rodolfo Buhrer/Reuters/File
A Tasmanian Devil named Tex stretches his jaws at the Taronga Zoo in Sydney, Australia. Tim Wimbo/Reuters/File
A juvenile female Virginia opossum bares her teeth as a strategy of self-defense at the home of Leslie Bale, the president of the Opossum Society of the United States, in Bellflower, Calif. Damian Dovarganes/AP/File
A rare albino alligator looks cheerful at the 'Serengeti' Safari park in the northern German village of Hodenhagen. Christian Charisius/Reuters/File
Lion cubs are shown Lecoqc zoo in the outskirts of Montevideo, Uruguay. Andres Stapff/Reuters/File
A silverback mountain gorilla named Agashya eats bamboo at the Parc National des Volcans in Rwanda. Melanie Stetson Freeman/Staff/File
A wolf yawns at the Leningradsky zoo in St. Petersburg, Russia. Alexander Demianchuk/Reuters/File
Toti, a newborn orangutan, looks at the camera from a bed at Taman Safari in Bogor, West Java, Indonesia. Achmad Ibrahim/AP/File
A Hardwicke's woolly bat grins in Lampanut, central Kalimantan, Indonesia. M. Struebig/Universiti Brunei Darussalam/Reuters/File
A horse shows its teeth in Glottertal, Black Forest region, southern Germany. Winfried Rothermel/dapd/AP/File
Tonik, a Shih Tzu/poodle who some say has a remarkably humanlike face, is up for adoption at a shelter in Indiana. Why is it that Tonik appears so human to some people?
Tonik, an 11-pound, 1-year-old dog available for adoption from the Homeward Bound Animal Welfare Group in Mishawaka, Ind., is looking for a loving and responsible household, preferably without children. He is part poodle, part Shih Tzu, and, if his photo is any indication, part human.
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