Family of chimpanzees.

Elephant defecating

Mid Shot, zoo staff Larry Howard greets visitors at the Smithsonian’s National Zoological Park. Washington, DC. October 18, 2013. National Zoo and Friends of the National Zoo staff will gather at the Connecticut Ave. pedestrian gate to...

The Denver Zoo in downtown Denver including giraffes camels ducks and people enjoying a summer day at the areas largest zoo. Denver Zoo at Denver Zoo on June 12, 2012 in Denver, Colorado (Footage by Denver Post via Getty Images)

CLEAN: Interior shots of various butterflies on leaves inside butterfly enclosure at Chester Zoo. Butterflies at Chester Zoo at Chester Zoo on June 15, 2013 in London, England (Footage by Sky News/Getty Images)

CLEAN: Interior shots of giant green & brown bugs (grasshoppers) walking on zookeepers arm inside enclosure at Chester Zoo. Giant bugs at Chester Zoo at Chester Zoo on June 15, 2013 in London, England (Footage by Sky News/Getty Images)

HD: Pied Imperial Pigeon on twig in park, Thailand

Manatee Viewing, Lowry Park Zoo, kids stand at window, Manatee (Trichechus manatus) rolls past, other in, Florida, North Atlantic Ocean

A Grey wolf rests after eating at the Northern Lights Wolf center in British Columbia, Canada.

three zebra eat in zoo

Wolf in the Moonlight

Green Iguana on tree.

Gibbons are apes in the family Hylobatidae (pronounced /ˌhaɪlɵˈbeɪtɨdiː/). The family is divided into four genera based on their diploid chromosome number: Hylobates, Hoolock , Nomascus, and Symphalangus. The extinct Bunopithecus...

Iguana in the zoo

Family of chimpanzees.

Gibbons are apes in the family Hylobatidae (pronounced /ˌhaɪlɵˈbeɪtɨdiː/). The family is divided into four genera based on their diploid chromosome number: Hylobates, Hoolock , Nomascus, and Symphalangus. The extinct Bunopithecus...