Animal Instinct: The World’s Most Unlikely Friendships [PHOTOS]

Photo: Reuters

A lion cub caresses a domestic cat as another lion rests in a private house in Kharkov, about 450 km (279.4 miles) northeast of Kiev December 15, 2005. The three-month-old lions live in the house of Tatyana Efremova who also keeps a number of other exotic animals.

Photo: Reuters

A mouse rides on the back of a frog in floodwaters in the northern Indian city of Lucknow June 30, 2006.

Photo: Reuters

A tiger cub climbs over piglets at a park in Guangzhou, south China's Guangdong March 13, 2007. The tiger cub was abandoned by its mother and is being raised by a sow. Picture taken March 13, 2007.

Photo: Reuters

A French bulldog plays with a two-week-old baby Bengal tiger, which was rejected by its mother, at Shirotori zoo in Higashikagawa, southwestern Japan May 11, 2007. The dog is nursing the baby tiger as if it is its true mother, according to the zoo.

Photo: Reuters

Nimra, a one-year-old cat, plays with chicks in Amman May 13, 2007. Nimra has been taking care of seven chicks after their mother's death a month ago.

Photo: Reuters

A monkey sleeps next to a dog at Lacor camp for internally displaced persons in northern Uganda June 8, 2007.

Photo: Reuters

Auan, a seven-year-old female cat, licks the body of Jeena, a three-year-old male mouse, at a farmer's house in the central province of Phichit, 450 km (281 miles) north of Bangkok on August 7, 2002. The animals owners say Auan found Jeena three years ago and has been his playmate and protector, including warding off dogs, since then.