Amazing Animal Pictures of 2015

Hippopotamuses fight in Serengeti National Park, Tanzania

A frog rides a beetle in Sambas, Indonesia

A polar bear plays in a pool at a zoo in Wuppertal, Germany

A seagull eats takeaway food left on the harborside in Cornwall, England

A farmer rides his pig named "Big Precious" during an interview with the media, in Zhangjiakou, China on Nov. 2. Instead of killing it, the owner decided to keep the two-year-old "Big Precious" as pet when its weight reached 1,322 lbs (600 kg).

Penguins swim in the pool during the annual stock take at London Zoo

Members of the Maasai Cricket Warriors pose for a photograph with the last surviving male northern white rhino named 'Sudan' in Laikipia National Park, Kenya

A rat searches for land mines and unexploded ordnance during a training session in Siem Reap, Cambodia

A flock of sheep seen through the streets of Madrid, Spain

Newborn birds open their mouths for food in a nest in Hong Kong

A swimmer free diving with a shark in the Azores, Portugal

A hippopotamus walks along a flooded street in Tbilisi, Georgia, U.S. on June 14, 2015. Tigers, lions, jaguars, bears and wolves escaped on June 14 from flooded zoo enclosures in the Georgian capital.

An ant gets caught in a raindrop in Bantul, Indonesia

Taronga Zoo in Sydney, Australia, witnessed the hatching of more than 20 veiled baby chameleons in March 2015. About five centimeters long, they were the first born at the zoo in over five years.

An Impala drinks water from a puddle in Mashatu Game Reserve, Botswana

Princess Stephanie of Monaco poses with an elephant during the presentation of the 39th Monte-Carlo International Circus Festival in Monaco

A flock of starlings perform their traditional dance fly before landing to sleep during sunset near the southern Israeli city of Rahat, in the northern Israeli Negev desert,

A snail sits on crocodile's head in Jakarta, Indonesia

Three-week-old orangutan Rieke gets introduced to the media in Berlin, Germany

A puppy enjoys an ice-cream during Woofstock Dog Festival in Pretoria, South Africa

A baby baboon seen in Tarangire National Park, Tanzania

Lemurs eat at Qingdao Forest Wildlife World in Qingdao, China