zoo

In December born male zebra Jambo, left, plays with it's mother as it is enjoying the outdoor enclosure while shown to public for the first time at the Zoo in Wuppertal, Germany, Wednesday, April 16, 2014. (AP Photo/Frank Augstein)

Frank Augstein/AP

Jambo, a four-month-old zebra, plays with its mother while being shown to the public for the first time at the zoo in Wuppertal, Germany Read more

Lemur offspring at Eberswalder Zoo...epa04139812 A photo made available on 25 March 2014 shows a female ring-tailed lemur (Lemur catta) carrying her twin offspring at their enclosure at the zoo in Eberswalde, Germany, 24 March 2014. Several monkeys were reported to have given birth to their offspring at the zoo in the past weeks.

Patrick Pleul/EPA

A female ring-tailed lemur carrying her twin offspring at their enclosure at the zoo in Eberswalde, Germany. Several monkeys were reported to have given birth to their offspring at the zoo in the past weeks. Read more

Gorilla mother Kumili arms her newborn at the zoo in Leipzig, central Germany, Thursday, March 20, 2014. The baby gorilla was born during the night between 10 and 11 March 2014 and its sex is still unknown. It's the second  gorilla baby born  within four month in this monkey group. (AP Photo/Jens Meyer)

Jens Meyer/AP

Mother gorilla Kumili embrasses her newborn at the zoo in Leipzig, central German. The baby gorilla was born during the night between 10 and 11 March and its sex is still unknown. It’s the second gorilla baby born within four month in this monkey group. Read more

Twin polar bear cubs stand with their mother Giovanna in their enclosure at Tierpark Hellabrunn in Munich...Twin polar bear cubs stand with their mother Giovanna in their enclosure at Tierpark Hellabrunn in Munich, March 19, 2014.  The 14 week-old cubs, who made their first public appearance on Wednesday, have yet to be named.      REUTERS/Michael Dalder (GERMANY  - Tags: ANIMALS SOCIETY)

Michael Dalder/Reuters

Twin polar bear cubs stand with their mother Giovanna in their enclosure at Tierpark Hellabrunn in Munich. The 14-week-old cubs, who made their first public appearance on Wednesday, have yet to be named.

The Sumatra Orang-Utan Matra (R) holds h...The Sumatra Orang-Utan Matra (R) holds her one week old baby and smooches with her other daughter Jolie in the enclosure at the zoo Hellabrunn in Munich, southern Germany on February 7, 2014. The little Orang-Utan baby was born in the zoo on January 31, 2014 and hasn't been named yet.

Christof Stache/AFP

A Sumatran orangutan holds her one-week old baby and smooches with her other daughter Jolie in the enclosure at the Hellabrunn zoo in Munich, Germany. The baby was born on January 31 but has yet to be names Read more

Visitors walk through the holiday lights display "ZooLights" at the Lincoln Park Zoo in Chicago, Illinois...Visitors walk through the holiday lights display "ZooLights" at the Lincoln Park Zoo in Chicago, Illinois

Jim Young/Reuters

Visitors walk through the holiday lights display “ZooLights” at the Lincoln Park Zoo in Chicago, Illinois.

Gorillas with rugby balls

Ben Birchall/PA Wire

Komale, a Western Lowland Gorilla, inspects a rugby ball that has been placed into the enclosure at Bristol Zoo as part of its enrichment programme.

Luka, almost two-year-old male polar bear, swims in his new home at the zoo in Wuppertal, Germany. He was born in the Netherlands and is meant to be the play partner for female polar bear Anori who is the same age.

Roland Weihrauch/EPA

Luka, an almost two-year-old male polar bear, swims in his new home at the zoo in Wuppertal, Germany. Born in the Netherlands, Luka has moved to Germany to be a companion for female polar bear Anori, who is the same age.

Giraffes at the Dortmund zoo...epa03841925 A young giraffe tries to reach food with its tongue at the zoo in Dortmund, Germany, 29 August 2013. A second full grown giraffe stands next to it.  EPA/Jan-Philipp Strobel

Jan-Philipp Strobel/EPA

A young calf stands next to a full grown giraffe while trying to reach food at the zoo in Dortmund, Germany Read more

 An orangutan covers itself with a blanket during winter time at Rio de Janeiro Zoo in Brazil

Yasuyoshi Chibayasuyoshi/AFP/Getty Images

An orangutan covers itself with a blanket during winter time at Rio de Janeiro Zoo in Brazil