Panda cub Bao Bao plays in the Smithsonian National Zoological Park on January 6, 2014 in Washington, DC.
Famous panda cubs —
Panda cub Bao Bao plays in the Smithsonian National Zoological Park on January 6, 2014 in Washington, DC.
Chip Somodevilla/Getty
Triplet panda cubs rest in an incubator at the Chimelong Safari Park on August 12, 2014. The cubs, which weighed 83 grams, 90 grams, and 122 grams, respectively, at birth, are thought to be the only living panda triplets in the world.
Famous panda cubs —
Triplet panda cubs rest in an incubator at the Chimelong Safari Park on August 12, 2014. The cubs, which weighed 83 grams, 90 grams, and 122 grams, respectively, at birth, are thought to be the only living panda triplets in the world.
AP Photo
Seven-month-old panda Xing Bao explores his new enclosure at the Zoo Aquarium in Madrid on April 9, 2014.
Famous panda cubs —
Seven-month-old panda Xing Bao explores his new enclosure at the Zoo Aquarium in Madrid on April 9, 2014.
Gerard Julien/AFP/Getty
Six month old giant panda cub Long Long eats bamboo in Chimelong Safari Park in Guangzhou in February 16, 2014.
Famous panda cubs —
Six month old giant panda cub Long Long eats bamboo in Chimelong Safari Park in Guangzhou in February 16, 2014.
STR/AFP/Getty
Researchers place new-born panda cubs on a crib on September 23, 2013 at the Chengdu Giant Panda Breeding Center in China's Sichuan province.
Famous panda cubs —
Researchers place new-born panda cubs on a crib on September 23, 2013 at the Chengdu Giant Panda Breeding Center in China's Sichuan province.
STR/AFP/Getty
A keeper tucks in a group of panda cubs for a nap at the Chengdu Giant Panda Breeding Center on September 26, 2011.
Famous panda cubs —
A keeper tucks in a group of panda cubs for a nap at the Chengdu Giant Panda Breeding Center on September 26, 2011.
STR/AFP/Getty
A carer looks after twin panda cubs in China's Sichuan province on October 24, 2008.
Famous panda cubs —
A carer looks after twin panda cubs in China's Sichuan province on October 24, 2008.
China Photos/Getty Image