Almost two years old male baby orang-utan Dalai looks on in the zoo in Dresden, Germany, 30 March 2017. Dalai was born to mother Daisy in June 2016. (Photo by Filip Singer/EPA)

Donny Golden shares a laugh with dancers from the Irish American Society during the 250th annual St. Patrick's Day parade March 17, 2011 in New York City. The parade honors the patron saint of Ireland and marched for the first time in the U.S. on March 17, 1762, fourteen years before the Declaration of Independence.

A Banksy decorated truck entitled “Laugh now but one day we'll be in charge” is displayed for sale on October 6, 2011 in London, England. The Volvo FL6 lorry was decorated by British street artist Banksy for a millennium party for Turbozone, pyrotechnic touring circus. It will be offered for auction in London this month. (Photo by Peter Macdiarmid/Getty Images)

Two Red Deer stags stand in the early morning mist in Richmond Park on October 15, 2011 in London, England. Autumn sees the start of the “Rutting” season where the large Red Deer stags can be heard roaring and barking in an attempt to attract females known as bucks. The larger males can also be seen clashing antlers with rival males. (Photo by Dan Kitwood/Getty Images)

A photographer in Somerset, South West England captured the mating rituals of toads as several males attempt to mate with one female all at once. (Photo by John Waters/NPL)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

An Oriental Garden Lizard sits on a tree in Gauhati, India, Tuesday, April 16, 2019. During the breeding season, the male lizard's head and throat turn a bright color. (Photo by Anupam Nath/AP Photo)