Khan, a five-year-old male White Bengal tiger, looks on inside an open-air cage at the Royev Ruchey zoo in Krasnoyarsk, Russia, October 21, 2016. (Photo by Ilya Naymushin/Reuters)

A man looks at the description of a sculpture depicting 17-year-old male chimpanzee Jaska, by Gillie and Mark, in London, Tuesday, September 20, 2022. (Photo by Vadim Ghirda/AP Photo)

An undated handout picture released on January 10, 2017 by the Issekinicho publishing house shows an inter- species sexual behaviour between a male Japanese macaque and female sika deer, in Yakushima Scientists revealed on January 10, 2017 the “highly unusual” behaviour of a male monkey filmed trying to have sеx with female deer in Japan – a rare case of inter- species nookie. (Photo by Editions Issekinicho/AFP Photo)

This huge male orangutan is having a right old laugh as he squints his eyes and shows his huge teeth. The orangutan, called Bimbo, was relaxing on a platform around 5m high in his enclosure when he broke out into a laugh. But his happy smile soon disappeared when another orangutan came over to see what was going on. Bimbo – the only male in the group of five apes at Leipzig Zoo, in Germany - appears to be laughing in much the same way as a human would. (Photo by Martina Radtke/Solent News)

A chimpanzee in the Osnabrück Zoo in Lower Saxony makes contact with a small zoo visitor sitting in front of a pane on September 1, 2020. The two males Lobo and Lome moved from Leipzig Zoo to Osnabrück Zoo to strengthen the social structure of the existing group. (Photo by Friso Gentsch/dpa)

The Greater Sage-Grouse is certainly a formidable-looking bird. Being the largest grouse in North America and having tail feathers, which look like giant spikes, make for a ferocious sight. These birds are well known for their complicated courtship rituals, in which the males perform a special “strutting display” to attract the females. Another distinct feature of the Greater Sage-Grouse is two large yellow throat sacs (gular sacs), which are inflated by the males during the courtship display. Unlike pelicans, whose gular sacs are used to store fish while hunting, the throat sacks of the Greater Sage-Grouse are merely for display.

Buyan, a male Siberian brown bear, is given a shower by a zoo employee in his enclosure at the Royev Ruchey zoo in Russia's Siberian city of Krasnoyarsk June 24, 2014. The Siberian city has been experiencing temperatures of around 30 degrees Celsius over the last week. (Photo by Ilya Naymushin/Reuters)

An officer of the Afghan border police throws an assault rifle to a policeman participating in a military exercise on the outskirts of Herat, Afghanistan, Monday, September 7, 2015. Twelve female and seventy male border police personnel participated in the military exercise near the border with Iran in Herat province. (Photo by Hoshang Hashimi/AP Photo)