A competitor calls with a shell at the German championships in Deer-Calling at the “Jagd & Hund” (hunting & dog) exhibition in Dortmund February 6, 2015. Competitors use specially designed instruments or ox horns to imitate the mating call of red deers. About 750 exhibitors will present their latest developments at the 34th “Jagd & Hund” exhibition, which runs from February 3 to February 8. (Photo by Ina Fassbender/Reuters)

In this image provided by the Pairi Daiza park, giant panda Hao Hao holds her newborn baby in her mouth at the park in Brugelette, Belgium, on Thursday, June 2, 2016. With the help of the Chinese government Hao Hao and her mate Xing Hui arrived in Belgium two years ago and Pairi Daiza adapted its park to build a bamboo forest for them. (Photo by Benoit Bouchez/Pairi Daiza via AP Photo)

In this handout image provided by Parks Australia, thousands of red crabs are seen walking in a drain on November 23, 2021 in Christmas Island. The annual migration of red crabs begins with first rains of the wet season on Christmas Island, usually around October or November. Millions of the red crabs make their way across the island to the ocean to mate and spawn. (Photo by Parks Australia via Getty Images)

The world’s largest public sauna has opened on a small island in the Arctic Circle and there’s room for you and about 100 of your closest mates.

The blue-footed booby (Sula nebouxii) is a marine bird in the family Sulidae, which includes ten species of long-winged seabirds. Blue-footed boobies belong to the genus Sula, which comprises six species of boobies. It is easily recognizable by its distinctive bright blue feet, which is a sexually selected trait. Males display their feet in an elaborate mating ritual by lifting their feet up and down while strutting before the female.

A male green anole lizard flares his throat fan in a backyard in Cary, North Carolina on April 27, 2021. This pink section is actually a thin flap of skin that hangs down below the green anole's throat. Anoles are renowned for their displays in which they do pushups, bob their heads up and down, and unfurl their colorful dewlaps. The male anole uses it for two primary purposes: to protect his territory and attract a mate. (Photo by Bob Karp/ZUMA Press Wire/Alamy Live News)

Combat between two male stag beetles, Italy, 2022. During the mating season, male stag beetles (Lucanus cervus) go into a frenzy, with lively but harmless clashes, in which bigger males often have the advantage over smaller ones due to their impressive mandibles. Longer larval development and genetic traits can increase the size of some individuals, but all saproxylic beetles are threatened by poor forest management, logging and dead wood removal to “clean” the forest. (Photo by Iacopo Nerozzi)

Kenyan photographer and art director Barbara Minishi (L) takes pictures of her room mate and fashion stylist Wambui Thimba (R) wearing a creation by a Kenyan fashion designer on the rooftop of their apartment in Nairobi, Kenya, on June 1, 2020. After their scheduled works was cancelled due to the spread of the COVID-19 coronavirus, Minishi and Thimba have started their own project called “the Kenya Fashion & Style Diary in 21 days” to showcase a Kenyan fashion brand everyday for 3 weeks on social networking services since May 22, 2020 by only shooting at their apartment. (Photo by Yasuyoshi Chiba/AFP Photo)