Anup Shah / Southern plains grey langur / Hanuman langur (Semnopithecus dussumieri) females mounting to show dominance. Jodhpur, Rajasthan, India. March.

Anup Shah / Southern plains grey langur / Hanuman langurs (Semnopithecus dussumieri) mounting to show dominance. Jodhpur, Rajasthan, India. March.

Espen Bergersen / Male King Eider (Somateria spectabilis) mounting female prior to copulation. Batsfjord, Norway, March.

Anup Shah / African Elephant (Loxodonta africana) pair playing in river, Mara River, Masai Mara, Kenya

Ammonite / Male juvenile African lion (Panthera leo) mounting female whilst playing, footage taken at night using starlight camera technology, Moremi Game Reserve, Botswana.

Tui De Roy / Marine Iguana (Amblyrhynchus cristatus) male in breeding color mounting female, Santa Cruz Island, Ecuador

Walter Soestbergen / Tufted Duck (Aythya fuligula) drake mounting female, Utrecht, Netherlands

Bob Steele / Sage Grouse (Centrocercus urophasianus) male mounting female, Mono County, California

Richard Steel / European Roller (Coracias garrulus) pair mating, Hungary

Peter Hering / Eurasian Oystercatcher (Haematopus ostralegus) pair mating, Schleswig-Holstein, Germany

Marion Vollborn / Great Spotted Cuckoo (Clamator glandarius) pair mating, Castile-La Mancha, Spain

Christine Jung / American Black Vulture (Coragyps atratus) pair mating, Florida