Ingo Arndt / Tisza mayflies (Palingania longicauda) swarming, River Tisza, Hungary, June

Mark Hamblin / 2020VISION / Two male Black grouse (Tetrao tetrix) fighting at lek site, with mountain backdrop, Cairngorms NP, Scotland, UK, April 2010

Ramon Navarro / Male European bee eater (Merops apiaster) offering insect to female as part of a courtship display, before mating, Seville, Spain, May.

Mark Hamblin / 2020VISION / Two male Common frogs (Rana temporaria) trying to mate with a female in a garden pond, Warwickshire, England, March.

Alex Mustard / Rock beauty angelfish (Holacanthus tricolor) pair at dusk performing their courtship dance with the larger male circling the female, Georgetown, Grand Cayman, Cayman Islands, British West Indies. Cari...

Ross Hoddinott / 2020VISION / Common blue damselfly {Enallagma cyathigerum}, mating pair, Little Bradley Ponds, Devon, UK. July. 2020VISION Book Plate.

Ross Hoddinott / 2020VISION / Common blue damselfly {Enallagma cyathigerum}, mating pair, Little Bradley Ponds, Devon, UK. July

Daniel Heuclin / Pyrenean mountain newt / brook salamander (Calotriton / Euproctus asper) mating pair, captive, from Pyreneen mountains, France and Spain, near threatened

Juergen Freund / Green turtles (Chelonia mydas) mating over coral reef, Sipadan Island, Sabah, Malaysia, June, Endangered species

Ben Hall / 2020VISION / Irish Damselfly (Coenagrion lunulatum) pair mating, Montiagh's Moss, County Antrim, Northern Ireland, June. 2020VISION Book Plate.

Hermann Brehm / Male Andean Cock-of-the-Rock (Rupicola peruvianus) displaying. Cock-of-the-Rock Lodge, Peru, August.

Hermann Brehm / Male Andean Cock-of-the-Rock (Rupicola peruvianus) displaying. Cock-of-the-Rock Lodge, Peru, August.