JIM CLARE / Buffon's / Great green macaw (Ara ambigua) adult pair at nest hole in Almendro tree, Costa Rica

JIM CLARE / Buffon's / Great green macaw (Ara ambigua) adult pair in nest hole in Almendro tree, Costa Rica

Jeff Vanuga / Gentoo Penguin (Pygoscelis papua) mating. Cuverville Island, Antarctica.

Denis-Huot / Masai Giraffe (Giraffa camelopardalis tippelskirchi) male and female (back). Masai-Mara Game Reserve, Kenya.

David Pattyn / Black necked grebe (Podiceps nigricollis) frontal view of pair mating, La Dombes lake area, France, April

Linda Pitkin / 2020VISION / Spiny spider crab (Maja brachydactyla / squinado) pair on rock covered with red algae, Lundy Island Marine Conservation Zone, Devon, England, UK, May.

Markus Varesvuo / Two Sparrowhawks (Accipiter nisus) immature male and female in flight, male on left, Falsterbo, Sweden. September.

Christophe Courteau / Pair of West African giraffes {Giraffe camelopardis peralta}. Male on right, female on left.

Andy Sands / Small emperor moth (Saturnia pavonia) male (bottom) and female with wings open showing eyespots on lichen covered twig, Captive, UK, April

Andy Sands / Small emperor moth (Saturnia pavonia) male below female both displaying eyespots on Gorse, Captive, UK, April

Steven Kazlowski / Killer WHale / Orca (Orcinus orca) bull and cow in Resurrection Bay, Kenai Fjords National Park, outside Seward, Alaska, May.

Cheryl-Samantha Owen / Green turtles (Chelonia mydas) pair mating near surface, Aldabra Atoll, Seychelles, Indian Ocean

Solvin Zankl / Common European toads (Bufo bufo) mating, with membranes closed over eyes for protection, Solling, Central Germany.

Roger Powell / Pair of European Bee-eater (Merops apiaster) on a bank above their nest hole in front of flowers. Note regurgitated pellets of insect remains. Alentejo, Portugal, April.

Roger Powell / European Bee-eater (Merops apiaster) with a bee landing on a branch by its mate. Alentejo, Portugal, May.

Roger Powell / European Bee-eater (Merops apiaster) courting a female by offering her a Small Copper butterfly (Lycaena phlaeas). Alentejo, Portugal, April.

Andy Rouse / 2020VISION / European Hares (Lepus europaeus) boxing, female on right. Wales, UK, June. Sequence 2 of 2. Did you know? A group of hares is known as a drove.

Andy Rouse / 2020VISION / European Hares (Lepus europaeus) boxing, female on right. Wales, UK, June. Sequence 1 of 2.

Andy Sands / Digger Wasp (Cerceris rybyensis) Female carrying two males attempting to displace one another to mate, West sussex, England, UK, July

LYNN M. STONE / Great Egrets (Ardea alba) preening their breeding plumage, at nest. Osceola County, Florida, USA, March.

Michel Poinsignon / Praying mantis (Mantis religiosa) pair on plant facing each other, Lorraine, France, September.

Michel Poinsignon / Mute swan (Cygnus olor) two adults on water in courtship display, Lorraine, France, January.

Mark Hamblin / 2020VISION / Pair of Common frogs (Rana temporaria) in garden pond, Warwickshire, England, UK, March

Andy Sands / Kingfisher (Alcedo atthis) male passing fish to female spring during courtship behaviour, Hertfordshire, England, UK, March. Sequence 2 of 6.

David Shale / Male and Female glass shrimps on Glass sponge (Hexactinellida) from coral seamount, SW Indian Ridge, Indian Ocean, December 2011

Erlend Haarberg / Bar-tailed godwit (Limosa lapponica) courtship display, male in flight, Finnmark, Norway, May

Rolf Nussbaumer / Black-necked stilt (Himantopus mexicanus) pair displaying, Dinero, Lake Corpus Christi, South Texas, USA.

Dave Watts / Mareeba rock wallaby (Petrogale mareeba) family, near Mareeba, Queensland, Australia, November

Ben Hall / Great crested grebes (Podiceps cristatus) performing their elaborate courtship ritual at dawn, Cheshire, UK November

Ben Hall / Great crested grebes (Podiceps cristatus) performing courtship ritual at dawn, Cheshire, UK April

Roland Seitre / Spix's Macaw (Cyanopsitta spixii) male and female pair, portrait, captive, critically endangered species, from Brazil

Ben Hall / Long tailed tits (Aegithalos caudatus) pair perched on pine branch in snowfall, Cheshire, UK March

Ben Hall / Shelducks (Tadorna tadorna) pair in flight at dusk, Lancashire, UK

Vladimir Medvedev / Whiskered Auklet (Aethia pygmaea) male and female courtship, Jonah's island, Sea of Okhotsk, Far East Russia, July .

Florian Möllers / Quinling Golden snub nosed monkey (Rhinopitecus roxellana qinlingensis), adult male (right) and female sitting on the ground close to each other. Zhouzhi Nature Reserve, Qinling Mountains, Shaanxi, Ch...

Ross Hoddinott / 2020VISION / Pair of mating soldier beetles (Rhagonycha fulva) on Common ragwort (Senecio jacobaea), Arne RSPB reserve, Dorset, England, UK, August. Did you know? In some areas this insect is called the “bloodsuck...

Marie Read / Western grebe (Aechmophorus occidentalis) pair swimming, with reflections, Bolsa Chica Ecological Reserve, California, USA, February

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...

Alex Mustard / Butter hamlet (Hypoplectrus unicolor) pair spawning at dusk, George Town, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Sergey Gorshkov / Willow grouse / ptarmigan (Lagopus lagopus) pair in flight, Agapa River, Taimyr Peninsula, Siberia, Russia

Luiz Claudio Marigo / Family of Southern coatis (Nasua nasua) in Atlantic Rainforest, Tijuca National Park, Rio de Janeiro City, Southeastern Brazil.

Markus Varesvuo / Smew, male and female (Mergus albellus) Finland May

Bert Willaert / Pair of mating Mouse Opossums (Marmosops cf. noctivagus) hanging from prehensile tail. Ecuador,

Bert Willaert / Amplectant pair of Natterjack Toads (Epidalea / Bufo calamita) with reflection in water. Belgium, Europe, July.

Mark Hamblin / 2020VISION / Greylag goose (Anser anser) pair on edge of loch, near nesting site, Scotland, UK, May 2010

John Abbott / Chilean rose / flame / fire / red-haired tarantula (Grammostola rosea) pair mating, female on left, male on right, from South America

Martin Gabriel / Stag Beetle (Lucanus cervus) pair mating. Bavaria, Germany, June.

Juan Carlos Munoz / Two White Tailed Sea Eagle (Haliaeetus albicilla) fighting in acrobatic flight as Raven (Corvus corax) looks on. Scandinavia, April. 5th, 2010 Euronatur Wildlife photographer competition.

Juan Carlos Munoz / Two White Tailed Sea Eagle (Haliaeetus albicilla) fighting in acrobatic flight as Raven (Corvus corax) looks on and a Herring Gull (Larus argentus) flies past. Scandinavia, April.

Konrad Wothe / Eclectus Parrot (Eclectus roratus) courtship behaviour in rainforest, Cape York Peninsula, North Queensland, Australia, captive

Konrad Wothe / Eclectus Parrot (Eclectus roratus) pair in rainforest, female on right, Cape York Peninsula, North Queensland, Australia, captive

Andrew Parkinson / 2020VISION / Great crested grebe (Podiceps cristatus) male mating with female who has shown her willingness to mate by lying on the nest site in front of a fishing platform, Derbyshire, UK, March, sequence 2/5

Andrew Parkinson / 2020VISION / Great crested grebe (Podiceps cristatus) pair of adults during part of their elaborate courtship ritual during the very last few rays of evening sunlight, Derbyshire, UK, March.

Andrew Parkinson / 2020VISION / Great crested grebe (Podiceps cristatus) pair of adults during part of their elaborate courtship ritual during the very last few rays of evening sunlight, Derbyshire, UK, March.

Kevin Schafer / Maleo (Macrocephalon maleo) pair on breeding ground, Sulawesi, Indonesia, Endangered

Fabrice Cahez / Great crested grebe (Podiceps cristatus) pair displaying, Vosges, France, March

Alex Mustard / 2020VISION / Two male Common cuttlefish (Sepia officinalis) compete for a female (on right) during courtship, Torbay, Devon, UK, May. 2020VISION Exhibition. 2020VISION Book Plate. Did you know? Cuttlefish have an...

Alex Mustard / 2020VISION / Pair of Common cuttlefish (Sepia officinalis), female in front of male, during spring spawning season, Babbacombe Bay, Torbay, Devon, UK, May

Alex Mustard / 2020VISION / Pair of Common cuttlefish (Sepia officinalis), female in foreground and male behind, note circular mating scars on female caused by the males suckers, Babbacombe Bay, Torbay, Devon, UK, May. Did you k...

Alex Mustard / 2020VISION / Pair of Skeleton shrimps (Caprella linearis) male on left, living on lightbulb tunicates. Bard Cave, Bressay, Shetland Islands, Scotland, UK, June

Steven Kazlowski / Walrus (Odobenus rosmarus) two young bulls, in waters along Spitsbergen and the northwestern coast of the Svalbard Archipelago, Norway, Arctic Ocean, July

Andrew Parkinson / Great crested grebes (Podiceps cristatus) a pair of adults perform their elaborate courtship dance. Derbyshire, UK, March.

Andrew Parkinson / Mute swans (Cygnus olor) pair of adults engaged in a courtship dance, Nottinghamshire, UK, February.

Ernie Janes / Silhouette of Red deer (Cervus elaphus) stag, hind and fawns at sunset, Norfolk, UK

Dave Watts / Eastern grey kangaroo (Macropus giganteus) family group, male, female and large joey, Tasmania, Australia, February

Sandesh Kadur / King cobra (Ophiophagus hannah) male and female courtship, Agumbe, Karnatka, India, captive

Anup Shah / Maasai ostrich male and female courting (Struthio camelus massaicus) Masai Mara National Reserve, Kenya

Anup Shah / Black backed jackal (Canis mesomelas) male grooming female, Masai Mara National Reserve, Kenya

Anup Shah / Lions mating (Panthera leo), Masai Mara National Reserve, Kenya

B&S Draker / Pipevine Swallowtail Butterflies (Battus philenor) pair mating close-up. Sinton, Corpus Christi, Coastal Bend, Texas, USA, June.

B&S Draker / Pipevine Swallowtail Butterfly (Battus philenor) pair mating. Sinton, Corpus Christi, Coastal Bend, Texas, USA, June.

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

George Sanker / Yellow-bellied Marmots (Marmota flaviventris) mating. Yellowstone National Park, Wyoming, USA, June.

Patricio Robles Gil / Pale-legged Hornero (Furnarius leucopus) male and female birds building their mud nest on a branch. Parana, Southern Brazil.

Mark Hamblin / 2020VISION / Red-throated diver (Gavia stellata) adult pair displaying on breeding loch, Flow Country, Highland, Scotland, UK, June. Did you know? The Flow Country of Caithness and Sutherland is home to the larges...

Mark Hamblin / 2020VISION / Black grouse (Tetrao tetrix) female at lek on heather moorland with two males displaying nearby, Cairngorms NP, Grampian, Scotland, UK, April

Klaus Echle / Red Deer (Cervus elaphus) stag and two females in snow-covered woodlands. Black Forest, Germany, January.

Andy Rouse / African Lion (Panthera leo) male lion greeting female and cubs, Notch from Disney African Cats film, Masai Mara GR, Kenya, February

Jeff Wilson / Emperor penguin (Aptenodytes forsteri) two adults in colony, Cape Crozier, Antarctica, November 2009. Taken on location for BBC series, Frozen Planet, Spring.

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

Terry Whittaker / 2020VISION / Young boy with the same birthday as male Osprey 5R watching the Manton Bay osprey pair (including 5R) from the Waderscrape hide, Lyndon Visitor Centre, Rutland Water, Rutland, UK, April 2011

Terry Whittaker / 2020VISION / Great crested grebe (Podiceps cristatus) pair displaying on water at dawn, Rutland Water, Rutland, UK, April. Photographer quote: 'During the Rutland Water 2020VISION iWitness I was really struggling...

Markus Varesvuo / Velvet Scoter (Melanitta fusca) female (foreground) and male on water. Finland, May. Magic Moments book plate, page 150.

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.

Terry Whittaker / 2020VISION / Konik horse (Equus caballus) pair interacting, wild herd in rewilding project, Wicken Fen, Cambridgeshire, UK, June 2011

Diane McAllister / Great blue heron (Ardea herodias) landing with branch for its mate, who is constructing their nest on a treetop. Venice Rookery, Florida, USA, January

Andy Rouse / Mountain Gorilla (Gorilla beringei) male and female after mating. Rwanda, Africa

Juergen Freund / Coral trout / Leopard coral grouper (Plectropomus leopardus) mating behaviour. Males approach the females and display with their bodies and fins. Misool, Raja Ampat, West Papua, Indonesia,

Peter Cairns / 2020VISION / Mute swan (Cygnus olor) pair on water in winter dawn mist, Loch Insh, Cairngorms NP, Highlands, Scotland UK, December

Peter Cairns / 2020VISION / Pair of Gannets (Morus bassanus) mutual preening, Bass Rock, Firth of Forth, Scotland, UK, June

Peter Cairns / 2020VISION / Pair of Gannets (Morus bassanus) mutual preening, Bass Rock, Firth of Forth, Scotland, UK, June. Photographer quote: 'I never get tired of watching gannets. This pair who momentarily lined up in perfe...

Juergen Freund / Mating pair of Green turtles (Chelonia mydas) in the reef shallows. Sipadan Island, Sabah, Malaysia. June

Juergen Freund / Mating Green turtles (Chelonia mydas) in the reef shallows. Sipadan Island, Sabah, Malaysia, June