Morley Read / Slow motion clip of a Linnaeus' sipo snake (Chironius exoletus) with open mouth, part of threat display, Amazon rainforest, Orellana Province, Ecuador. (non-ex)

Morley Read / Parrot snake (Leptophis ahaetulla) threat display, Amazon rainforest, Orellana Province, Ecuador. (non-ex)

Bence Mate / European rabbits (Oryctolagus cuniculus) fighting each other, Kiskunsag National Park, Hungary. June. Winner, 2019 Cadiz Photo Nature Competition.

Diane McAllister / Polar bears (Ursus maritimus) fighting in water. Beaufort Sea , Kaktovik, Alaska, USA. Highly commended in the Polar Passion category of the Nature's Best Photography Competition 2019.

Phil Savoie / Blue tit (Cyanistes caeruleus) bringing Crab spider (Misumena vatia) prey to nest, Monmouthshire Wales, UK, May.

Alex Mustard / Dugong (Dugong dugon) male and juvenile Golden trevally (Gnathanodon speciosus) swimming over Seagrass (Halophila stipulacea) meadow. Marsa Nabaa, Marsa Alam, Egypt.

David Tipling / Common European adder (Vipera berus) two males fighting over a female. Holt, North Norfolk, England, UK. April

David Tipling / Common European adder (Vipera berus) two males fighting over a female, Holt, North Norfolk, England, UK. April

David Tipling / Common European adder (Vipera berus) two males fighting over a female, Holt, North Norfolk, England, UK. April.

Jack Dykinga / Burrowing owl (Athene cunicularia) female and ten chicks aged a few weeks. Marana, Arizona, USA. May.

Gary Bell/ Oceanwide / Coconut Palm (Cocos nucifera) fruit germinating on tropical beach, Keeling Islands, Australia

Gary Bell/ Oceanwide / Coconut Palm (Cocos nucifera) fruit germinating on tropical beach, Keeling Islands, Australia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning mouth of Tomato Grouper (Cephalopholis sonnerati), Great Barrier Reef, Australia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning mouth of Tomato Grouper (Cephalopholis sonnerati), Great Barrier Reef, Australia

Gary Bell/ Oceanwide / Black-spot Goatfish (Parupeneus signatus) and Goldlined Seabream (Rhabdosargus sarba) school, Solitary Islands Marine Park, New South Wales, Australia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning female Stocky Anthias (Pseudanthias hypselosoma), Tulamben, Bali, Indonesia

Gary Bell/ Oceanwide / Whitemouth Moray (Gymnothorax meleagris) being cleaned by Cleaner Wrasse (Labroides sp) juvenile, Christmas Island, Australia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning Yellow-edged Moray (Gymnothorax flavimarginatus), Tulamben, Bali, Indonesia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning Honeycomb Moray Eel (Gymnothorax favagineus), Tulamben, Bali, Indonesia

Gary Bell/ Oceanwide / Scarlet Cleaner Shrimp (Lysmata amboinensis) cleaning mouth of Goldbelly Cardinalfish (Apogon apogonides), Tulamben, Bali, Indonesia

Doug Gimesy / Little blue penguin (Eudyptula minor), two standing on rocks at night, silhouetted against Melbourne city lights. St Kilda breakwater, Victoria, Australia. December 2016. COP26 Countdown Photo Competi...

Staffan Widstrand / African bush elephant, (Loxodonta africana) two head to head playing, Zimanga Private Nature Reserve, KwaZulu Natal, South Africa

Ingo Arndt / Close-up of a Guanaco (Lama guanicoe) feeding, Torres del Paine National Park, Patagonia, Chile, December.

Matthew Maran / Red fox (Vulpes vulpes) dog interacting with a vixen in an urban garden. North London, UK. June.

Matthew Maran / Red fox (Vulpes vulpes) dog interacting with a vixen in an urban garden. North London, UK. July.

Alex Mustard / Two female Common seahorses (Hippocampus kuda) fighting over territory on the seabed. The brief fight was preceeded by a ritualised, synchronised parade. Bitung, North Sulawesi, Indonesia. Lembeh Stra...

Tony Wu / View down the throat of a male Zoarchias major eelpout (Zoarchias major) that has opened its mouth during a confrontation with another male. Yamaguchi Prefecture, Japan. Pacific Ocean.

Tony Wu / Two male Zoarchias major eelpouts (Zoarchias major) engaged in a mouth-to-mouth confrontation. Yamaguchi Prefecture, Japan, Pacific Ocean.

Tony Wu / Zoarchias major eelpouts. (Zoarchias major) The orange individual is female, the one in the hole is male. The female has approached the male, curled around him, attempting to dislodge the male from th...

Tony Wu / Zoarchias major eelpout (Zoarchias major) with her mouth wide open. Yamaguchi Prefecture, Japan, Pacific Ocean.

Nick Upton / Marbled white butterflies (Melanargia galathea) nectaring on a clump of Greater knapweed flowers (Centaurea scabiosa) in a chalk grassland meadow, Wiltshire, England, UK, June.

Nigel Cattlin / Gardeners delight, Cherry tomato seedling just germinated with cotyledons above the soil

Nigel Cattlin / Gardeners delight, Cherry tomato seedling just germinated with cotyledons above the soil

Nigel Cattlin / Gardeners delight, Cherry tomato seedling just germinated with cotyledons above the soil

John Chan / Great horned owl (Bubo virginianus) chick watching for parents to return with food, Southern California, USA, June.

Francisco Marquez / Greater flamingo (Phoenicopterus ruber) flock silhouetted in wetland, Fuente de Piedra lagoon, Malaga, Spain. August.

Andy Rouse / Sally lightfoot crab, (Grapsus grapsus), feeding on marine iguana parasites and dead skin, Galapagos

Nick Hawkins / European green crab (Carcinus maenas), an invasive species in North America, Kejimkujik Seaside National Park, Nova Scotia, Canada. July.

Nick Hawkins / Head of a North Atlantic right whale (Eubalaena glacialis) showing callosities, patches of roughened skin that are unique to each whale. Gulf of Saint Lawrence, Canada. IUCN Status: Endangered. August

Ben Gillett / Slow motion clip of a female Appaloosa horse grooming a male, Bristol, England, UK, May.

John Chan / Two male Southern Pacific rattlesnakes (Crotalus oreganus helleri) fighting during mating season. This behaviour is known as a "combat dance", and is used to determine dominance and the right to mate...

Mary McDonald / Adult Mountain gorilla (Gorilla beringei beringei) holding baby, Hirwa group, Volcanoes National Park, Rwanda

SCOTLAND: The Big Picture / Grey seal (Halichoerus grypus) using freshwater pools along the shore line and in the adjacent fields as place to learn to swim, Orkney, Scotland, UK, April.

Oscar Dewhurst / Great bittern (Botaurus stellaris) head and neck, looking up through reeds. Suffolk, UK. November.

Oscar Dewhurst / Great bittern (Botaurus stellaris) portrait. Suffolk, UK. November.

Bence Mate / African wild dogs (Lycaon pictus) juveniles playing with the leg of an impala, trying to drag it in three different directions. Mkuze, South Africa. Commended in Glanzlichter photo competition 2020.

Steven David Miller / Emu (Dromaius novaehollandiae) juvenile with beak open to catch a leaf, Cleland Wildlife Park, South Australia, March. Captive.

Marie Read / Wood Ducks (Aix sponsa), females behave aggressively toward a male (second from right) that is trying to join them on a floating log, autumn, New York, USA, October.

Marie Read / Canada geese (Branta canadensis) two during territorial fight in early spring, Ithaca. New York, USA

Marie Read / American avocets (Recurvirostra americana) two during aggressive (territorial) encounter, Bear River Migratory Bird Refuge, Utah, USA, May.

David Pattyn / Great white egret (Egretta Alba) preening its feathers, Valkenhorst Nature Reserve, Valkenswaard, The Netherlands, July

David Pattyn / Alpine ibex (Capra ibex) adult males fighting in alpine landscape, Valsavarenche, Gran Paradiso National Park, Aosta Valley, Italy, May

TJ Rich / Four chocolate working cocker spaniels on wall. Mother and offspring. Monmouth, Monmouthshire, Wales

David Gallan / Two Southern right whales (Eubalaena australis) playing in shallows, taken with drone, Tathra Beach, New South Wales, Australia, August.

Gary Bell/ Oceanwide / Clown Anemonefish (Amphiprion ocellaris) in sea anemone, Australia

Gary Bell/ Oceanwide / Pink Anemonefish (Amphiprion perideraion) in sea anemone, Great Barrier Reef, Australia

Karine Aigner / Cuban parakeets (Psittacara euops) preening each other, Bermejas, Cuba. Endemic.

Markus Varesvuo / Jay (Garrulus glandarius), two fighting in mid-air with another observing. Norway. October.

Markus Varesvuo / Jay (Garrulus glandarius), two fighting in mid-air with another observing. Norway. October.

Karine Aigner / Cuban parakeet (Psittacara euops) preening, Bermejas, Cuba. Endemic.

George Sanker / Arctic tern (Sterna paradisaea), two fighting in mid-air. Machias Seal Island, New Brunswick / Maine, Canada / USA. July.

Eric Baccega / Coalition of two African male lions (Panthera leo) resting on the banks of the Luangwa river, dry season, South Luangwa National Park, Zambia

Eric Baccega / Lioness (Panthera leo), aggressively rebuffing male lion banks of the Luangwa river, South Luangwa National Park, Zambia

John Chan / Juvenile California least tern (Sternula antillarum browni) begging for food from a decoy, used to attract breeding pairs to deserted nest sites, Huntington Beach, California, USA, June.

John Chan / California least tern chick (Sternula antillarum browni) falling over as it runs towards its parent returning to nest site, Huntington Beach, California, USA, June.

John Chan / Juvenile Yellow-crowned night heron (Nyctanassa violacea)predating a twig, learning stalking and hunting skills, Southern California, USA, July.

John Chan / Juvenile Great blue heron (Ardea herodias) predating a twig , learning stalking and hunting skills, Southern California, USA, July.

John Chan / Great blue heron (Ardea herodias) chick begging to be fed, Southern California, USA, April.

Lorraine Bennery / Red-bellied lemur (Eulemur rubriventer) huddling together in tree branches. Anjozorobe Special Reserve, Madagascar. Vulnerable species, endemic.

Staffan Widstrand / Wild Wonders of China / Pere David's deer / Milu (Elaphurus davidianus), two stags testing their strength in Hubei Tian'ezhou Milu National Nature Reserve, Shishou, Hubei, China

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two adults brooding chicks. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two adults brooding chicks. One chick exhibiting aggression towards other. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two adults with chicks aged six to eight weeks. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two chicks aged six to eight weeks brooding on parents' feet, one vocalising. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two chicks aged six to eight weeks huddling together. Atka Bay, Antarctica. September.

Anup Shah / Vervet monkey (Cercopithecus aethiops) male scratching itself - remote camera . Masai Mara National Reserve, Kenya.

Guy Edwardes / Mozambique spitting cobra (Naja mossambica) spitting venom. Kruger, South Africa. Controlled conditions.

Pedro Narra / Red fox (Vulpes vulpes) vixen grooming cub, Sado Estuary, Portugal. May

Daniel Heuclin / Whistling heron (Syrigma sibilatrix sibilatrix), southern subspecies, native to Bolivia. Captive.

Jack Dykinga / Burrowing owl (Athene cunicularia) at sunset, standing on one leg, Marana, Sonoran Desert, Arizona, USA. October.

Jack Dykinga / Burrowing owl (Athene cunicularia) with head turned to one side, Marana, Sonoran Desert, Arizona, USA. October.

Paul Hobson / Parrot snake (Leptophis ahaetulla) in aggressive pose with mouth open. Costa Rica.

Paul Hobson / Red fox (Vulpes vulpes), two cubs play fighting. Sheffield, England, UK. May.

SCOTLAND: The Big Picture / Red deer (Cervus elaphus) stag in upland landscape. Lochcarron, Highlands, Scotland, UK.

Pal Hermansen / Brown bear (Ursus arctos), two showing aggression at night. Finland. August.

David Perpinan / Group of Griffon vultures (Gyps fulvus) fighting to feed on a dead lamb. Cuenca, Spain, August.

Ann & Steve Toon / Impala (Aepyceros melampus) allo-grooming, iMfolozi game reserve, KwaZulu-Natal, South Africa, August

Christophe Courteau / Mountain gorilla (Gorilla beringei beringei) blackback, juvenile male demonstrating power. Volcanoes National Park, Rwanda.

Christophe Courteau / Mountain gorilla (Gorilla beringei beringei) blackback, juvenile male demonstrating power. Volcanoes National Park, Rwanda.

Andy Rouse / White-necked Jacobin hummingbirds (Florisuga mellivora) fighting, Tobago Small repro only

Kerstin Hinze / Two Black-bellied hamsters (Cricetus cricetus) fighting, Vienna, Austria, October.

Franco Banfi / Sperm whale (Physeter macrocephalus) young male trying to copulate with a female. The calf of the female was in the way so the male is trying to chase it away. Dominica.

Tui De Roy / Galapagos lava lizard (Microlophus albemarlensis) sitting on Marine iguana (Amblyrhynchus cristatus) Punta Espinosa, Fernandina Island, Galapgos.

Tui De Roy / San Cristobal giant tortoises (Chelonoidis chatamensis), fighting, Galapaguera, San Cristobal Island, Galapagos