Solvin Zankl / Black backed jackal (Canis mesomelas) attacking Cape fur seal (Arctocephalus pusillus) pup, Sperrgebiet National Park, Namibia, December. Sequence 3/6

Sandra Bartocha / Silver birch (Betula pendula) and Scots pine (Pinus sylvestris) trunks in snow, Muritz-National Park, Germany, January.

Christophe Courteau / Mountain Gorilla (Gorilla beringei) dominant male silver back sitting amongst vegetation. 2700 metres above sea level in Volcanoes National Park, Rwanda. short dry season, February

Bernard Castelein / Birch (Betula pendula) and Scot's pine (Pinus sylvestris) trees at dawn. Klein Schietveld, Brasschaat, Belgium. September 2019.

Nigel Cattlin / Dusky birch sawfly (Craesus latitarsus) larvae on the leaves on a young silver birch tree (Betula pendula), Berkshire, September

Nigel Cattlin / Dusky birch sawfly (Craesus latitarsus) larvae on the leaves on a young silver birch tree (Betula pendula) Berkshire, September

Dave Bevan / European eel (Anguilla anguilla) elver trying to migrate up a rock face, before slipping back, Ceredigion, Wales, UK, July.

Mark Taylor / RF - Playful Silver tabby kitten rolling on back (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF - Silver tabby cat, Freya, age 5 months, rolling on her back. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF - Silver tabby Persian-cross kitten arching back in playful confrontation. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / Silver tabby cat, Blaze, age 10 months, standing up.

Mark Taylor / Silver tabby cat, Freya, age 5 months, rolling on her back.

Mark Taylor / Silver tabby kitten, Freya, 4 months, with clasped paws.

Mark Taylor / Silver tabby kitten, Freya, age 7 weeks, with raised paws.

Mark Taylor / Silver tabby Persian-cross kitten with raised paws.

Mark Taylor / Silver tabby Persian-cross kitten arching back in playful confrontation.

Mark Taylor / Silver tabby kitten, Freya, 3 months, sitting with grasping paws as if catching something.

Mark Taylor / Mackerel Silver Tabby cat, sitting and looking up.

Stephen Dalton / Silver washed fritillary (Argynnis paphia) in flight, Sussex, England, UK, July.

SCOTLAND: The Big Picture / Silver birch (Betula pendula) tree silhouetted against night sky, Glenfeshie, Cairngorms National Park, Scotland, UK, December.

Mark Taylor / Silver tabby cat, Loki, age 7 months, rolling on his back.

Mark Taylor / Silver tabby cat, Loki, age 7 months, lying on his back and looking up.

Neil Aldridge / Black-backed Jackal (Canis mesomelas) pup walking back to its den, Mashatu Game Reserve, Tuli, Botswana.

Roger Powell / Great cormorant (Phalacrocorax carbo) catching and attempting to eat a European eel (Anguilla anguilla) on the side of a tidal pool. Druidge Pools Nature Reserve, Northumberland, England, UK. August....

Cyril Ruoso / Western lowland gorilla (Gorilla gorilla gorilla) 'Tonga' a 15 years old silver back gorilla. PPG reintroduction project managed by Aspinall Foundation, Bateke Plateau National Park, Gabon, June 201...

Cyril Ruoso / Western lowland gorilla (Gorilla gorilla gorilla) 'Tonga' a 15 years old silver back gorilla, at forest edge / savannah. PPG reintroduction project managed by Aspinall Foundation, Bateke Plateau Nati...

Juan Carlos Munoz / Black-backed jackal (Canis mesomelas) rear view of animal looking alert, Namib Naukluft National Park, Namibia

Georgette Douwma / Big-eye or Goggle-eye (Priacanthus hamrur) with some changing colour from silver to bright red and back again. Andaman Sea, Thailand.

Eric Baccega / Eastern lowland gorilla (Gorilla beringei graueri), silver back dominant male, feeding in the marshes, Kahuzi Biega NP, Democratic Republic of Congo.

Eric Baccega / Angolan giraffes (Giraffa camelopardalis angolensis) and Black backed jackal (Canis mesomelas) reflecting in waterhole at sunset, Okaukuejo, Etosha National Park, Namibia, Africa

Mark Taylor / Silver tabby kitten, Loki, age 3 months, lying on his back.

Mark Taylor / Silver tabby kitten, Loki, 11 weeks, standing up on his hind legs.

Mark Taylor / Silver tabby kitten, Loki, 11 weeks, standing on haunches.

Mark Taylor / Silver tabby kitten, Loki, 11 weeks, standing with paws raised.

Mark Taylor / RF- Silver tabby kitten, Loki, 11 weeks, standing on hind legs like a meerkat with front paws hanging. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF- Silver tabby kitten, Loki, 11 weeks, lying on his back. (This image may be licensed either as rights managed or royalty free.)

Jabruson Motion / Close up of the silver hair on the back of a male Eastern lowland gorilla (Gorilla beringei graueri) 'Chimanuka,' Kahuzi-Biega National Park, South Kivu, Democratic Republic of Congo.

Jabruson Motion / Close up of the silver hair on the back of a male Eastern lowland gorilla (Gorilla beringei graueri) 'Chimanuka,' Kahuzi-Biega National Park, South Kivu, Democratic Republic of Congo.

SCOTLAND: The Big Picture / Silver birch (Betula pendula) tree backlit, with raindrops on branches, Scotland, UK, December.

Charlie Summers / Black-backed Jackal (Canis mesomelas) fighting White-backed vultures (Gyps africanus) whilst scavenging Cape buffalo carcass hidden in the grass. Tarangire National Park, Tanzania

Graham Eaton / Black-backed jackal (Canis mesomelas) walking through scrub in early morning light, Karoo, South Africa.

Denis-Huot / Leopard (Panthera pardus) female carrying cub, followed by Black-backed jackals (Canis mesomelas) Masai-Mara game reserve, Kenya.

Robin Chittenden / Silver-beaked tanager (Ramphocelus carbo) perched, Trinidad and Tobago.

Mark Taylor / Maine Coon kitten, 8 weeks, lying on its back, looking up in a playful manner.

Fiona Rogers / Silvered / silver-leaf langur (Trachypithecus cristatus) group sitting on a branch. Bako National Park, Sarawak, Borneo, Malaysia.

Anup Shah / Silvered / silver-leaf langur (Trachypithecus cristatus) male head and shoulders portrait. Bako National Park, Sarawak, Borneo, Malaysia.

Anup Shah / Black-backed jackals (Canis mesomelas) feeding on a wildebeest carcass. Masai Mara National Reserve, Kenya. Taken with remote wide angle camera.

Tui De Roy / Australian Brush-tailed Possum (Trichosurus vulpecula) invasive species, adult with young perched on back. Golden Bay, South Island, New Zealand.