Danny Green / Japanese crane (Grus japonensis) displaying, wings in heart shape, Hokkaido, Japan, February

Chris Newbert / Feather Duster Worm (Sabellastarte sp) in the shape of a heart, 40 feet deep, Solomon Islands

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

Frederique Olivier / Panning shot from an Emperor penguin (Aptenodytes forsteri) to a chick looking around and calling, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chick calling, with a heart shaped patch on its chest, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chick with a heart shaped patch on its chest approaching an adult, calling, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chick walking, with a heart shaped patch on its chest, Adelie Land, Antarctica, January.

Ingo Arndt / Aerial view of Hardy Reef, Great Barrier Reef, Queensland, Australia, December 2010.

Franco Banfi / Love locks on a bridge in Irkutsk, Lake Baikal, Siberia, Russia.

SCOTLAND: The Big Picture / Whooper swan (Cygnus cygnus) pair on loch in heart shape, Cairngorms National Park, Scotland, UK, November.

Albert Lleal / Heart Urchin (Echinocardium sp) spines, magnified 150 times, Spain

Bence Mate / Leaf cutter ants (Atta sp) carrying plant matter, Costa Rica.

Solvin Zankl / Green algae (Ulva nematoidea) on white background, from Swakopmund, Namibia, Africa, South Atlantic, April. Preserved specimen.

Kevin Schafer / Frozen gas bubbles beneath surface of frozen lake with snow in the shape of a heart, Abraham Lake, Canadian Rockies, Alberta, Canada

Pascal Pittorino / Heart formed by erosion into the rock, Calanches of Piana, Gulf of Porto, Parc Naturel Regional de Corse / Corsica Natural Regional Park, Corsica Island, France, September 2009.

Alex Hyde / Heart-shaped leaf of Alpine Cyclamen (Cyclamen purpurascens). Plitvice Lakes National Park, Croatia. January.

Alex Hyde / Heart-shaped leaf of Alpine Cyclamen {Cyclamen purpurascens}. Plitvice Lakes National Park, Croatia. January.

Staffan Widstrand / Heart-shaped lichen on rock, Laponia Circuit, along the Padjelantaleden trail, Padjelanta National Park and Sarek National Park, Norrbotten, Lapland, Sweden.

Mark Taylor / Two white doves on pink background looking at each other.

Pal Hermansen / Heart shape in grass near farm, with Reindeer crossing sign, Telemark, Norway, August 2012.

Mark Taylor / Black-and-white rabbit, Bandit, with soft heart surround.

Juergen Freund / Aerial view of Hardy Reef, Great Barrier Reef, August 2011

Andrew Parkinson / 2020VISION / Murmuration of Common starlings (Sturnus vulgaris) forming into a heart shape above Aberystwyth pier prior to roosting, Ceredigion, Wales, UK, December

Juergen Freund / Heart urchin (Echinocardium sp) of the family Loveniidae. These sea urchins are named for their shape. Lembeh Strait, North Sulawesi, Indonesia

Ross Hoddinott / 2020VISION / Heart shape and initials engraved into the bark of tree, Beacon Hill Country Park, The National Forest, Leicestershire, UK. November

Ross Hoddinott / 2020VISION / Heart shape and initials engraved into the bark of tree, Beacon Hill Country Park, The National Forest, Leicestershire, UK. November. 2020VISION Book Plate.

Sue Daly / Elegant anemone (Sagartia elegans) with tentacles open in the shape of a heart, Sark, British Channel Islands, UK

Jose B. Ruiz / European bee eaters (Merops apiaster) on branch. Seville, Spain

Juergen Freund / Aerial view of the Heart Reef, Hardy reef, Great Barrier Reef, Queensland, Australia

Tui De Roy / Great Frigatebird (Fregata minor) male in courtship display with extended gular pouch, Darwin Bay, Genovesa Tower Island, Galapagos Islands, Ecuador

Duncan Usher / Heart shaped hole in volcanic rock, Cyprus

Jouan & Rius / Greater flamingo (Phoenicopterus roseus) pair touching beaks in courtship display at sunset, as flock performs courtship dance behind them, Camargue, France, March.

Oriol Alamany / Whooper swans (Cygnus cygnus) pair engaged in courtship as snow falls, Myvatn lake, Iceland, March.

Chris Mattison / Fork-leafed sundew (Drosera binata) unfurling leaf of a cultivated plant, originally from Australia.

Staffan Widstrand / Wild Wonders of China / Yan Xiu Yan with photographer Deng, Shi Ma Jiao harbour, Guangdong province, China November 2015.

Remi Masson / Aerial view of a Karst spring, Marais de Lavours Reserve, Ain, Alps, France, November.

Ross Hoddinott / A heart shape made in moss on a beech tree, autumn at Bolderwood, The New Forest, Hampshire, UK. November.

Andy Trowbridge / Australasian crested grebe (Podiceps cristatus australis) pair in courtship display, portrait. Lake Camp, Ashburton Lakes, Canterbury, New Zealand. August.