Morley Read / Slow motion clip of a group of male Mallards (Anas platyrhynchos) competing violently to mate with a single female, Cornwall, England, UK, May 2018. (non-ex)

Gary Bell/ Oceanwide / Australian Giant Cuttlefish (Sepia apama) group gathered for mating, Whyalla, South Australia, Australia

Alex Mustard / Pair of Western clown anemonefish (Amphiprion ocellaris) spawning orange eggs on the rock beneath their Magnificent sea anemone (Heteractis magnifica) home on a coral reef. This photo shows the larger...

John Shaw / Black-browed albatross pair (Thalassarche melanophris) mutual grooming during copulation. New Island, Falkland Islands, November.

Edwin Giesbers / Seven spot ladybird (Coccinella septempunctata) pair mating on Mayweed (Anthemis sp) flower. Cyprus. April.

Edwin Giesbers / Seven spot ladybird (Coccinella septempunctata) pair mating on Mayweed (Anthemis sp) flower. Cyprus. April.

Marie Read / Black-necked stilts (Himantopus mexicanus) pair performing post-copulatory display (as copulation ends, the male slides off the female leaving his wings draped over her and crossing his bill with hers...

Nick Upton / Pair of White storks (Ciconia ciconia) mating on their nest, Knepp Castle Estate, Sussex, England, UK, April. This is the first recorded instance of White storks nesting in the UK for several hundreds...

John Chan / Male California least tern (Sternula antillarum browni) presenting fish offering to female during mating, Huntington Beach, California, USA, May.

Michael Hutchinson / Pair of Marsh fritillary butterflies (Euphydryas aurinia) mating, Devon, England, UK, June.

Michael Hutchinson / Close-up of a pair of Marsh fritillary butterflies (Euphydryas aurinia) mating, showing tips of abdomens, Devon, England, UK, June.

Michael Hutchinson / Close-up of a pair of Marsh fritillary butterflies (Euphydryas aurinia) mating, shot tilt downs, Devon, England, UK, June.