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

Stephen Dalton / Close up of a Cynara sp flower, UK.

Ben Cranke / Arctic Redpoll (Carduelis hornemanni) perched on frosty plant, Finland. February.

Alex Hyde / Stinging nettle (Urtica dioica) close up of stinging hairs, the silicified tips of the stinging hairs are brittle and snap off easily if the nettle is brushed. Focus stacked image. UK.

Doug Perrine / Flower Hat Jelly / Jellyfish (Olindias formosa), a rare hydromedusa with fluorescent tentacle tips. Endemic to Brazil, Argentina, and southern Japan.

Andy Sands / Red grouse (Lagopus lagopus scoticus) feeding on Heather tips in blizzard, Cairngorms, Scotland, UK

Pete Oxford / Kathiawari horse with alert inward-turned ears which meet at the tips. Pushkar camel and livestock fair, Pushkar, Rajasthan, India, October 2006

Michael & Patricia Fogden / Blue Poison Dart Frog (Dendrobates azureus) very tiny frog used by Indian tribes to poison tips of arrows, native to South America

Gerry Ellis / Blue Poison Dart Frog (Dendrobates azureus) secretes a fluid from its skin which is used by indigenous Indians to poison the tips of arrows, native to South America

Georgette Douwma / Common reef / Day octopus hunting for crustaceans and fish, enclosing coral head with arms and webs, using the arm tips to flush out prey into waiting suckers {Octopus cyaneus} Andaman Sea, Thailand

Heather Angel / Lily (Lilium lophophorum) flowers. Tepals fused at tips to protects floral parts from precipitation, slits allow access to pollinators. Mugecuo Scenic Area, Kangding, Sichuan Province, China. June.

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