Alex Mustard / 2020VISION / Plumose anemones (Metridium senile) feeding on Moon jellyfish (Aurilia aurita), which they have captured. Loch Long, Argyll and Bute, Scotland, UK, June. Did you know? Loch Long was previously used as...

Tony Heald / Black rhinoceros (Diceros bicornis) male urine testing, flehmen reaction, Etosha National Park, Namibia October

Jose B. Ruiz / Spanish ibex male rut behaviour, testing female for oestrus (Capria pyrenaica) Sierra Gredos, Spain

Rolf Nussbaumer / Vermilion flycatcher fledgling testing wings {Pyrocephalus rubinus} Texas, USA.

Mark Jones / Komodo Dragon (Varanus komodoensis) large male testing ground for scent with specialized forked tongue, Komodo National Park, Komodo Island, Indonesia

IAN REDMOND / Forest Elephants with trunks raised among Giant Lobelia. Rwanda Parc National des Volcans

Anup Shah / Giraffe suckling with male testing urine of female Giraffa camelopardalis} Kenya

Terry Whittaker / 2020VISION / Researchers take skin sample from wing of Myotis bat probably a Daubenton's bat (Myotis daubentoni) for DNA testing, near Faversham, Kent, UK, September 2010

Terry Whittaker / 2020VISION / Researchers taking a skin sample from wing of a Myotis bat probably a Daubenton's bat (Myotis daubentoni) for DNA testing. Near Faversham, Kent, UK, September 2010

Terry Whittaker / 2020VISION / Researchers taking a skin sample from wing of a Myotis bat probably a Daubenton's bat (Myotis daubentoni) for DNA testing, near Faversham, Kent, UK, September 2010

Anup Shah / Celebes / Black crested macaque (Macaca nigra) juvenile putting a moth it has found in its mouth, Tangkoko National Park, Sulawesi, Indonesia.

Ann & Steve Toon / Warthog (Phacochoerus aethiopicus), boar urine testing sow, Mkhuze Game Reserve, South Africa

Radomir Jakubowski / Muskox (Ovibos moschatus) male flehmen testing female, Norway, September

Kristel Richard / Konik horses (Equus caballus) - wild Konik newborn colt running around, testing his legs, Millingerwaard nature reserve, Netherlands, April

Kristel Richard / Konik horses (Equus caballus) - wild Konik newborn colt running around, testing his legs, Millingerwaard nature reserve, Netherlands, April

Orsolya Haarberg / Two Chamois (Rupicapra rupicapra) in snow storm, one with tongue out, testing the air for female ovulation, Gran Paradiso National Park, Alps, Italy, November

Orsolya Haarberg / Alpine ibex (Capra ibex) ram testing the air to sense ovulation in females, flemen response, Gran Paradiso National Park, Alps, Italy, November

Orsolya Haarberg / Alpine ibex (Capra ibex) ram testing the air to sense ovulation in females, flemen response, Gran Paradiso National Park, Alps, Italy, November

Orsolya Haarberg / Alpine ibex (Capra ibex) ram testing the air to sense ovulation in females, flemen response, Gran Paradiso National Park, Alps, Italy, November

Ann & Steve Toon / African elephant (Loxodonta africana) bull urine testing female, Addo national park, Eastern Cape, South Africa, January

Kristel Richard / Feral domestic horses (Equus caballus) young filly running around, testing her legs, Blue Swallow Reserve, near Kaapsehoop, Mpumalanga province / Eastern Transvaal, South Africa, October 2010

Kristel Richard / Feral domestic horses (Equus caballus) young filly running around, testing her legs, Blue Swallow Reserve, near Kaapsehoop, Mpumalanga province / Eastern Transvaal, South Africa, October 2010

Kristel Richard / Feral domestic horses (Equus caballus) young filly running around, testing her legs, Blue Swallow Reserve, near Kaapsehoop, Mpumalanga province / Eastern Transvaal, South Africa, October 2010

Anup Shah / Lion pride (Panthera leo) testing a herd of Cape Buffalo (Syncerus cafer). Masai Mara National Reserve, Kenya, August 2009

Stephen Dalton / Ladybird spider (Eresus cinnaberinus) testing Woodlouse prey with its palps, Dorset, UK. In England this extremely rare spider has a habitat confined to a quarter acre patch in Dorset, and the male on...

Owen Newman / Red kangaroo {Macropus rufus} male testing to see if female is in oestrus, Sturt NP, New South Wales, Australia

Jeff Vanuga / Rocky Mountain Bighorn Sheep {Ovis canadensis} rams testing the air around a female, flehmen behaviour, Whiskey Basin, near Dubois, Wyoming, USA, November

Jeff Vanuga / Rocky Mountain Bighorn Sheep {Ovis canadensis} male testing the air, flehmen behaviour, Whiskey Basin Sheep Range. Wind River Mts, near Dubois, Wyoming, USA, November

Jeff Vanuga / Elk {Cervus canadensis} female trapped in a corale by the US Fish and Wildife Service and the Wyoming Game and Fish Department await testing by researchers for brucillosis disease. National Elk Refuge...

Jeff Vanuga / Elk {Cervus canadensis} trapped in a corale by the US Fish and Wildife Service and the Wyoming Game and Fish Department await testing by researchers for brucillosis disease. National Elk Refuge, Jacks...

Simon Colmer / European garden spider (Araneus diadematus) pair in courtship, male, smaller on right, testing signal line and approaching female, UK

Simon Colmer / European garden spider (Araneus diadematus) pair in courtship, male, smaller on right, testing signal line and approaching female, UK

Suzi Eszterhas / California Sea Lion (Zalophus californianus) in rehab center on EEG being tested for domoic acid poisoning from algal blooms, Marine Mammal Center, Marin county, California

Tony Heald / Male Lechwe {Kobus leche} testing urine of female, Moremi WR, Okavango delta, Botswana

Tony Heald / Male Lechwe {Kobus leche} testing urine of female, Moremi WR, Okavango delta, Botswana

Rolf Nussbaumer / Juvenile Harris's Hawks (Parabuteo unicinctus), 5 weeks, on nest testing wings, Mesquite tree, Willacy County, Rio Grande Valley, Texas, USA. May 2004

Richard Du Toit / Steenbok {Raphicerus campestris} male testing urine of female during courtship, Kruger NP, South Africa

LYNN M. STONE / Mustang foal testing the air (flehmen) {Equus caballus} Pryor Mountains, Montana, USA

Jean-Pierre Zwaenepoel / Wild gaur, male testing air around female {Bos gaurus} endangered, Bandhavgarh NP, Madhya Pradesh, India

Karl Ammann / Ba'ka pygmy in Cameroon, West Africa being tested for Ebola virus after eating infected gorilla meat. Close genetic correlation between humans and apes means that many of the same viruses and parasite...

Anup Shah / Masai giraffe {Giraffa camelopardalis tippelskirchi}males testing female for oestrus, Masai Mara reserve, Kenya

TOM MANGELSEN / Polar bear testing ice with with paw, Hudson Bay, Canada.

Jim Brandenburg / Timber Wolf (Canis lupus) testing lake ice, Minnesota

John Cancalosi / Spaninh ibex male in rut, testing air with tongue {Capra pyrenaica victoriae} Spain

Kit Rogers / Testing suction devise as a possible method for attaching equipment to whales. Sperm whales, Galapagos 1994

Kit Rogers / Testing suction device as a possible method for attaching tracking and research equipment to whales. Sperm whale in picture, Galapagos 1994.

Doug Allan / Polar bear males testing each other's strength, Churchill, Manitoba, Canada

Petra Wegner / Mixed Breed Dog (crossbred Pug-Dachshund) bitch investigating small apparatus for testing intelligence and providing food

Petra Wegner / Mixed Breed Dog (crossbred Pug-Dachshund) bitch licking small apparatus for testing intelligence and providing food

Petra Wegner / Mixed Breed Dog (crossbred Pug-Dachshund) bitch investigating small apparatus for testing intelligence and providing food

Petra Wegner / Mixed Breed Dog (crossbred Pug-Dachshund) bitch investigating small apparatus for testing intelligence and providing food

Tony Phelps / Oman Saw-scaled Viper (Echis omanensis) testing the air with tongue, Wasi Helo, UAE

Owen Newman / Male Red kangaroo testing to see if female is in oestrus {Macropus rufus} Sturt NP NSW

Owen Newman / Male Red kangaroo testing to see if female is in oestrus {Macropus rufus} Sturt NP NSW

IAN REDMOND / African elephant testing Kitum cave wall for minerals {Loxodonta africana} Mt Elgon