Flehmen response: an American Bison bull is using his sense of smell to verify whether a female is ready for mating or not

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American Bison (Bison bison) A bison bull is using his sense of smell to verify whether a female is ready for mating or not: certain pheromones in her urine will give her away. The reaction of the male is called flehmen, or fleming: he is rolling up his upper lip, so that the air goes through a special nasal organ (the vomeronasal organ) that will detect the pheromones more accurately. Yellowstone, Montana, USA

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Size: 4928px × 3280px
Location: Yellowstone, Montana
Photo credit: © Arturo de Frias / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 2013, america, american, americano, artiodactyla, bison, bisonte, bovidae, fauna, flehmen, flemen, fleming, mammal, mating, montana, nature, north, oestrus, reproduction, smell, usa, vomeronasal, web, wildlife, yellowstone