Metatarsal odor

Black-tailed deer possess three glands which along with urine play a role in social chemical communication among their conspecifics. The tarsal scents acts in individual recognition, the metatarsal odor functions as an alarm pheromone and the substances from the forehead are employed for marking (193). 

The response to metatarsal odor consists of increased alertness. Only females show a response and they do so to both male and female metatarsal scent (254), but Odocoileus virginicus, the white tailed deer, does not exhibit this alarm behavior system to the same degree (299). It has also been observed that two subspecies of blacktailed deer, O. he-mionus columbianus and O.h. hemionus, can distinguish each other in this manner. Such discrimination may be important in sexual isolation of the species (254). 

An animal can control release of odor molecules from body surfaces, especially skin gland areas, up to a point. But in moist air, volatiles from secretions on skin or hair will evaporate more easily. If only intermittent odor emission is desirable, humidity would interfere with the animal s odor release. Glands that produce such intermittent signals, such as alarm odors, appear to be more developed in species or subspecies in drier climates. An example is the metatarsal gland in... 

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