Context
Human scent identification by police dogs

Olfactory signals provide a wealth of information essential to the survival of species in their ecological environment. The detection and identification of airborne olfactory molecules enables animals to adapt their behavior according to the type of signal they are indicating. The sense of olfaction thus plays a role in identifying edible and non-edible food sources, in detecting the presence of predators, and in social behaviors such as mate choice, mother-offspring relationships and group recognition. It's therefore easy to understand why the olfactory system has developed over the course of evolution, particularly in mammals, into a sophisticated and sometimes highly complex system enabling them to detect and identify thousands...