In Cole Porter’s 1928 hit “Let’s Do It, Let’s Fall in Love” the different refrains reference insects, birds, marine life, humans and more, declaring more than sex was fun, sex has a purpose, and indeed love can be in the air. Porter gave us a fun and fairly comprehensive rundown of the pervasive, seductive, and powerful influence pheromonal communication plays in animal behavior and the reproductive process. Most of the animal kingdom communicates and coordinates their activities for survival through chemical signals that define physiology and behavior. Proteins, peptides and other chemicals are used as pheromones, cues linked to their purpose and function. These airborne signals that can travel great distances, sending an alarm, marking territory, attracting a mate, signaling reproductive readiness or helping them detect a predator or tack prey. Animals have a variety of ways for releasing and receiving chemical codes.
• Did you think that horse was laughing? Ever see an animal holding its head up, neck stretched, curling its lips back so far you can see the teeth and gums? You might have seen your dog or cat do it, but even water buffalo do it. What their really doing is getting a better read on the chemical information by driving molecules to their vomeronasal organ. Snakes, too, taste the air with their forked tongues to bring pheromone molecules to the receptors in the roof of their mouths. This behavior is often referred to as the Flehmen response.
• Hamsters release a protein in their vaginal sections called aphrodisin that serves as a sexual attractant.
• There are non-volatile pheromonal signals that are long lasting and are used for social recognition. Deer have flanked and leg glands that release chemicals, serve as identifiers, and allow their offspring to find them.
• Sheep utilize pheromonal signals in the springtime. Rams send these pheromonal messages to synchronize induction and estrus in the ewe. This is due to the ram’s capacity to produce pheromones in his wool, wax and urine (wax is a pheromonal substance produced around the eyes and flank).
• The vomeronasal duct (VND) is an auxiliary olfactory sense organ found in many animals, and it remains very important to both normal social activities and reproductive behavior. Turtles and other species are able to smell underwater because of this organ.
• The same compound, the aromatic aldehyde bourgeonal, that attracts a bee or hummingbird to a flower, is the same that attracts the sperms to swim to the egg in humans.
• Though most of these smells are synthesized now, humans once used animalistic scents in early perfumes, such as: secretions from the African civet cat’s anal gland (an odor the cats used to mark territory), the contents of a male musk deer’s scent pod, gland secretions from beavers, and the intestines of sperm whales.
Sometimes we fail to grasp the complex interconnected thing of beauty in which we are embedded. Chemical communication has always been the blueprint for the continuation of a species. However, for humans, how well it works now depends on the receiver’s ability to extract information within the original function of the cue.