In past EleFACTs, we have shared extensively about the ability of elephants to use their five senses in their day-to-day lives, sometimes in remarkable ways. From their dichromatic vision, to their impressive sense of hearing, to their use of touch to communicate or use tools, we have covered many aspects of their anatomy and physiology. Today we want to re-examine the vomeronasal organ, or the Jacobson’s organ, which helps to put these senses together to aid in chemical and olfactory communication.
The Jacobson’s organ exists as a patch of sensory cells in the nasal chamber and detects heavy moisture-borne odors. Elephants will “moisturize” the tip of their trunk with secretions from the nasal cavity and mix it with other fluids from the body, like urine. The tip of the trunk is then placed into their mouth to make contact with the vomeronasal duct in the upper part of the mouth. Here, nerve endings allow for the sensing of the chemicals, or pheromones, contained in the solution. For example, male elephants will use the urine from females to collect reproduction information that exists in the chemical makeup of the fluid. It is fascinating to think that so much information can be collected that ultimately leads to the furthering of the species.
This organ isn’t just for reproduction. Young elephants can use the Jacobson’s organ to instantly distinguish between their mothers and other female members of the herd by putting their trunks into each other’s mouths.
In other species, this organ is exposed in a way you may recognize; in what is called the flehmen response, an animal (think of a horse) may open its mouth and curl back their upper lip while inhaling, capturing the airborne chemicals. Other animals that make use of this organ are snakes, who use it to sense prey by sticking their tongues out to gather scents and touching it to the opening of the organ when the tongue is retracted, and painted turtles, which use it to smell underwater.
Photo of Bambi