Insects Groom their Antennae to Sharpen Senses

Cats are thought to be the ultimate narcissists, as they are continuously grooming themselves to remain clean. But then insects seems be following their traits as they spend a lot of time in grooming themselves.

A latest study conducted by researchers at the University of North Carolina State University shows that insects spend an ample amount of time in cleaning their antennae in order to sustain sharp olfactory senses. This helps in hunting down their prey, sensing danger and locating a suitable mate.

Insects clean the environmental pollutants and chemicals that are produced by the insects themselves.

In order to understand why some insecticides work more effectively than others, entomologist Coby Schal along with postdoctoral researchers Katalin Boroczky and Ayako Wada-Katsumata explored the function of insects grooming themselves.

By conducting an experiment, they tried to figure out what material gets accumulated on their antennae, the source of the material and how different a groomed antenna is from an ungroomed one.

For this study, the clean antenna of an American cockroach was compared to the antenna that was experimentally prevented from being cleaned. They noticed that grooming cleans the microscopic pores present on the antennae that serve as a channel for chemicals traveling to the sensory receptors for olfaction. By using the forelegs, they place the antennae in the mouth in order to clean every segment of it.

On the other hand, the ungroomed antennae had already accumulated both non-volatile and volatile chemicals. To their surprise, they found a great amount of cuticular hydrocarbons on the antennae. These waxy substances are important for insect communication and are also used as a waterproofing compound.

"It is intuitive that insects remove foreign substances from their antennae, but it's not necessarily intuitive that they groom to remove their 'own' substances," Schal said in a press statement.

Apart from this, they also estimated how the cockroaches picked the scent of a known sex pheromone compound as well as other scents. They tested this for both groomed and ungroomed antennae and saw that the groomed antennae responded quickly to the signals.

"The evidence is strong: Grooming is necessary to keep these foreign and native substances at a particular level," Schal continues to say. "Leaving antennae dirty essentially blinds insects to their environment."

The findings were published in the journal Proceedings of the National Academy of Sciences.