Scientists have identified a protein-like molecule (called a neuropeptide) that regulates sexual activity in insects.

The newly observed neuropeptide, called "natalisin," is "composed of short chains of amino acids in the brain of insects and arthropods," a Kansas State University press release reported.

This new finding could lead to more humane and environmentally friendly pest control methods. The molecule is only present in insects, so creating a substance that blocks it would not affect the sexuality of plants, animals, or humans.

Natalisn works with the bug's peptidergic system, which uses "peptides" to send messages throughout the body.

"Natalisin is unique to insects and arthropods and has evolved with them," Yoonseong Park, professor of entomology at Kansas State University, said. "It appears to be related to a neuropeptide called tachykinin that is in mammals and invertebrates. While tachykinin is involved with various biological processes, including the control of blood flow in mammals, natalisin is linked to reproductive function and mating behavior in insects and arthropods."

The researchers observed the changes in this sexual regulator through the egg, larva, pupa, and adult phases in the lives of multiple insects. The study looked at "fruit flies, red flour beetles and silk moths."

The team noticed natalism was expressed "in three to four pairs of neurons in the brain." They found that when there was an absence of the molecule, the insects were physically unable to reproduce and had less interest in sexual activity. 

"For example, we saw that knocking out the natalisin in the fruit fly makes them unable to mate," Park said. "The female is too busy grooming her body for the male to approach her. The male doesn't send a strong enough signal to the female to get her attention. We're not sure if that's because the male can't really smell her or because he is not developed enough to signal her."