Amazing adaptive behaviors of insects in your home: How cockroaches find mates in your kitchen, groom more than you do, and benefit from snubbing sugars

Insects that live in our homes (a.k.a., pests!) evolved incredible adaptations to deal with their enemies – you and I! We’ll discuss three of these adaptations:

1. The male German cockroach is exquisitely sensitive to a sex pheromone that the female produces when she is ready to mate. He navigates the complex landscape of the kitchen at night to find his mate. Our lab integrates chemistry, electrophysiology and behavioral studies to isolate and identify the chemical structure of the pheromone and thus decode the chemical language that cockroaches use to communicate with each other. Also, cockroaches recognize each other as members of the same species, as opposite genders, and as willing sexual partners by “tasting” unique chemicals on the cuticular surface. The German cockroach engages in courtship, nuptial gift giving, and ultimately copulation, all facilitated by a multi-component contact sex pheromone blend.
2. For pheromones to be detected by receptors inside the sensilla (hairs on the antenna) they have to penetrate tiny pores through the hard cuticle covering the antenna. Using a combination of field-emission scanning electron microscopy, gas chromatography and electrophysiology we found that cockroaches groom their antennae to remove a huge amount of natural wax that otherwise would accumulate and interfere with their sense of smell.
3. Finally, in their latest salvo in their arms race with us, cockroaches have rapidly evolved a new behavior that protects them from our toxicant-laden baits. They reject sweet-tasting glucose which represents a signal for a bait that will kill them. We’ll discuss the underlying neural mechanisms of this glucose aversion behavior as an example of the plasticity of the sensory system to adapt to rapid environmental change.