Insects are constantly under attack by humans because, well, they eat *our* food, they infest *our* houses, they give us disease, and–for the sake of complete honesty–that buzzing in our ears is just plain annoying.
But when an insect comes home after a long day at work doing whatever insects do–I don’t know, I assume most of them have desk jobs where they go over paperwork to plan next year’s locust swarm or something–they quickly find their houses dowsed in pesticides, with the only suitable accommodation left being that creepy Roach Motel down the hallway.
I think it’s fair to assume this would stress anyone out.
I know what you’re thinking, though–insects have brains smaller than a grain of rice! They’re icky, they’re sticky, they’re dirty. They can’t possibly have feelings.
And that’s where you’d be right, at least from a psychological point of view. But neurologically, insects are capable of registering stress, and their bodies respond accordingly. For example, locusts suffering from pesticide-induced anxiety have increased fight-or-flight responses, which, in their case, literally means they can fly better (flying to the organic farm a few miles away, most likely).
How does this work? One of the main insect stress hormones is called adipokinetic hormone, or “AKH.” This hormone helps release energy stored in an insect’s fat body, in addition to other physiological stress responses mediated through G coupled-protein receptors, similar to the way in which glucagon works in the human body. With additional nutrients available in the insect’s hemolymph, there is more energy available to power wing muscles, increase the immune response, and really anything else that’s necessary to help the anxious little arthropod through this tough time.
The next time you swat at a wasp, just remember the anxiety you’re causing for the little guy. With these hormones racing through that tiny insect body, he’ll have to stress-eat wood pulp, die his setae blue, and maybe even join an alternative punk-rock band just to cope with it all.
If you’re interested in learning more about the similarities between insect and human stress physiology, check out this review (.pdf) by Andrea Bednárová, Dalibor Kodrík, and Natraj Krishnan.