The neurology of firefliesLast year and this one, I've have a chance to sit out in the summer evenings in our sunroom and watch the day turn to dusk, then to dark. And then out come the fireflies this time of year.
What I've noticed is an interesting phenomenon, interesting to me anyway. We know that the male firefly is flashing its light to attract the female, but there is something in particular I've noticed about this. In the vast majority of cases, the firefly is on an upward flight while it flashes, and many times very close to a straight vertical flight. When you can see the firefly after the light goes out, there is an immediate downturn in the flight trajectory when the light goes off.
I suppose we might hypothesize that, well of course, the firefly "wants" to increase the likelihood of some female seeing him, and how better to do that than to fly upward? Or maybe flying upward is a sign of "male robustness" and therefore of a fitter male. Seems dubious to me, as if we're assigning a lot of cognitive activity to a firefly, or invoking Darwinism to explain this.
What I wonder about is whether there might be some more simple neural connection here. For example, does the neural activation of the lighting mechanism (release of the chemical) cause a spillover of neural activity that increases wing flapping and therefore upward flight? Or perhaps increasing wing activity is a necessary precursor to this. I know from experience of catching and putting fireflies in a bottle as a kid that they can light their lights without flying, but maybe when flying and lighting happen at the same time there is some neural synchrony...
I tried googling this, but not surprisingly this seems to be quite unmentioned or unnoticed.
This also reminds me of a former patient of mine who had ALS, and a very colorful man he was. One visit he told me he was sitting in his backyard one evening, and wondered if he should grab fireflies and eat them to try to counteract the disease. We laughed about it, but then a few days later he mailed me a copy of a newspaper report indicating that scientists were using fireflies in order to try to understand some things about the human nervous system.