Is there any logical explanation for why a lot of insects are attracted to light?
You'd think there would have to be some benefit for them, but what is it? It sure doesn't seem to do them too much good.
I've heard of a theory that they are trying to use the light as a guide to fly in a straight line or something, but I don't know if that really makes a lot of sense. Before there were people to turn on porch lights, the brightest light at night would have been the moon, but why would a moth want to fly towards it?
Just wondering
Jim S.

Perhaps because they know that their preditors that eat them are blinded by bright lights for those preditors are nocturnal and feed only at night which means their eyes are adapted for very dark environments not bright ones. :shrug:

A popular theory. Moths use the moon at night (as sailors use the North Star) to orient themselves in flight, but brighter local lights (porch lights, streetlights, etc) overwhelm moths’ attention and cause them to a circle and/or spiral into those lights.

Intriguing newer hypothesis, supplementing the navigational one: moths tend to fly to relative darkness, and in their visual field there is a halo of relative darkness around a bright light source - the edge of the bright is the darkest (perceived) area in their field of vision (human visual processing also produces this illusion).

so they fly to that, and curves them into the light. The light itself, when they get close, simply dazzles them, in this view - overloads their circuitry, producing confusion.

Support for that hypothesis is found in the erratic behavior of many moths approaching a light - often they don't spiral in smoothly, as the navigational hypothesis seems to predict.