Why do insects fly into a light source and if it's biological, why haven't they evolved away the behavior?

Answer 1

Its generally believed that many insects navigate using the moon
and that flying into the light is caused by them mistaking it for moonlight. As regard to the second part of your question evolution does not necessarily work efficiently. I am sure that there would be some varieties of some insects that have wiped themselves out by flying into lights, perhaps even some species. Insect reproduction can be so prolific that if 99% of them cream themselves on your high beams the 1% left may be enough to continue the species. Also collecting around streetlights for example might be advantageous, an insect might collect a mate

Answer 2

Because electric lights have only been around for roughly a century.

The facination with lights stems from the way they navigate using the moon. A simple mutation probably won't be enough to alter their behavior, a sequence would be needed. As long as they can successfully navagate with the moon the losses from human light polution won't be enough to select against the behavior.

Then again, maybe we only see the individuals or species which haven't lost the behavior yet.

Answer 3

Flying towards light is actually an evolutionary advantage. Insects often fly towards the moon or towards the sun in order to navigate. This is why they often fly into man-made lights.....they think they are flying towards the moon or the sun.

Also, there has not been significant time to evolve to recognize man-made lights as being different from moon or sunlight.

Answer 4

There is no evolutionary disadvantage to flying toward a light. The bugs that get caught by a bug zapper are insignificant to the fitness of the species.

Answer 5

How long have insects been around?
How long have lights been around?
Thank you !

Evolution and time are like bread and butter, one doesnt work so good without the other.

Answer 6

It's temptation I think like humans can't resist temptation...