It is a mystery that I have never fully understood. What's the big attraction for moths and other flying night beasties?

Someone once told me it was because they navigate by the moon. I find that a very tall explanation!

Any ideas?

No idea but they don't half stink our living room out when they fly in to the uplighter :rolleyes:

Aren't moths nocturnal? Doesn't that make it even more odd that they are attracted to light?

Wikipedia suggests it is unknown (http://en.wikipedia.org/wiki/Moth#Attraction_to_light), although at least gives a vaguely plausible reason about why it would make them circle the light. The Mach band theory the article links to is interesting too, although it also sounds a little like clutching at straws :)

I always thought it was because they navigate by the moon using it as a reference point to adjust their flight. Stick a brighter artificial moon in the way and they try and navigate by that instead but as they try and adjust their flight in rlation to the lamp they end up circling it rather than flying in a straight line?

Yeah, that was the plausible reason in the wikipedia article. Sounds possible, but also sounds vaguely like some of my "made up in the pub after a couple of pints" reasoning :) May be true, I guess it's difficult to prove. My other thought was: where do moths need to navigate to anyway?? :) I know, I know, it's just their frame of reference, but wouldn't they want to fly off in a random direction after a bit to get some food or something?

I'd always been told the thing about the Moon was correct; would be interested if anyone can confirm for definate.

You will find 99% of entymologists/biologists will confirm that which has been taught for a long time.
Like a great deal of our learning, it is theory, but it is a wrong emphasis of Wikipedia say that the answer "is not known".

Here is a clear summary that I found quickly. You will find similar from more technical sources if you wish.

Moths aren't so much attracted to artificial lights as they are disoriented by then. A nearby light source is like a powerful drug to a moth. That makes sense because -- aside from the occasional forest fire -- earthly light sources have been in existence for only a very short time in contrast to the history of the moth.

Like many flying insects, moths are able to find their way partly by using light as a compass. When the source of light is the sun or moon, that light source is very distant -- and the incoming light rays striking the insect arrive just about parallel to each other. So moths -- and many other flying insects -- have evolved to expect to receive light at a fixed part of the eye. As long as the moth flies more or less in a straight line, this visual pattern remains unchanged.

Now consider what happens when the light source is a nearby streetlight. Then the angle at which the light strikes the moth's eye quickly changes while the moth holds to a straight-line course. The moth tries to maintain a constant angle to the source -- and as it does so, it spirals in toward the light. So the moth seems "attracted" to the light -- so much so that it may end up colliding with it!

http://www.earthsky.com/shows/earthcare/showsmore.php?t=20021202&s=s&h=Animals

Flys do it too! well the big fat bluebottles do anyway, there was one in our kitchen the other week. It just kept flying into the light strip over and over upto the point it got tierd fell to the floor and was eaten by our cat :gag:

Okay, try explaining THIS away then, why is it when you have flies in ya house, they always congregate around the light bulb, even when it is switched off ????

I could understand if they was on at night, but, during the day, when they are off, hmmmm, weird.

Why can't flies ever find their way out through an open window ?

wonder if its somthing to do with the gas inside the bulbs?

Originally posted by nick2
Why can't flies ever find their way out through an open window ?
Maybe its a fly 'extreme sport' :hihi:

Originally posted by nick2
Why can't flies ever find their way out through an open window ?

I know this! I know this!

The fly wants to go out the window but is held back because there is a difference in air pressure. It's like an invisible brick wall.