h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

question: why do moths come out at night and then be obsessed with light?
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its protective: during day they get eaten by birds, night less preditors, but I know what yo mean, the light at night I can't readily guess, but I've been drinking 25 yeqar single malt, so I'm not guy to ask

I don't know the precise details, but it has to do with moths navigating by the moon. Moths not being very bright they can't tell the difference between moon and lightbulb.

Noggin

It's not really down to intelligence - moths evolved when the brightest thing at night was the moon. They can't adapt away from this behaviour becouse human light distribution is directionaly meaningless. There are, however, plenty of expanses of the planet without humans, so it pays to keep this method of navigation. And, let's face it, if it were that much of a problem, we wouldn't have any moths left.

They're certainly thriving around here!

They are also drawn to light coloured flowers, so maybe they think it's just a really great flower.

Moths are night-time animals. They live and night and find their way around mostly by scent. Moths have the most sensitive sense of smell of any animal. A male moth can smell a female of the same species if as little as one molecule of her scent reaches his smellers, which are antenna rather than being located inside his nose. I'm sure there is a more technical name than smellers.

Moths use the moon for navigation. A moth decides which way he wants to go, looks at where the moon is, then flies with the moon at a constant position in his vision. Because the moon is very far away, this means he flies in a straight line. If he sees a light and thinks it is the moon, he will keep it a particular postion in his vision, but because the light is close, these means he will spiral towards it in a logarithmic (equiangular) spiral until he strikes the light. Being not very intelligent, he then proceeds to do exactly the same thing again.

and get squished by a rolled up newspaper if I'm on my own. I've got vague recollections of doing an experiment for an OU course involving a light trap & moths, I think it used an ultra-violet lamp, are they more attracted to ultra-violet?

"Moths not being very bright they can't tell the difference between moon and lightbulb."

If they were very bright, they'd keep flying into each other...

Sorry, I'm not being helpful, am I?

B

Thanks for that answer Gnomon, I'll be paying more attention to moths if they come indoors again.

Cheers everyone that my mind rest for a while any many other not on line people two.
Thanks gnomon for your help in this matter.it's great to know there's a place that will have people intressed enough to indulge my Questioning.
(Beer all round and some cake too.)
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