Why Are Moths Attracted To Lights? -- The Real Answer

MyName nospam at noaddress.com
Wed Dec 29 23:01:42 EST 1999

I've been meaning to post this for about 10 years now, but for some reason I
always forget to share it on the newsgroups. I've told quite a few people but
have never posted this publicly, til now.

I'd like to set the record straight. Moths do NOT travel towards lights for some
navigational purposes. Moths do NOT travel towards lights for some reproductive
or food source seeking purposes.  Tear out all those useless entries in your
science books. And for heaven's sake PLEASE stop teaching these WRONG answers to
any students or children you might know.

Why do they travel towards lights? Simple (and only answer) -- They want to
sleep.  (Now _that_ is an answer I can relate to. :-)

I used to attract moths to my screened window using a U.V. lamp so that I might
photograph them.  I would wait until they had settled down to a resting state,
then very carefully opened the screen, picked them up, brought them inside,
photographed them, then released them outdoors when done.  If I jostled them too
much they immediately started to shiver to raise their muscle temperatures to
ready them for flight. I would stop what I was doing, and wait for them to go
back into a sleep-state by holding them near a bright light then continue on
with my photography.

Now you ask, why would they want to sleep? Simple answer: When they are in a
sleep cycle they are the most safe from predators.  I've noticed that this need
to remain camouflaged and still is even more powerful than their need to
reproduce.  Many (nearly all) species will even forgo finding appropriate food
plants to lay their eggs on. Instead they will lay their eggs right on my window
screen if I leave the U.V. light on for a period of days.  Content to stay
there, totally asleep, their eventual egg-laying cycle taking over while

This finding of mine has some overwhelming consequences.  The main one: Light
pollution may be doing more harm than we ever thought possible. How many
species' (not only moths) mating and egg-laying cycles are being disrupted by
light pollution? Could this account for some of the decline in amphibians and
other insectivore species world-wide? You can take further possible consequences
from there. In order to save our ecosystems it might one day be a mandate to
turn off your outdoor lights at night.

In any case, I have to lay to rest some of the outmoded and utterly ridiculous
myths of why moths go to lights. Hasn't anybody ever stopped to realise that a
moth travelling in a straight line by navigation using moon-light or star-light
(the usual old theory) would serve ZERO purpose to a moth?  Why would travelling
in a straight line afford them more food sources or the chance to find a mate?
That's just silly. There are no straight lines in nature. Their mates are not
lined up like bottles on a fence rail nor are their food supplies.

(As with all my discoveries in life, I post this anonymously. The same as I did
on a local BBS back in 1980 with my answer to the "chicken vs. egg" koan.  Oh,
you've not heard that answer? Simple: The only place that mutation can take
place is in the egg.  Therefore, something "not quite a chicken" laid an egg.
That egg, by chance, now had the genetic code to be a "real chicken".  The "REAL
chicken" egg came first.)

Too bad I don't have some academic-shingle sig to tack onto this post to make my
finding more acceptable to your linear minds. But I'm just a simple man, a
naturalist, watching nature my whole life and seeing how she behaves.  This is
just one more correct page in the book of "The Nature of Nature" that I have
come to know so well.

We now return you back to your learned scientists and all the mistakes they have
made and taught you in school, lo these many years ...

"What does education often do? It makes a straight-cut ditch of a free,
meandering brook."  --  Henry David Thoreau

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