Why are moths active at night?

[padanarm]

Why are moths active at night? Most insects, flies and butterflies come out during the day. Presumably this is because they use the sun's warmth.

It must be colder at night so why can moths survive at night without the sun?

[BeatySwalls]

its because they are nocturnal

[China-Doll]

Pretty much what Beaty says. Moths are nocturnal and use the moonlight as a navigator.

[BeatySwalls]

Moths fly by night, but can have very good night vision. Of course, they need some light to see by, particularly moonlight and starlight.

Moths and other night-flying insects fly in a straight line by reference to the relative direction of the moon. Because the moon is so far away, the direction to the moont is fixed at any one time, no matter how far the moth flies (and the moths have evolved to take the moon's direction of travel across the sky into account).

However, when they see a bright light close by, and confuse it with the moon,their navigation instinct gets out of whack. In this case, instead of being constant, the angle to the light varies as the insect flies past. So instead of travelling in a straight line, they fly in a curve around the object, when trying to keep the source of light at a constant angle to their flight path. (That is why the spiral inwards towards the source of light).

Incidentally, insects (and birds) that fly by day navigate by the sun; but there is less chance of another bright source of light confusing them.

[padanarm]

Sorry, you've missed the point of the question.

I thought flies and butterflies were active during the day because they used the sun for heat. At night there is no sun (duh!) so where do moths get their heat from?

Is moth biology different from day-flying butterflies? Is there an ecological advantage in being active at night?

[BeatySwalls]

maybe you should try this web site I made follow the link and ask the question on there.
http://beatyswalls.uuuq.com/beatyswalls.html

[burnhal]

It is a popular myth that all moths are night flyers. In fact you will find there are probably well over a hundred day flying species. Night flyers have evolved because their food plants tend to be more attractive at night- eg honeysuckle gives off a powerful scent at night, making it easier to find.

[burnhal]

Oh- and night flying moths vibrate their wings- this heats up the flight muscles as, you quite rightly say, they dont have the sun to do that for them

[padanarm]

Thanks burnhal, didn't know about moths vibrating their wings.

[wildwood]

Most moths have evolved to become nocturnal because it is to their advantage. Most birds are asleep when they are active, although bats are pretty good at zooming in on them.
Their gradual change to a nocturnal lifestyle has happened in symbiosis with the flowers that open (or stay open) at night so moths can feed on their nectar and transfer pollen.

Moths are able to venture out in cold weather better than other insect because they have scales that are in the shape of hairs, insulating their bodies from direct contact with the air. They still prefer and are always more active in warmer nights though.