Why are insects attracted to light?
ASK! about Pets & Animals
Insects are attracted to light as they use light to navigate. Scientists “believe that insects that fly at night evolved over millions of years, before humans existed. Before humans existed, there were no artificial lights at night. The only light was the moon, and insects that fly directly towards the moon at night will travel in a straight line. This was therefore a useful behavior for them, helping them navigate in the dark. It is an *instinct*, meaning they don’t think about it, they just do it, because over the millions of years they’ve existed, insects that could navigate at night did better than those that couldn’t. Insects that fly towards an artificial light, however, will crash into it, and often hurt themselves. They can’t avoid it, because it’s an instinct. If we had another few million years to watch the process, eventually insects might stop doing it - but not yet; it’s only been a few hundred years.”
Taken from http://experts.about.com/q/
Entomology-Study-Bugs-665/Insects-Light.htm last accessed 20 Dec 2006
“Light and colour play an important part in the reactions of insects. The reaction to light is called phototropism. It is well known that many insects are attracted to light, the response to which is often greater than life itself. Light of short wavelengths, such as blue and violet, is usually more attractive to insects than other colours. Experiments have shown that all lights of the same colour do not attract insects proportionally. Much depends upon the intensity.
Although moths are attracted to artificial light, they keep away from sunlight. Butterflies on the contrary are attracted to sunlight but are repelled by artificial light. Butterflies are tuned to high intensities of light and moths to low intensities, so that the bright light attracts the butterflies and feeble light attracts the moths.
Insects generally orient themselves with their heads directly toward or directly away from the light source. Scientists observed that the moth is not attracted by the light but is oriented by it and, in constantly adjusting its head to the light, is drawn into it.”
Taken from http://www.science.edu.sg/ssc/detailed.jsp?
artid=1182&type=6&root=4&parent=4&cat=35, last accessed 20 Dec 2006
If your daughter is interested in reading up on more information on insects, here are some books that are available in our libraries.

My First book of Bugs and Spiders by Dee Phillips
Tunbridge Wells : Ticktock Entertainment, 2006
Call No.: JP 595.4 PHI
Click here for item availability.

Everyday insects by Bobbie Kalman & Rebecca Sjonger
New York, NY : Crabtree Pub. Co., 2006
Call No.: J 595.7 KAL
Click here for item availability.

What is an insect? By Lisa Trumbauer
Mankato, Minn. : Yellow Umbrella Books, c2006
Call No.: J 595.7 TRU
Click here for item availability.
Answered by Lim Shang Nee, Librarian, Children’s Services
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