Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: Jennifer Sutton on 06/09/2008 15:48:13

Title: Why are insects attracted to light?
Post by: Jennifer Sutton on 06/09/2008 15:48:13

Jennifer Sutton  asked the Naked Scientists:

Hello Chis and Crew!

I'm a big, long-time fan of the show (http://www.thenakedscientists.com/HTML/podcasts/)! I have listened every week for years to the podcast (http://www.thenakedscientists.com/HTML/podcasts/) and enjoy it thoroughly despite the fact that I am in no way involved in the sciences.  In fact, I am studying for my master's in contemporary art/criticism in New York at the School of Visual arts.

This week I have a question: Why are bugs attracted to light? Do they possibly think it is the sun and use it as a sort of navigational device? Is it some sort of existential bug experience that they collectively seek? Are all bugs attracted, or just certain types?

Thanks in advance for your help and keep up the fantastic work!

Yours,

Jenni Sutton
Brooklyn, NY, USA

What do you think?

Title: Why are insects attracted to light?
Post by: blakestyger on 06/09/2008 19:55:50

When insects such as moths are attracted to light they are responding to a reflex called phototaxis.

Normally, they use distant light sources like the Moon for navigation and under this circumstance light reaches both eyes at the same intensity so the creature can fly in a straight line with both wings beating at the same rate.

The insect's perception is changed if the light source (a table lamp or headlight) is much closer as the light appears stronger in one eye than the other - which causes the wing on that side to beat faster. A spiral path towards the light is the result. [:o]