Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: Variola on 13/08/2009 16:22:42

Title: Why do flies buzz round and round my lightshade???
Post by: Variola on 13/08/2009 16:22:42

Hello forum peoples!

Why do houseflies buzz round and round in circles underneath the light shade on the ceiling? I mean, what is the point? They do buzz round other areas of the house, but then they still come back to buzzing round and round the same spot.

Any thoughts??


The Pox

Title: Why do flies buzz round and round my lightshade???
Post by: RD on 13/08/2009 22:23:57

Straight dope Cecil debunks the "moths mistake lamp for moon" hypothesis ...
 http://www.straightdope.com/columns/read/1071/why-are-moths-attracted-to-bright-lights


This 1974 hypothesis sounds more promising...

Quote

The corn earworm moth, Heliothis zea (Boddie), emits a 10-μm infrared signal which is chopped by the wings. The oscilloscope recordings demonstrate that the signal has an azimuth and a glide path vector. A burning candle randomly mimics the vectored infrared output of the corn earworm and other moths. The output of the moth is related to the peculiar affinity of a moth for a candle flame. It is postulated that the vectored infrared signal may serve as a homing device between the sexes. It is believed that a candle flame is a confusing mimic to the moth signal and that the infrared from the flame triggers the “candle flame” behavior of the moth. There are picket-fence sensors (coeloconica) on the antennae which may be infrared detectors for the signal.

http://www.ingentaconnect.com/content/esa/aesa/1974/00000067/00000003/art00008?crawler=true

So to a moth a flickering flame looks like a hot date, (in reality rather too hot).

Moths and flies may initially drawn to the infra red emissions from the light and may leave their scent on the lamp shade,
 so other insects are still drawn to light shade even when the light is off because of the scent deposited there when the lamp was on.

Title: Why do flies buzz round and round my lightshade???
Post by: Don_1 on 14/08/2009 07:58:53

I read a suggestion that the ceiling, to a fly, is like a featureless sky, so it will head for the only feature in that sky, the lamps hanging down from it. The suggestion seemed to be that the fly uses the lamps as a point of reference.

Personally, I am sceptical about this. If it were the case, then what would a fly do when outside on a clear, cloudless day? Head for the sun?

Title: Why do flies buzz round and round my lightshade???
Post by: RD on 14/08/2009 10:28:22

Quote from: Don_1 on 14/08/2009 07:58:53

... the ceiling, to a fly, is like a featureless sky

What if you've got 17th century beams or 1980's artex on your ceiling  [:)].

Title: Why do flies buzz round and round my lightshade???
Post by: Variola on 14/08/2009 10:57:13

Thanks RD!! And to Don too  [:)]

Im still baffled as to why they just buzz round in a circle under it, sometimes they do rest on it but then they continue to buzz round under it, often with another fly doing the same beneath it. It reminds of of how they stack planes up ready to land at an airport.