So now that it's beginning to feel like winter, I've been thinking, what are some things that people like more about winter than summer besides snow, winter sports, and Christmas. No flies! They are summer's most annoying pesks. Many idioms, similes, and metaphors use flies to describe unwelcomed creatures.
If you were on vacation in the summer, and flies were a daily nuisance, why would they all suddenly disappearing when the evening wind picked up? What is it, and why? Where do they go?
To answer this, there is is a maximum wind speed above which they will not fly, but the reason also depends on temperature, humidity, and the sex and age of the fly, as well as species. Lucilia Cuprina is the major sheep-infesting fly. Its wind speed threshold is about 20 mph. It is also grounded if temperatures are hotter than 104 degress Farenheit and below about 54 degrees Farenheit. When they are stopped from flying because of these conditions, they crawl into small protected spaces until conditions improve.
Before I found this, I rarely ever noticed the behaviour of flies. Who knew they have a wind limit?
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