# Winter housefly origin

**URL:** <https://boards.straightdope.com/t/winter-housefly-origin/956519>\
**Category:** Factual Questions\
**Created:** [December 23, 2021, 3:28am UTC](https://boards.straightdope.com/t/winter-housefly-origin/956519 "2021-12-23T03:28:07Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\
**Post date:** [December 23, 2021, 3:28am UTC](https://boards.straightdope.com/t/winter-housefly-origin/956519/1 "2021-12-23T03:28:07Z")

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It’s deep into the cold season here in Chicago, though it’s been more mild than usual. Today, I heard a housefly buzzing around and caught a few glimpses, looked like just a regular fly we see around here during warmer months. Where did it come from? The house is pretty well sealed up, storm windows are down and plastic over the big drafty ones in the kitchen and I don’t get many in the house during the summer, anyway. Don’t the juveniles/maggots need to feed before becoming flying adults? I regrettably don’t have raw meat or dog crap or other gross things laying around that would nourish fly larva and am wondering where a single fly how show up in the house this time of year.

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**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\
**Post date:** [December 23, 2021, 4:11am UTC](https://boards.straightdope.com/t/winter-housefly-origin/956519/2 "2021-12-23T04:11:09Z")

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Insects can go into a dormant state called diapause. Flies do this as adults.

> **[Diapause](https://en.wikipedia.org/wiki/Diapause)**
>
> In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions. It is a physiological state with very specific initiating and inhibiting conditions. The mechanism is a means of surviving predictable, unfavorable environmental conditions, such as temperature extremes, drought, or reduced food availability. Diapause is observed in all the life stages of arthropods, especially insects. Embryonic diapause, a somewhat sim Activ...

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**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\
**Post date:** [December 31, 2021, 1:54am UTC](https://boards.straightdope.com/t/winter-housefly-origin/956519/3 "2021-12-31T01:54:58Z")

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I am sorry for the long delay.