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Name: Amanda C. R.
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 2001


Question:
When roaches die, why are they usually upside down?


Replies:
Just a guess, but I suspect a lot of them die while standing on a vertical surface. Given the shape (rounded topside) and weight distribution (high center of gravity when standing since their legs weigh very little), from the aerodynamics, a falling roach would tend to land on its back. If you have the stomach to experiment, take a dead roach body and drop it multiple times from some height (e.g. a foot or two or three), from vertical (climbing wall), inverted (climbing ceiling), or right side up position. I think even from right side up a lot would land on their back.

A lot of dead roaches also seem to have their legs curled under them, which aside from having a high center of gravity, leads to a very narrow base, so the right side up position is unstable. A little breeze would knock it over and roll it on its back, a position where most of its weight is low to the ground.

Don Yee


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