Why are dead bugs, cockroaches for example, usually found on their backs?

Answer 1

The bugs you see dead around the house are found on their backs because they have been poisoned. The poison causes their muscles to spasm, and that in turn causes them to flip over. Normally a bug that has flipped over can right itself, but the posion prevents muscle co-ordination and stops them from righting themselves. So when they die they are found on their backs.

In contrast bugs found dead in the garden are just as often found dead in standing positions or lying on their sides.

Answer 2

First, few cockroaches die on their backs in the wild. Natural death of cockroaches probably occurs in the stomach of a bird, bat or other small animal.
Second, Cockroaches are not used to living on a polished marble or vinyl floor. They are more used to a ruguous living plane including leaves and sticks and other vegetable debris. Thus when a cockroach finds itself on its back (by some mistake in its orienteering) it may have trouble righting itself if there is not debris around to grab hold of with its legs. (Try it, put a cockroach on its back on a polished floor with and without some crinkled paper.)
Third, often we come across dead cockroaches in buildings that have died of insecticide. Most of these insecticides are organophosphate nerve poisons. The nerve poison often inhibits cholinesterase, an enzyme that breaks down acetyl choline (ACh), a neurotransmitter. With extra ACh in the nervous system, the cockroach has muscular spasms which often result in the cockroach flipping on its back. Without muscular coordination the cockroach cannot right itself and eventually dies in its upside down-position.

Answer 3

They don't turn over onto their backs as an intended act.

It might be that because the legs of most insects are lighter
than the body, and so once they are dead they would be more likely to be tipped over by any external force and gravity.

Answer 4

Cecil Adams, the columnist who writes "The Straight Dope," gives a reply about why roaches die on their backs at: http://www.straightdope.com/classics/a1_024.html

Jurgen Ziesmann gives a different answer at http://www.madsci.org/posts/archives/oct99/941200500.Zo.r.html
Since Jurgen Ziesmann's field is zoology, I'd choose it over the first one.

Answer 5

Usually when these bugs die and are found in this possition is because for one reason or another they fell in this possition and couldn't turn back. They usually die of hunder or dehidration.

Answer 6

girls do not play with bugs....stop stealing our toys and games