|MadSci Network: General Biology|
Well what a question to start the new year with :-) This one has had me cogitating for a few days so that I can give you my best shot at an answer and I think the first point is that they don't!
While I am sure that some dead cockroaches are upside down when they are found; I am not so certain that this is in any way related to the process of their death. My theory is that cockroaches like most insects when dying tend to do so on their feet and that they are turned over subsequently by other inquisitive or hungry animals. The dorsal (or upper side) of a live cockroach is covered in hard cased wings which gives the roach protection from predators. Once dead other animals would want to turn the roach over to get at the edible part underneath, where its legs are usually holding it to the ground.
However, I must admit I am not an expert on cockroaches, but surfing the net I have found a man who is: David George Gordon. So you might like to read his book:
A Comprehensive Guide to the Most Despised (and Least Understood) Creature on Earth
or check out his The Compleat Cockroach Travelling Road Show
He can also be contacted by email at firstname.lastname@example.org
(David George Gordon & Associates, Inc.)
I hope that this is of some help.
Happy New Year,Hes
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