[GlickWick]

Cockroaches are pretty impressive and live a long time, at least as far as insects go. Fruit flies measure life in the order of hours, but roaches can live for a year or more. I suspect you need a more complex nervous system to assess and survive in an environment as a prey animal for long periods of time, whereas fruit flies can likely just brute force it.

[Chaosvex]

Fruit flies can live for well over a month. The hours belief is a myth.