Science Insider presents the 4-minute film “Why Cockroaches Are So Hard to Kill”.
A super immune system, a huge number of olfactory an taster receptors make them able to eat anything. The American cockroach has a very large genome.
If it is decapitated, the body can survive a week.
It also molts almost its entire body several times in growing into adulthood.
Wikipedia embed: head of American cockroach