[wayner]

There was that incident in the news where a chef cut the head off a cobra to cook it, and then sometime later the head bit him

Snakes have extremely slow metabolisms, so therefore they don't need fresh blood pumping to live a long time.

Its one of the reasons why Snakeskin boots etc are not legal to import into Canada.

The suppliers just cut their heads off and throw them in a pile, to die a long slow death.
The humanitarians (or maybe snakatarians) don't like that idea since it isn't seen as humane to allow an animal to live after cutting off its body.