This explains why all animals on the planet can get stoned, it is because all life originated from the see and we have all inherited the same nervous system from early sea life. It is an accident that the chemical THC found in cannabis affects the nervous system in the way it does. “The reason that cannabis gets you stoned is due to an accident of evolution” This is a clip from BBC Horizon: Cannabis The Evil Weed? It is on you tube if you wish to watch it.