Domesticated animals are bred that way over generations. All domestic dogs relate back to the wolf. Odds are that Beta Males who were kicked out of packs gathered around human settlements and the humans got the easier to domesticate dogs right off the bat (well easier than an Alpha male wolf) but through years and years of breeding and selecting which traits were good, which traits were bad etc we have the nice doggies we have today. It took lots of time to do that.
Wild animals are WILD...it might seem a bit repetitive but it's true. These animals like the lions and the ape may have had to be re-trained to be "wild" but they were never "domesticated".
For example Koko, the ever so famous sign language talking gorilla....seemingly docile and friendly would every so often rip sinks out of the walls. Which is disconcerting...she did blame that on one of her kittens but just imagine that, if Koko got a little irritated at someone she could quite easily dismember them with only her hands.
In an interesting reversal of this "domesticated pigs" the pink Babe lookalikes can revert to being feral in a matter of hours. And VC can, I am certain, explain how destructive those bastards are.....deadly sob's too!
Bookmarks