This fear mechanism is critical to the survival of all animals, but no one can say for sure whether beasts other than humans know they're afraid.
这种恐惧机制对所有动物的生存都至关重要,但没有人能肯定人类以外的动物是否知道自己在恐惧。
2
Indeed, the outgoing affability of most dogs towards humans and other dogs is in sharp contrast to the mix offear and aggression with which wolves react to animals from other packs.