As a side note (let's start with the side note), I definitely believe that human psychology is very important because we never know the state of emotion of the others. It is important to behave nicely together. And I guess that’s it.
With respect to this sentence:
we can make our behavior understood verbally
Don’t you think animals can also communicate with each other through their own language? The fact that they don’t speak ‘human’ is different from not being able to verbally communicate, isn’t it? Why should animals adapt to humans and not the opposite? (I know, I try to square the circle ;) ).