...Since a baboon does not know or worry about what another baboon knows, it has no urge to share its knowledge. Dr. Zuberbühler stresses an intention to communicate as the missing factor. Children from the youngest ages have a great desire to share information with others, even though they gain no immediate benefit in doing so. Not so with other primates.
“In principle, a chimp could produce all the sounds a human produces, but they don’t do so because there has been no evolutionary pressure in this direction,” Dr. Zuberbühler said. “There is nothing to talk about for a chimp because he has no interest in talking about it.” At some point in human evolution, on the other hand, people developed the desire to share thoughts, Dr. Zuberbühler notes. Luckily for them, all the underlying systems of perceiving and producing sounds were already in place as part of the primate heritage, and natural selection had only to find a way of connecting these systems with thought.
Yet it is this step that seems the most mysterious of all. Marc D. Hauser, an expert on animal communication at Harvard, sees the uninhibited interaction between different neural systems as critical to the development of language. “For whatever reason, maybe accident, our brains are promiscuous in a way that animal brains are not, and once this emerges it’s explosive,” he said.
Richard Dawkins, in The Ancestor's Tale (and probably other places) notes that Cro Magnon humans at some point tens of thousands of years ago acquired something that led them to create, express, ritualize, and express themselves in ways that had been heretofore unknown for living things.
Although it seems that Neanderthals were not anywhere near chimpanzees in terms of intgelligence and organization, clearly the current dominant primate species "won" in terms of intellect, and probably communication, though possibly with brutal force as well. It is also becoming evident that our species has continued to evolve, and for all we know at the moment, this language capability might have been a relatively recent development.
It took millions of years to get to this point. It's important to keep in mind of just how incredibly fortunate we are to be living in this time, despite the crises we have now. Most generations of human existence were fraught with pain and terror and brutality that we have "managed." For whatever reason, we are able to communicate, and not just grunts and warnings of leopards, but the beauty of sonnets and our deepest loves and hatreds, our highest hopes and most compassionate dreams, and deepest despair.
So even when there is mistreatment, even when there is unreasonable infliction of suffering, the suffering itself is still a thing in which to be in awe.