A few interesting bits regarding language that came before my eyes recently:
First a new study reveals that the "Putty-nosed monkey" (Cercopithecus nictitans) monkeys can combine simple primitive calls into more meaningful sequences. The evolution of grammar?
Second, studies of prairie dogs show that they have "the most sophisticated communication system that anyone has shown in animals", including a capability to create new terms for things they've never seen before.
Finally, this article discusses the theories of Steven Mithen, professor of early prehistory at the University of Reading, that early hominids ancestors had a musical culture that strongly influenced the development of language.