
The thing about evolutionary biology is that researchers can't help providing evidence for it. It's not intentional; it's not as though there is any doubt, it's just that the reality is that species evolved from common ancestors. So, inevitably, reality shows the evidence.
Take, for example, this piece of research published yesterday on the subject of bonobo (Pan paniscus) and chimpanzee (P. troglodytes) and their use of non-verbal communications or gestures which both use extensively to communicate with others of their species.