It is widely held that man is the only creature with language. But that may not be true.
African vervet monkeys are always looking around for danger, and when they perceive a threat, they give an alarm that is specific to the threat.
If it’s an eagle, they give an eagle alarm, and all the vervets take up the cry, and take cover under the trees.
If it’s a snake alarm, the vervets do the opposite. They climb up into the tree repeating the call — Snake! Snake! Snake!
If the sentry monkey spots a leopard, it makes the leopard cry, and the vervets likewise leap into the tree, only this time they go out onto the narrowest, most lightweight branches — the perfect place to be when being pursued by a 200 pound cat.
Robert Seyfarth and Dorothy Cheney of the University of Pennsylvania have even stimulated these responses in vervets using alarm call recordings.
I think it’s pretty clear that African vervets have a language. Their vocabulary may be limited, but their cries perform the same task that our presentations are meant to perform: They get their listeners to pay attention, solve a problem, and DO something specific.