Humans aren’t the species that strive for efficiency when communicating with a new study finding dolphins do it too.

It’s the first evidence that another species follows one of the basic rules that defines all human languages: the law of brevity.

The work which is just one step in a larger attempt to understand the evolution of communication, also suggests that human might not be as special as we like to think we are.

“Indirectly, this is telling us something about us” says Dr David Lusseau, a behavioral ecologist at the University of Aberdeen, in Scotland.

“More broadly, it is helping us understand how you get to this level of complexity. Is there only a limited way to reach it or can you reach it in many different manners?”

In their long-term quest to understand how complex communication systems developed, Lusseau and colleague Ramon Ferrer-i-Cancho chose to study dolphins because the animals are far removed from humans on the evolutionary tree.

They diverged from us 65 million years ago, and their brains are built differently from ours. At the same time, dolphins are known to communicate with a repertoire of about 30 non-vocal behaviors.

For example, when one dolphin performs a side flip or a series of side flips, for example, the rest of the group stops what it’s doing and move on something else. Scientists aren’t sure if the side-flipper is expressing a desire or an order. Still, the message gets across.