Slugs, crows and the French

Editor: Most people seem to regard language use as a uniquely human behavior. What’s the difference between animal and human languages?

Author: There's a distinction between signaling systems and what we call languages. A traffic light with red and green lamps is a signaling system. Red = stop. Green = go.

Editor: And language use might be turn left at the next light, there’s a teashop, their organic apricot muffins actually taste quite decent?

Author: Fair enough. So let’s say many animal species do have signaling systems. Some are quite rudimentary, like those used by slugs or sponges. Other species might have more extended systems like those used by crows, cats or chimpanzees.

Editor: Slugs stop at traffic lights?

Author: Admittedly, slugs are not highly sociable. An antenna waved, a waggle in the slime trail perhaps.

Editor: And crows?

Author: Listen to them. Watch them. They have signaling systems. Some say even unique to local crow communities. So a crow living in the U.S. might not understand a crow from France.

Editor: If it could fly that far. Speaking of the French… human languages…

Author: Not everyone would agree…

Editor: Now, now.

Author: Humans signal too. We turn red, wave our arms. We use persuasive expressions like “I’d suggest…” or we use words like “by the way,” to signal a topic shift which is something not even chimpanzees do. But more than that, we use language to tell stories and discuss ideas. So we've made this big jump, we've gone from signaling to communicating through language. And the French have actually always been pretty good at that. They've always practised a lot.
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