You are walking through the woods in Spring and the branches are loud with birdsong. Then you open a translation app on your phone and you can hear every word the birds are saying.

Perhaps this sounds unlikely. But scientists are now using computer technology to understand how animals communicate.

For instance, greylag geese have at least 10 different calls. Moustached warbler chicks will jump or duck depending on different kinds of warning cry. Superb fairywren mothers sing to their eggs, and have a distinctive song for hatching chicks.¹

Scientists have started using machine learningA field of artificial intelligence that aims to use data to teach machines to "learn" for themselves without the need for specific programming. to recognise different types of birdsong. The Merlin app can identify 1,400 different species of bird. Animal-communication expert Mike Webster, who helped develop the app, claims "a lot of people have dreams of using AI to allow us to decipher what animals are saying".²

But most scientists draw a line between language and communication. Birds, dogs, cows - they make sounds to communicate. Language is related to thought, self-expression, even self-consciousness.

According to the language researcher Robert Berwick, it is best to think of language "not as speech but as a cognitiveRelating to the processes of thinking and reasoning. ability in the mind that sometimes leads to speech".³ And public intellectual Noam Chomsky argues that the idea animals - even close relatives like chimps - could learn language is "totally meaningless".⁴

The 20th-century philosopher Ludwig Wittgenstein said that: "If a lion could talk, we could not understand him."⁵ The problem is not the different sounds animals and humans make, but the different worlds we live in.

Thanks to apps like Merlin, more and more people are learning to identify birds. Even if we never learn to speak with the animals, it is still worth listening to what they say.

Do animals have language?

Yes: Computer analysis is starting to show the complex ways that animals communicate. People only refuse to call this language because they want to make humans seem special.

No: Language does not simply require communication, but also complex thought and self-expression. The instinctive calls made by birds cannot be compared to human speech.

Or... Even if we could translate animal speech, we will never share the worldview that it expresses. But animal communication is worth studying for its own sake.

Machine learning - A field of artificial intelligence that aims to use data to teach machines to "learn" for themselves without the need for specific programming.

Cognitive - Relating to the processes of thinking and reasoning.