If we ever make contact with intelligent aliens, we should be able to build a universal translator to communicate with them, according to a linguist and anthropologist in the US.

Such a "babelfish", which gets its name from the translating fish in Douglas Adams's book The Hitchhiker’s Guide to the Galaxy, would require a much more advanced understanding of language than we currently have. But a first step would be recognising that all languages must have a universal structure, according to Terrence Deacon of the University of California, Berkeley, US.

How language develops is highly controversial. Some theories argue that the process has been built into the human brain through evolution, and that the sounds we use to communicate are arbitrary.

If that is true, there could be an infinite set of possibilities for expressing an idea through language. An alien race that developed through a completely different process of evolution would probably speak a language indecipherable to humans.