Language and Cultural Evolution

Ed Yong has an excellent summary of a new experiment simulating the natural evolution of an artificial language as it's passed from one person to another. Every time we use a language we are subtly bending the rules and words to fit the contours of the brain:

Together with Kenny Smith at Northumbria University, they have provided the first experimental evidence that as languages are passed on, they evolve structures that make them easier to transmit effectively.

The team tracked the progress of artificial languages as they passed down a chain of volunteers. They found that in just ten iterations, the made-up tongues had become more structured and easier to learn. What's more, these adaptive features arose without specific plans or designs on the part of the speakers. The appearance of design without the guiding will of any designer is another trait that offers compelling parallels to biological evolution.

This experiment reminds me of some fascinating studies done on deaf children in Nicaragua. Until the early 1980's, the deaf citizens of Nicaragua remained tragically isolated. The country didn't have a sign language, and deaf children were confined to overcrowded orphanages. However, when the first school for the deaf was founded in 1981 the situation immediately began to improve. The children were never taught sign language (there were no teachers), but they suddenly began to speak with their hands. A makeshift vocabulary seemed to spontaneously evolve.

But the real transformation occurred when younger deaf students were introduced to this newly invented sign language. While older students were forced to converse in relatively imprecise terms, these second generation speakers began to give their language a structure. No one had taught them grammar, but they didn't have to be taught: the young children automatically imposed their innate knowledge onto their growing vocabulary. Verbs became inflected. Adjectives became distinct from nouns. Concepts that older speakers represented using a single sign were now represented by multiple signs enclosed within a sentence. Although these Nicaraguan children had never known language, they invented their own.