Mutant Gene Responsible for Speech?

An anonymous submitter writes: "A new study published in Nature reports that humans developed speech and language 200,000 years ago as a result of gene mutation. Washington Post story with more background. The mutation in the FOXP2 gene allowed humans greater control over their mouth and throat muscles, and gave them the ability to produce new sounds. It was apparently such an advantageous mutation that it quickly swept through the human population (10,000 - 20,000 years) almost entirely wiping out earlier versions. This development seems to also match up closely with the time period humans began developing culture. Researchers next want to try altering the gene in mice to see what happens, although they suspect there are many other genes involved. So, how long until I can get a talking dog?"

Comments

Parrots?

[Quixote]

Parrots can make most of the sounds that humans can make ( and then some). Does that mean parrots can "speak" like humans, or develop a culture? I don't think the ability to make sounds has anything to do with culture.

Most geneticists don't really believe that...

[Apogee]

I wonder if you read the article?

No halfway modern geneticist nowadays believes that there is a single gene responsible for more than the most simple of traits. And I had the impression that the Nature article linked from this story expresses that view quite clearly with statements like:

Finding one gene is like finding one part of a car. It looks useful, as though it's part of a larger mechanism. But we don't know what it does, what other parts it interacts with, or what the whole vehicle looks like. "It's an unbelievably complex system, and we've got one tiny glimpse," says Michael Tomasello, a psychologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

A very nice explanation on the limited usefulness of trying to assign "the" function for a particular gene was proposed in the book The "Collapse of Chaos : Discovering Simplicity in a Complex World" by Jack Cohen and Ian Stewart, a molecular biologist and a mathematician, respectively.

In general, it is easy to remove one part from a network of interacting parts, and observe the mechanism breaking down. Naively, these parts are then called the "key regulators" of this or that phenomenon, be it speech or whatever. Only lengthy experiments will then reveal the whole underlying mechanism maybe.

The stance that you attribute to geneticists, that they expect simplistic, monogenetic solutions to complex problems is actually more caused by the press (not only laymen's journals, btw), which always go for a snappy headline without "maybe" or "can be a part of a complex mechanism".

just my 2 centimorgans :)

Speech != language

[mrogers]

What kind of competitive advantage would speech have offered for early humans, if language did not already exist? Language consists of much more than the production of words. You also need to be able to parse sentences, to "reverse-engineer" the grammar of your parents' language before you can start producing sentences of your own. This raises the question of whether parts of the brain have evolved "for" grammar (a hypothesis supported by Noam Chomsky and argued by Steven Pinker in his excellent book The Language Instinct ), or whether existing pattern-recognition and planning mechanisms turned out to be useful for language, influencing the form and scope of all subsequent languages (suggested by Mark Steedman among others).

It's even possible that complete languages existed before humans were able to speak. American Sign Language is an example of a language with its own complete, unique grammar and morphology, which does not make use of speech. (See Pinker's book again.) Its existence supports the hypothesis that the parts of the brain responsible for language can operate independently of the parts that co-ordinate speech. In summary, there is a lot more to language than co-ordinating the muscles of the mouth and throat.