Nicholas Wade today covers a new study by Wolfgang Enard and colleagues, in which they generated transgenic mice expressing the human-derived version of FOXP2.
Naturally, the mice squeak differently.
In a region of the brain called the basal ganglia, known in people to be involved in language, the humanized mice grew nerve cells that had a more complex structure and produced less dopamine, a chemical that transmits signals from one neuron to another. Baby mice utter ultrasonic whistles when removed from their mothers. The humanized baby mice, when isolated, made whistles that had a slightly lower pitch, among other differences, Dr. Enard says. Discovering that humanized mice whistle differently may seem a long way from understanding how language evolved. Dr. Enard argues that putting significant human genes into mice is the only feasible way of exploring the essential differences between people and chimps, our closest living relatives.
Interestingly, the human version fills in “perfectly for the mouse version in all the mouses tissues except for the brain.” Well, I suppose that is to say that there are no measured changes in other tissues where FOXP2 is expressed.
I pointed to a study of FOXP2 knockout mice in 2005, and that study is mentioned here as well.
Meanwhile, if you want to hear mice squeak, the Times includes an audio file. Oh, and the Stuart Little element:
People shouldnt think of this as the one language gene but as part of broader cascade of genes, [Gary Marcus] said. It would have been truly spectacular if they had wound up with a talking mouse.