Regardless of how one understands our relationship to the animal kingdom, many of us are interested in what distinguishes us biologically from animals, especially the animals most similar to us: chimpanzees, gorillas, and the like. Thanks to genomics and widely quoted numbers like 98% genetic similarity between humans and chimps, DNA becomes central to how we answer that question. One gene that has become popular to mention in that conversation is FOXP2. There is evidence linking FOXP2 to language, and of course language is one of those traits where humans really stand out. Buffalo buffalo may buffalo Buffalo buffalo, but they’re not getting any people to believe they can even utter such a sentence, let alone parse or diagram it.
Our gift for gab is multi-faceted. On the cognitive side, we can associate words (or the collection of sounds we hear as a word) with abstract ideas, going well beyond any direct mapping between physical objects and the noises they make. Anatomically, we have the ability to make a wide range of vocalizations that we can mix-and-match into a rich set of words. Some or all of these distinctive traits are likely to have a genetic basis, which can be explored by looking at where our genomes differ from those of other animals.
Enter FOXP2, a gene that has been linked to significant language impairment when it is mutated. It is also associated with the ability of songbirds to learn their unique tunes. For these and other reasons, we believe it plays some part in our linguistic abilities. At the same time, our version differs from the chimp version by just two amino acids. That kind of difference can mean the world biologically, yet it is still challenging for many to think that such a subtle change has unlocked such a profound gift.
An initial investigation into the history of FOXP2 suggested that it had been strongly selected for, implying that it played a significant role in human evolution. Our verbal talents were not merely distinctive, they made us successful. But now a new study (crucially, including a more globally representative sample of human subjects) has cast that particular conclusion in doubt. That particular gene no longer appears to bear the hallmark of a strong selective advantage. That doesn’t mean it offers no benefits, or that it played no role in human development, just that the story of FOXP2 is not as straightforward.
I bring up this story mainly because, as I said, FOXP2 comes up a lot in conversations about human uniqueness, and the related topic of the image of God. There are a lot of different angles one can take with it: just a small amino acid accident is all that keeps us from being reduced to simian grunting; look what just a tiny but finely-tuned changed can accomplish to set us apart; language made us human; the cognition of language can’t possibly be just in the brain if such a tiny difference separates us from chimps; and so on. A finding like this can help calibrate those angles a bit, reminding us that there is still a lot we don’t know about FOXP2 and more broadly about the biology of language. Some skepticism about why humans evolved they way they did, even if one accepts the how of it, is also warranted. That we have language skills unlike any other creature is clear and indisputable, and likely also what makes it possible for us to conduct research on FOXP2 when no other animals do. Our theology is likely better off focusing there rather than on the nuances of our still-developing understanding of the underlying genetics.
Interested in language? Then you might enjoy this week’s conversation on Faith across the Multiverse about the role of translation in working across disciplines, whether that’s biology and computer science, or science and theology, or storytelling and science, etc.