By CARL ZIMMER - DISCOVER MAGAZINE
Added: Thu, 20 Oct 2011 16:46:30 UTC

It is a shame that grammar leaves no fossils behind. Few things have been more important to our evolutionary history than language. Because our ancestors could talk to each other, they became a powerfully cooperative species. In modern society we are so submerged in words—spoken, written, signed, and texted—that they seem inseparable from human identity. And yet we cannot excavate some fossil from an Ethiopian hillside, point to a bone, and declare, “This is where language began.”

Lacking hard evidence, scholars of the past speculated broadly about the origin of language. Some claimed that it started out as cries of pain, which gradually crystallized into distinct words. Others traced it back to music, to the imitation of animal grunts, or to birdsong. In 1866 the Linguistic Society of Paris got so exasperated by these unmoored musings that it banned all communication on the origin of language. Its English counterpart felt the same way. In 1873 the president of the Philological Society of London declared that linguists “shall do more by tracing the historical growth of one single work-a-day tongue, than by filling wastepaper baskets with reams of paper covered with speculations on the origin of all tongues.”

A century passed before linguists had a serious change of heart. The change came as they began to look at the deep structure of language itself. MIT linguist Noam Chomsky asserted that the way children acquire language is so effortless that it must have a biological foundation. Building on this idea, some of his colleagues argued that language is an adaptation shaped by natural selection, just like eyes and wings. If so, it should be possible to find clues about how human language evolved from grunts or gestures by observing the communication of our close primate relatives.

This line of thinking raised an exciting possibility: Perhaps language left a fossil record after all—not in buried bones, but in our DNA. Yet for years biologists could not find a single gene involved in language.

Ten years ago, that finally changed.

Read on

TAGGED: GENETICS