Languages are a lot like living organisms. Both evolve over time, allowing an ancestral tongue like Latin to sire diverse descendants — Spanish, French, Romanian — that are more closely related to each other than to, say, Korean. This much is old news; Charles Darwin himself noted the resemblance. “The formation of different languages and of distinct species,” he writes in The Descent of Man, “are curiously parallel.”
Now, new research shows that the analogy runs deeper. Islands, long recognized as hotbeds of biological diversity, are just as much engines of linguistic diversity. Drawing on a global database of languages from more than 13,000 inhabited islands (with a size cutoff at about 4,250 square miles), researchers at the Australian National University discovered that some of the same evolutionary patterns hold true in both life and language.
Incredibly, although these islands make up less than 1 percent of Earth’s inhabited land, the study found that 10 percent of languages are endemic to them — spoken nowhere else. Compare that to Russia, where the ratio is exactly reversed — 10 percent of the world’s landmass, with a little over 1 percent of its languages. As lead author Lindell Bromham put it, islands “capture a disproportionate amount of both biodiversity and language diversity.”
Biologists solved the first half of that mystery long ago, so Bromham and her colleagues (all of whom come from the life sciences) decided they’d take a stab at the second half. “We in evolutionary biology,” she says, “have spent decades building up a suite of analytical tools to answer those kinds of questions.”
