Islands play a key role in fostering language diversity

Despite covering a small fraction of the world's land, islands have had an outsized impact on biological sciences, demonstrating evolution in real-time. A classic example is the Galapagos Islands, which played a crucial role in shaping Charles Darwin's understanding of evolution.

ANU biologists sought to explore whether islands influence language change and diversity in a similar way. To investigate this, they compiled a database containing languages spoken on over 13,000 inhabited islands worldwide.

Professor Lindell Bromham, an ANU evolutionary biologist and lead author of the study, highlighted that nearly 20% of the world's languages are spoken on islands, even though islands constitute less than 1% of Earth's land area.

"Islands are evolution's laboratories. To Darwin, islands were a microcosm of the processes of change that occurred everywhere," she explained. "We were curious why islands capture so much of the world's linguistic diversity. When we analyzed the global database, we found that islands play a similar role in generating language diversity as they do for biodiversity."

The researchers found that the number of island-specific languages increases with both the size of the island and its distance from the mainland.

"Around 10% of languages are endemic to islands, used only, or predominantly, on islands," Professor Bromham noted. "Island languages also show distinct patterns of evolution, with languages spoken predominantly on islands having significantly fewer phonemes, the basic sound units from which words are made."

This study builds upon previous research that examined global trends in language diversity and the risk of language extinction. That earlier research revealed a concerning loss of linguistic diversity, with more than one-third of the world's languages considered endangered, and as many as 1,500 languages potentially disappearing by the end of the century.

"Our analysis shows that island endemic languages do not have significantly higher levels of endangerment than their mainland counterparts," said Professor Bromham. "But because islands hold such a disproportionately large share of global language diversity, they will play a crucial role in safeguarding linguistic diversity."

She concluded, "Islands are not only cradles of linguistic diversity but also arks carrying language diversity forward into the future."

Research Report:Islands are engines of language diversity