Language diversity is greater in long narrow N-S oriented countries than wide E-W ones.
Researchers at Stanford University analysed the percentage of historically indigenous languages that remain in use in 147 countries today relative to their shape. For example, the team looked at the difference between Chile, which has a long north–south axis, and Turkey, which has a wider axis running east to west.
The researchers found that if a country had a greater east–west axis than a north–south one, the less likely it was for its indigenous languages to persist.
Continents that span narrower bands of latitude have less variation in climate, which means a set of plants and animals that are adapted to more similar conditions. That means that agricultural innovations are able to diffuse more easily, with culture and ideas following suit.
The Stanford researchers used language persistence as a proxy for cultural diversity in their study.