Question: Why do people speak different languages?

Ciarán O'Brien answered on 21 Nov 2014:

Language evolves, a lot like life! 🙂

Imagine two countries a long time ago that spoke the same language. People in different countries are separated by a lot of distance, and a long time ago there was no internet, and most people couldn’t read or write to send letters, so very few people would have been able to meet their neighbors in the next town, never mind people in another country.

Then something interesting happens in Country A. Let’s say a man called Gunther Weiss did something really stupid and made an absolute fool of himself in public. People talk about it, but very few people can write about it so nobody outside the country knows. “Pulling a Gunther Weiss” becomes a popular phrase whenever someone embarrasses themselves. Eventually people in Country A start saying they’ve Weissed for short.

Back in Country B, Nobody is even called Gunther, never mind Gunther Weiss. They have no what someone means when someone says they just weissed. It’s a completely new word they don’t understand.

Now, give Country A another 2-300 years of people like Gunther embarrassing themselves, or doing something heroic, or new inventions changing how the people live. Country B still doesn’t hear about these things because very few people can read and write, and news travels very slowly. That will generate a lot of new words, or different ways of saying old words. People in Country A are used to these words, they’ve become commonplace, but to people in Country B, they’d barely understand what anyone in Country A was saying any more!

Of course the same thing has been happening in Country B, but with different people, places and ideas, so while both countries spoke the same language, both have gone in different directions and have very little in common any more. This is pretty much why people speak different languages. individual words can change their meaning or sound, and new words get created, and the language changes slowly. It’s a lot like mutation in living creatures, only instead of changing DNA, it’s the words that are changing.

Here’s a tree diagram showing how some languages are related:

And here’s a tree diagram showing how some dinosaurs are related. Notice the similarity?