Of the many compelling arguments made in Mark Pagel’s TED talk How Language Transformed Humanity, one of the most fascinating is the idea of genetic preservation through language.

Some people would argue that over the course of human history, evolution has slowed down in our species. Long ago our ancestors may have passed up someone who was visually impaired, or lazy. Now, it seems that almost anyone will mate with almost anyone – except for one thing.

We tend not to procreate with people with whom we don’t share a language. Think about that – two intellectual and physical equals, both naturally selected for the fittest traits, still have very little chance of combining their genes because they can’t talk to one another.

It would seem that Evolution has a reason for us to keep our genes in our language group. But what could that possibly mean?

According to Mark Pagel, who is a professor of Linguistic and Behavioral Evolution at Reading University, the rise of language in humanity goes a little like this:

• Chimps had the intelligence to use tools, but they didn’t have the social learning trait to share information.
• Neanderthals had social learning, so they could copy what they saw another neanderthal doing, but they couldn’t speak about it to cooperate. They only had the skills they could steal from someone else, and remained competitive.
• Homo sapiens had language, and could build a shared wealth of knowledge. This cooperation led to an explosion of creativity and the ability to manipulate their environment. Therefore, homo sapiens could spread their population all over the world, no matter the climate.

With all that expanding, humans developed separate languages. Yet Pagel reminds us that presently, the denser the human population, the more languages that arise. There almost 1,000 languages spoken in Papua New Guinea, population 7 million.

Why would a dense population need multiple languages, but a sparse population is happy to communicate with one another? Humanity must need to strike a balance between sharing information and protecting a gene pool. It would seem that distinct languages draw rings around cooperative groups, slowing the flow of genes and protecting those linguistic populations.

Pagel says language is the voice of our genes. Many linguistic theories point to separate language groups sharing separate ways of thinking. So, could it be that distinct language groups have distinct, subtle genetic codes worth preserving, and worth protecting via distinct language?

Listen to his TED talk – your mind will race!