When will all mankind look the same?

Because we have short lives, it is easy for us to assume the world has always been the way we see it today. Only education in history and in science can overcome this failing.

We take it for granted that there are ethnic groups who look different. However nothing about this is pre-determined.

I made this the topic for my 40^th "Thought for the Week" on BBC Radio Manchester this morning. You can read it below.

Thought for the week

Last week, I agreed to speak at Manchester Metropolitan University. The talk will be next February, on the topic: “How immigration has changed Manchester in the 65 years I have lived here.”

That got me thinking about how mankind has changed in the last 200,000 years. That is roughly when our ancestors left Africa to spread around the world.

Simple evolutionary adaptation led to people in different places having slightly different genes. For example, white skin helps you in Iceland, where there is little sunlight. It saves you getting rickets from a lack of vitamin D.

Conversely, the humans who became Australian aborigines kept their dark skins. That saved them getting skin cancer in the strong Australian sunlight.

Throughout human history, most people lived and died within about 20 miles of where they were born. In 200,000 years, there was plenty of time for genetic differentiation.

Today we live in a different world. Travel is easy. For example, my wife and I live about 4,000 miles from where we were born in Pakistan. Our second son lives in America.

Because of technologies such as vitamin D tablets and sun-cream, we don’t need to have different genes for different places like we did before.

“How long before the genetic mixing from intermarriage means that people everywhere look the same?” My guess is less than 1,000 years, and, if anything, I think I am being cautious.

There is nothing pre-determined about genetic differences. Genetic differences exist for a reason, and when the reasons go away, so will the differences.