Adaptive evolution in the human genome

Okay kiddo, so you know how we humans have different colors of hair, eyes, and skin? This happens because of evolution. Evolution is when our body changes over time to help us survive better in the environment we live in.

Adaptive evolution is a specific type of evolution that helps our body change in ways that are really helpful for us to survive in our environment. So, let's say a long time ago, people lived in an area where there was a lot of sunlight. Those people with darker skin could survive better because their skin had more melanin, which is like a natural sunscreen that protects them from the harmful rays of the sun. So, over time, the people with darker skin passed on their genes to their children, and this became more common in that area.

Similarly, some people might have genes that help them digest certain foods better or resist certain diseases better. Over time, if those people are able to survive and have babies more easily because of these helpful genes, then those genes become more common in the population.

Basically, our body changes over time to help us survive better in the environment we live in, and sometimes those changes are really helpful for us. That's adaptive evolution in a nutshell.