I feel that over time people might be prone to do certain things over other things. Over time if we keep getting lazier and lazier and more and more addicted to our phones and electronics, we might just cut everything else out in the world. I would consider that evolution because people are evolving over time to like certain things over other things. People might neglect things like Shelter, Food, and a decent relationship to be entertained. People also might take other peoples examples like doing challenges are influencing people to make decisions for short lived fame, and all of this is because of human evolution turning into lazy people or wanting fame.
This is because a sample is supposed to ideally represent the whole population from which it was taken. Taking samples from different location within the population ensures that they are no bias in the sample. Each part of the population should be well represented in the sample so that the conclusions drawn from the sample represent the properties of the whole population.