What is fitness?

[Timothy_Horton]

@thoughtful

But wow that first video already I have a lot of problems with. It seems like a very confused version of Medelian genetics. Can we have an example of a trait natural selection actually acts on?

Here is a great example we discussed last year.

The Rock Pocket Mouse: A Model for Natural Selection

I thought it would be helpful to use a specific example of natural selection for those having issues understanding how it works. Coat color in pocket mice is one of those examples. The paper I will be working from is found here: First, let’s look at the environment where these mice are found. They are found in the southwest deserts of the US, and the vast majority of their range is made up of light brown dirt and rocks. However, there are isolated areas where recent volcanic eruptions have created areas with dark black basalt rock. Interestingly, when we look at the distribution of coat color in pocket mice it matches the environment they are found in: [image] The black mice are found in islands of black basalt rock, and brown mice are found in the sea of brown desert between those islands of volcanic rock. I don’t think it is a stretch to state that camouflage is playing a strong role in the distribution of coat color alleles. The scientists in the paper also looked at in…