What Can Genes Tell Us About Fitness?
https://www.scientificamerican.com/article/what-can-genes-tell-us-about-fitness/
Several years ago, I received a tiny plastic test tube in my mailbox, so naturally, I spit in it and put it back in the mail. No, this was not an elaborate practical joke, I was actually submitting my DNA to a testing service called 23andMe.
A few weeks later, I received a report telling me all about myself, based on what they found in my genes that were contained in that saliva I put in the mail. There was information about my ancestry, my hair and eye color, some of my health predispositions and risks, and even what percentage of me is directly linked to Neanderthals (more than I would care to admit, to be honest).