Algae and bugs

One of my favorite books about the human tree of life and our ancestors is "The 10,000 Year Explosion" by Cochran and Harpending.  

We had our DNA analyzed four times.  Lynn is descended from many more branches of the human tree than I am, according to 23andMe.

I think that people who are confident they are higher quality would be unhappy to grasp that all humans descended from Africans.  I think it is something of a joke on me to picture my biological forerunners being blue-green algae and cockroaches.  I admit that I haven't studied human development enough to know how possible it is that my biological development could, in fact, include algae and insects.  Deeply, I don't care.