if you're interested in this check out the coalescent theory, a very elegant mathematical model of population genetics: https://en.wikipedia.org/wiki/Coalescent_theory

The Coalescent, from a book by John Wakeley: http://www.faculty.biol.ttu.edu/olson/Molecular_Ecology_and_...

a good intro to population genetics by Hartl & Clark: https://www.amazon.com/Principles-Population-Genetics-Daniel...