What he proposed next was the principle of segregation, also became known as the law of segregation or Mendel's law of Segregation. Now, what he argued was that whenever the gametes are formed before we actually have the mating process take place, the two genes that code for that same trait. In this case, the height behave like particles and actually separate. During the process of gamete formation. So to see what we mean, let's take a look at the following diagram. So, before they can combine to actually form the offspring, both of these must actually segregate.