What are the premises in the model?
• In terms of viviparous animals, there are only four steps in the model: 1) Formation of fraternal zygotes in these opposite genders. 2) Similar gross mutations on these zygotes. 3) Self-replication of those zygotes. 4) Development of these zygotes and birth of a group of baby in both genders, and mating among the siblings after they mature. Step 1, 3 are natural phenomena, occur every day; step 4 is also a natural phenomenon that can be observed in many animals. Only step 2 is a premise, which suggests fraternal twins zygotes with the similar gross mutation by chance.
