basil,do you plan on editing the post? not to be rude, but I have some ideas too, one that starts with a wanderer, so a tribe invites a wanderer in they breed, but are low on food, they produce twins and send them away one is female, and acts like a wanderer, they start with one gem and 30 food on a jungle island with some genes suited and half not suited to the enviroment, the other tribe is slightly newer and acts like the home island tribe but they wont recognize you until you get to the 20eth generation, and 100th day, they also travel on ports, going to a killer island to populate and act like a home island tribe on, meanwhile, the babies are at the beach and get swept away by a tsunami. also the wanderer could be blind but add a new gene called injured eye that when breeded acts like a normal eye but gives no seeing.