Quote from Sting_Auer
All animals coming from eggs?
Even though I haven't heard of that anywhere else, that is an epic idea. Making animals passively and automatically reproduce, would cause extreme overpopulation in the wild. Having all animals come from eggs is, for one, completely original, and two, makes animals only reproduce in controlled condition.
Me gusta cow eggs.
it's not original, it's used in every game that involves breeding (pokemon, viva pinata, etc).