Argument: Human clones will not reduce human biological diversity
Gregory Pence. "The Top Ten Myths About Human Cloning". Human Cloning.org - "3. Human cloning reduces biological diversity. Population genetics says otherwise. Six billion people now exist, soon to be eight billion, and most of them reproduce. Cloning requires in vitro fertilization, which is expensive and inefficient, with only a 20% success rate. Since 1978, at most a half million babies have been produced this way, or at most, one out of 12,000 babies.
Over decades and with such great numbers, populations follow the Law of Regression to the Mean. This means that, even if someone tried to create a superior race by cloning, it would fail, because cloned people would have children with non-cloned people, and resulting genetic hybrids would soon be normalized.
Cloning is simply a tool. It could be used with the motive of creating uniformity (but would fail, because of above), or it be used for the opposite reason, to try to increase diversity (which would also fail, for the same reason)."