Are Mutations Harmful?
It would depend upon the mutation and the surrounding circumstances. Some can be both beneficial and harmful. One example of that is the group of mutations that gave rise to sickle cell anemia. It’s disadvantageous as it can result in the death of the unlucky recipient. Then again, it usually doesn’t. And it happens to promote resistance to malaria. Therefore, as long as it hasn’t killed you and you live in a place where malaria’s a danger, it’s advantageous. Malaria-prone places include large tracts of Africa, and this kind of condition arose within the populations living there. It was certainly beneficial to the viability of those populations. However, lots of people were kidnapped from Africa and forced into slavery elsewhere. Others left for further reasons. This all means there are now lots of descendants of those people living in places without the risk of malaria. In those circumstances sickle-cell disease supplies all its potential disadvantages and its potential benefit became