Individuals I-1 and I-2, along with the married couple II-5 and II-6, decide to move to a deserted island and start a community that would likely have a higher frequency of individuals who either have the disorder or carry the allele for the disorder than most other areas of the world. This is an example of:

Read the aphorisms. be slow in choosing a friend, slower in changing. an open foe may prove a curse; but a pretended friend is worse. a true friend is the best possession. according to these aphorisms from benjamin franklin's poor richard's almanack, what might happen if a person is careless in choosing a friend? it is best not to have friends because they will usually betray you. casual friends are often the best and can be more trusted than enemies. a person who has betrayed you can sometimes become a good friend. a friend who is not carefully chosen can be worse than an enemy.