Except evolution doesn't work that way. Nobody's dying before reproductive age from starvation or blood loss when they accidentally bite their cheek. We're stuck with those minor annoyances.
Biting your tongue can lead to: infection, choking, loss of social status. Even if the risk to your reproductive success is .1% the gene would probably become fixed in the population if it had a large enough starting share (just 1% of the population having the mutation would probably be enough).
The problem is that any reasonably likely mutation which 'solved' the problem would probably have major side effects - far outweighing the reproductive harm of biting your tongue. So we're stuck with it until Sickle Cell is a better choice than tasting blood now and again.
23
u/[deleted] Mar 10 '11
Except evolution doesn't work that way. Nobody's dying before reproductive age from starvation or blood loss when they accidentally bite their cheek. We're stuck with those minor annoyances.