Birth control.
Sex for a female is now free, so she is not as selective. This is bad news for human fitness, but is not likely to change.
Sex for a female is now free, so she is not as selective. This is bad news for human fitness, but is not likely to change.
Remember, though: This is a hypothesis, no data. Consult your friendly neighborhood sociologist, who will tell you that the world is more complicated than that. Consider, for example, that not everyone in America is in the same social class...
As to human fitness - I expect that we'll widely use gentech before that becomes an issue [1], and anyway I think "smart/succesful people have fewer kids" would be a bigger issue than slightly less careful mate selection, if indeed modern females are less careful in selecting a mate (I doubt it.)
[1] This is a prediction, not a value statement. I think it's a good idea, but I'm somewhat squeamish.
Doesn't that confirm what I said? She can't just marry whoever she wants, she needs to very carefully pick.
Edit: I see your clarification, and I'm not so sure it argues against me. Her first choice is (presumably) a romantic choice, but instead she must choose the practical choice. I would assume the practical choice is fitter.
That would be even worse. Whatever our notion of fitness would be, it's definitely different from nature's needs. If anything, gentech would make fitness worse before making it better.
Increased female reproductive choice (of whether and with whom to mate) yields an upward trend in fitness because it results in fewer, better cared for offspring.
It takes a lot longer than that, and it would be impossible to measure due to birth control being correlated with medical care.
> ...yields an upward trend in fitness because it results in fewer, better cared for offspring.
The level of care to an offspring has no effect on its genes, and if anything can mask genetic weakness by substituting extra care. So it does not cause an upward trend for the children of the offspring.
Interestingly one trait that is being selected for is female non-sensitivity to hormone contraceptives. Now that would be interesting to measure.
Another trait that is theoretically being selected for is behaviors that would discourage contraceptive use (physical or hormone based), but I doubt that that would be measurable - at least not for many more generations.
It's an interesting world we've made for ourself, I would love to see demographics for 250 years from now.
They're outpopulating us. That's more or less all that Darwinian fitness boils down to.
Meanwhile, in Africa, human beings are evolving resistance to AIDS:
http://en.wikipedia.org/wiki/HIV_disease_progression_rates#H...
In the end, males and females are mating, so there is selectivity going on as before in terms of choosing who you want to father/birth your children.
The introduction of birth control could be said, though, to reduce the impetus for selectivity with regard to sex, but not mating.
Even if they would have never chosen that person in the first place (for mating) if they were more selective at the outset.
Either way, I think that you can just as easily say that a woman is more likely to leave a "bad" candidate for mating, since she is not tied down by the presence of offspring.
I guess we'll just have to see :)