Some females hit puberty as early as 7--is this a "canary in the mine shaft" kind of thing?

“You can blame chemicals or even obesity..” from coalspeaker:

But either ways girls are developing breasts by age 7 or 8 and going through puberty a lot earlier in life..

In the past, I’ve read about how the number of females born goes up during troubled times. This makes sense from an evolutionary perspective as it only takes one male to impregnate many females.  During times of stability, the birthrate of males goes up.

What if females reaching puberty younger is an evolutionary tactic to defend against an, as yet, unseen instability with humanity?  What if humanity, itself, is failing and this is our genetically instinctive attempt to combat that process of failure?  Females hitting puberty earlier means they can get pregnant sooner in life.  Assuming menopause doesn’t hit earlier, as well, this allows them to extend their child-rearing years, thus giving humanity a better shot at survival.

Is humanity under attack from something that is causing it to fail?  I don’t think so.  I think the effects of humanity’s internal flaws are starting to be felt on a genetic level.

Too bad one of those internal flaws of humanity is an inability to recognize slowly boiling water.

Remember that story about the frog?

I’m not necessarily pointing at Global Warming, either.  We’re facing a lot of challenges that most of humanity is just to frightened to face.