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Evolution's Path May Lead To Shorter, Heavier Women
Hugh Pickens writes "Yale University researchers believe that if evolutionary pressures of sexual selection and reproductive fitness continue for another 10 generations, the trends detected in their study may mean that the average woman in 2409 AD will be 2 cm shorter, 1 kg heavier, will bear her first child five months earlier, and enter menopause 10 months later. 'There is this idea that because medicine has been so good at reducing mortality rates, that means that natural selection is no longer operating in humans,' says Stephen Stearns of Yale University. 'That's just plain false.' Stearns and his team studied the medical histories of 14,000 residents of the Massachusetts town of Framingham, using medical data from a study going back to 1948 spanning three generations, and found that shorter, heavier women had more children than lighter, taller ones. Women with lower blood pressure and cholesterol were also more likely to have large families as were women who gave birth early or had a late menopause. More importantly, these traits are then passed on to their daughters, who also, on average, had more children. The study has not determined why these factors are linked to reproductive success, but it is likely that they indicate genetic, rather than environmental, effects. 'The evolution that's going on in the Framingham women is like average rates of evolution measured in other plants and animals,' says Stearns. 'These results place humans in the medium-to-slow end of the range of rates observed for other living things.'"
Give that idiocracy shit a rest. It's not genetically dumber people who make more children, it's people lower on the social scale. As in, people in ghettos and immigrants. Poor education and poor nutrition (both which cause lower IQs) aren't genetically hereditary.
So-called smart people always confuse uneducated people with less intelligent people. Maybe they're not that smart after all.
You just got troll'd!
There's no need to bring Rush Limbaugh into this.
It's not universally true, but it is more or less an accepted fact.
Fertility rates are inversely proportional to income.
In the modern world there are a lot of reasons for this. The rich tend to have access to better education. therefore, they tend to try to start a career before a family (illustrated in comedic fashion by the Mike Judge movie Idiocracy). Then with their career dominating their lives, they usually only have a couple kids at the most.
More wealthy folks have better access to birth control. Again, better education plays into this. On the extreme end of the spectrum, you have folks who have superstitious beliefs. That doesn't help keep their fertility rates down any...
Economists and demographers have known about this correlation for centuries. And it's interesting because it goes across religions, across nationalities, race, and other factors. Poor Americans are just as likely to have a higher fertility rate as poor French, or Japanese. Poor Nigerians or Indians are even more likely because a poor American is fairly well off by Nigerian standards.
Side Rant: The Israelis in particular are worried about this effect because Israel is a democracy. And the Israeli Palestinians have a fertility rate several times that of Israeli Jews. Again, the average Israeli Palestinian is much poorer than the average Israeli Jew.
The Israelis are concerned because with the higher fertility rates of the Palestinian Israeli citizens, the Palestinians may become a majority in the "Jewish State" in a couple generations. This brings up all kinds of moral dilemmas for the Israeli government, who must try to balance it's commitment to a homeland for the Jews to it's commitment to democracy for all it's citizens.
A few minutes of on the Google came up with these:
http://www.economist.com/opinion/displaystory.cfm?story_id=14744915
http://www.economist.com/sciencetechnology/displaystory.cfm?story_id=14164483
http://www.cmaj.ca/cgi/content/full/177/8/846/F19
http://en.wikipedia.org/wiki/Sub-replacement_fertility
http://www.indexmundi.com/g/correlation.aspx?v1=67&v2=31&y=2004
Also, I have no idea why you brought Rush Limbaugh into this. I'm about as progressive a character as you're likely to meet. I don't know anyone that disputes this data.
Cause is another matter. Progressives would tend to contend that the reason is education, the nature of pre-industrialized societies, higher mortality rates among poor nations, the tempo of life in wealthy nations and classes.
And Rush would say they all want their welfare checks or something.
You're right about the lack of heredity for short-fatness though. It is environmental / cultural, not genetic.
Touch everywhere, even when inappropriate.