Genetic study shows some evolutionary changes humans are currently undergoing

[Jovialis]

A team of researchers with members from the U.S., Australia and Switzerland has found that male and female humans are evolving in slightly different ways. In their paper published in Proceedings of the National Academy of Sciences, the group describes their genetic analysis of data obtained from the U.K. Biobank and what they found out about human evolution in the process.

As humans continue to evolve, questions have arisen regarding which traits might be changing, and whether they are positive or negative. In this new effort, the researchers obtained data from the U.K. Biobank (a large long-term study being conducted by researchers in the U.K. looking into genetics and environmental exposure as factors in the development of diseases).

The researchers looked only at people 45 and older in order to better understand which traits are being favored (more likely to result in producing offspring). They report that they found a few traits that stood out. One of those traits was a higher body mass index (BMI) for males. They note that because obese men typically have more difficulty reproducing, the higher BMI reading likely indicates a female preference for men with more muscle. For females, the researchers found that women who reproduced at a younger age were favored, which, they noted, was likely related to another finding—that women who reproduce early face reduced educational attainment compared to those who reproduce later or not at all.

The researchers also looked at how much the subjects weighed at birth and found that birthweight traits are so weak now that they are almost irrelevant as traits, and only appeared at all for female babies. They note this is likely due to modern medicine preventing over- or underweight babies from dying or developing problems that could prevent them from reproducing.

The researchers also note that virtually all of the traits in humans that are evolving are quite weak, which means it would take many generations to see much change. This, they further note, is likely due to both modern medicine and social change—shorter or weaker men, for example, are now able to reproduce almost as often or as easily as tall, muscular men, because such traits are not perceived by women as detrimental traits in a possible reproductive partner.

https://medicalxpress.com/news/2017-12-genetic-evolutionary-humans.html
http://www.pnas.org/content/early/2017/12/12/1707227114

I don't think there's any doubt that we as humans are currently still evolving; It's not like we would ever stop. Younger-women reproducing, with low-education attainment doesn't necessarily speak about their intelligence. Moreover, more muscular men being favored for selection, and the last segment kind of contradict one another. I guess they mean it's just obese people not being favorably selected

 

[Angela]

I don't think there's any doubt that we as humans are currently still evolving; It's not like we would ever stop. Younger-women reproducing, with low-education attainment doesn't necessarily speak about their intelligence. Moreover, more muscular men being favored for selection, and the last segment kind of contradict one another. I guess they mean it's just obese people not being favorably selected

I'm not sure about that. Low performance in academics correlates with earlier age for sexual experimentation, out of wedlock childbirth etc. I think some of that may have to do with more understanding of the consequences of having children as a teenager, and part of it may be that girls who do well in school are more likely to have plans for themselves and so are more likely to get an abortion. One of the extraordinary things about out of wedlock births in America is that they occur despite all this sex education, the availability of birth control etc. I don't get it, personally.

In terms of evolution, it's not good news. We don't need to be having preferential breeding by people with no academic abilities, poor impulse control and little sense of the consequences of their actions.

 

[Jovialis]

I'm not sure about that. Low performance in academics correlates with earlier age for sexual experimentation, out of wedlock childbirth etc. I think some of that may have to do with more understanding of the consequences of having children as a teenager, and part of it may be that girls who do well in school are more likely to have plans for themselves and so are more likely to get an abortion. One of the extraordinary things about out of wedlock births in America is that they occur despite all this sex education, the availability of birth control etc. I don't get it, personally.
In terms of evolution, it's not good news. We don't need to be having preferential breeding by people with no academic abilities, poor impulse control and little sense of the consequences of their actions.

I was considering it more as people getting married young, and perhaps pursuing academic careers afterwards. But there certainly is a lot of teenage pregnancy that is out of wedlock. So that would undoubtedly influence these conclusions as well. But just from my own anecdotal experience, I knew a lot of women that were already married with children that were pursuing a bachelor's or master's degree. One thing about these conclusions are that they don't seem to control for which populations they are talking about; and are just assessing it broadly. The study is unfortunately behind a paywall, so I cannot verify if they do control for it. What I meant to say was while it's certainly an indication, it may not be the case all of the time.

However, it would be much better if people did control their impulses, and stopped bringing children into this world if they cannot properly care for them.

 

[Angela]

I was considering it more as people getting married young, and perhaps pursuing academic careers afterwards. But there certainly is a lot of teenage pregnancy that is out of wedlock. So that would undoubtedly influence these conclusions as well. But just from my own anecdotal experience, I knew a lot of women that were already married with children that were pursuing a bachelor's or master's degree. One thing about these conclusions are that they don't seem to control for which populations they are talking about; and are just assessing it broadly. The study is unfortunately behind a paywall, so I cannot verify if they do control for it. What I meant to say was while it's certainly an indication, it may not be the case all of the time.

However, it would be much better if people did control their impulses, and stopped bringing children into this world if they cannot properly care for them.

Generally, I think the age of first marriage is getting older.

"Americans are getting married later and later. The average age of first marriage in the United States is 27 for women and 29 for men, up from 23 for women and 26 for men in 1990 and 20 and 22 (!) in 1960."

https://www.theatlantic.com/sexes/a...r-is-great-for-college-educated-women/274040/

Of course, a lot of people in minority communities don't get married at all, so that probably plays havoc with the statistics. Then, I think marital age depends on class.

Statistics have to be unpacked carefully. It's like divorce statistics, which usually say one out of two marriages ends in divorce. This is deceiving, however, because most divorces occur among people who marry and divorce multiples times.

 

[Promenade]

It doesn't sound like anything evolutionary, they're just stating what we already know. That less educated and consequentially poorer people who are more likely to marry at a young age and have unhealthy diets that lead to obesity, also reproduce more often.

Also it might be a mistake to look at just three of the wealthiest OECD countries as a standard of evolutionary trends in humanity when the majority of the world's population near the end of the century will come from the developing world in Africa and Asia, and much of the replacement rate in these western nations already comes from immigrants.

 

[Jovialis]

It doesn't sound like anything evolutionary, they're just stating what we already know. That less educated and consequentially poorer people who are more likely to marry at a young age and have unhealthy diets that lead to obesity, also reproduce more often.
Also it might be a mistake to look at just three of the wealthiest OECD countries as a standard of evolutionary trends in humanity when the majority of the world's population near the end of the century will come from the developing world in Africa and Asia, and much of the replacement rate in these western nations already comes from immigrants.

Those are good points about the developing world, and this is actually a very shallow study in my opinion. Africa is having a huge population explosion in particular, as Asia begins to slow down.

http://www.businessinsider.com/africas-population-explosion-will-change-humanity-2015-8
"More than half of global population growth between now and 2050 is expected to occur in Africa," says the United Nations report. "Of the additional 2.4 billion people projected to be added to the global population between 2015 and 2050, 1.3 billion will be added in Africa."
After 2050, Africa is projected to be the only major area that has a continually growing population, meaning that it will house 25% of the global population in 2010 and 39% in 2100.
In 1950, only 9% of the world's population was African.
Conversely, Europe is projected to have a smaller population in 2050 than in 2015.
The UN report says that several factors contribute to Africa's continued pace:
• Lots of high fertility countries. The world has 21 countries that are "high fertility," meaning than the average woman has five or more children over her lifetime. Of those, 19 are in Africa (and the other two are in Asia). The largest is Nigeria, which according to another report will have 10% of the world's births by 2050.
• Major gains in life span. Life expectancy in Africa rose by six years in the 2000s, double the global average. Africa's average life expectancy is expected to gain about 19 years by 2100,rising to age 78.
• Major declines in child mortality. In the past decade, the rate of children under age five who died went from 142 per 1,000 to 99 per 1,000. The global fall was from 71 per 1,000 in 2000-2005 to 50 per 1,000 in 2010-15.

This should be motivation for terraforming, and space colonization imo. This planet will not be able to sustain this amount of growth in population. It would require 4.1 Earths to afford an American life-style for everyone alive today. If this is going to be the projected future, then there's going to be a lot of poverty in the world.
http://www.bbc.com/news/magazine-33133712

That is, unless there is some kind of global effort done to curtail this massive explosion in population, and facilitate some kind of cultural paradigm shift in Africa, to stabilize the birthrates.