Darwinian selection continues to influence human evolution

[Tank]

Darwinian selection continues to influence human evolution

No suitable 'quote bite' so whole article copied below.

New evidence proves humans are continuing to evolve and that significant natural and sexual selection is still taking place in our species in the modern world.

Despite advancements in medicine and technology, as well as an increased prevalence of monogamy, research reveals humans are continuing to evolve just like other species.

Scientists in an international collaboration, which includes the University of Sheffield, analysed church records of about 6,000 Finnish people born between 1760-1849 to determine whether the demographic, cultural and technological changes of the agricultural revolution affected natural and sexual selection in our species.

Project leader Dr Virpi Lummaa, of the University's Department of Animal and Plant Sciences, said: "We have shown advances have not challenged the fact that our species is still evolving, just like all the other species 'in the wild'. It is a common misunderstanding that evolution took place a long time ago, and that to understand ourselves we must look back to the hunter-gatherer days of humans."

Dr Lummaa added: "We have shown significant selection has been taking place in very recent populations, and likely still occurs, so humans continue to be affected by both natural and sexual selection. Although the specific pressures, the factors making some individuals able to survive better, or have better success at finding partners and produce more kids, have changed across time and differ in different populations."

As for most animal species, the authors found that men and women are not equal concerning Darwinian selection.

Principal investigator Dr Alexandre Courtiol, of the Wissenschftskolleg zu Berlin, added: "Characteristics increasing the mating success of men are likely to evolve faster than those increasing the mating success of women. This is because mating with more partners was shown to increase reproductive success more in men than in women. Surprisingly, however, selection affected wealthy and poor people in the society to the same extent."

The experts needed detailed information on large numbers of study subjects to be able to study selection over the entire life cycle of individuals: survival to adulthood, mate access, mating success, and fertility per mate.

Genealogy is very popular in Finland and the country has some of the best available data for such research thanks to detailed church records of births, deaths, marriages and wealth status which were kept for tax purposes. Movement in the country was also very limited until the 20th century.

"Studying evolution requires large sample sizes with individual-based data covering the entire lifespan of each born person," said Dr Lummaa. "We need unbiased datasets that report the life events for everyone born. Because natural and sexual selection acts differently on different classes of individuals and across the life cycle, we needed to study selection with respect to these characteristics in order to understand how our species evolves.

Pity there isn't a link to the original work.

The question 'Are humans still evolving?' has cropped up quite a lot. It's interesting that academic research appears to show that humans are still evolving, personally I never doubted it. As the article highlights it's just the selection pressures that change.

[pytheas]

I never doubt it either.

However, I am a bit reluctant to use the term considering the ~30y  calculated lifespan and the very short temporal width of the data spanning at best no more than 400 y

With bacteria one can show that all influences have input on evolution and some man-made actions counteract, bypass, hijack or revert other more "natural" evolutionary pressures.

I tend to feel that we do "contaminate" with our conscious actions/choices and environmental manipulations and impact, our personal evolutionary trail and if anything, the data supporting more numerous offsping are out of sync with the ever increasing human population and a result of the false man-made, technology-driven promise of unlimited natural resources/space

[Tank]

I never doubt it either.

However, I am a bit reluctant to use the term considering the ~30y  calculated lifespan and the very short temporal width of the data spanning at best no more than 400 y

With bacteria one can show that all influences have input on evolution and some man-made actions counteract, bypass, hijack or revert other more "natural" evolutionary pressures.

I tend to feel that we do "contaminate" with our conscious actions/choices and environmental manipulations and impact, our personal evolutionary trail and if anything, the data supporting more numerous offsping are out of sync with the ever increasing human population and a result of the false man-made, technology-driven promise of unlimited natural resources/space

I agree with you on the generation issue. We have such a long generational period that observing a true evolutionary change in humans (ie can no longer reproduce within the gene pool) must be longer than at least 60,000 years as this is the period since the exodus from Africa. Yet there are no physical/genetic barriers preventing successful reproduction between any two fertile humans wherever they originated. 

[pytheas]

Any barrier preventing succesful reproduction is likely to influence evolution

restrictions?
-closed borders
-casts and class incompatability in culture
-famine, disease, abject poverty
-contraceptives

human emotional-logic behaviour has evolved to be supra-evolutionary

[Ecurb Noselrub]

Here's an article on relatively recent brain evolution in humans.

http://www.livescience.com/7971-humans-evolving-brains-shrink.html

And about rapid evolution among Tibetans:

http://www.nytimes.com/2010/07/02/science/02tibet.html

[Squid]

Pity there isn't a link to the original work.

Ask and ye shall receive 

http://www.pnas.org/content/early/2012/04/24/1118174109

If anyone wants to read the full paper, let me know.