Evolution continues despite low mortality and fertility rates in the modern world

Charles Darwin's theory on evolution still holds true despite lower mortality and fertility rates in the modern world, according to new research by the University of Sheffield.

Scientists looked at how cultural influences like easy access to contraception and medical advances reducing infant mortality, effects natural selection in populations.

The study, carried out in Finland, observed that while only 67 per cent of children born in the 1860s survived to adulthood the figure rose to 94 per cent during the 1940s. At the same time, people went from having an average of five children to 1.6 children during their lifetime.

But despite artificial influences the study found between humans are what continue to fuel evolution.

Dr Virpi Lummaa, from the Department of Animal and Plant Sciences at the University of Sheffield, and Dr Elisabeth Bolund, now at the Uppsala University in Sweden, used genealogical records collected from Finnish churches starting at the beginning of the 18th century and still being collected today. By assembling family trees over several generations of over 10,000 individuals, they could sort out how much of the variation in a trait is due to genetic influences and how much is due to environmental influences, and how the determinants of key traits for evolutionary success may have changed over the modernisation of society.

The study found that in the 18th and 19th centuries, about four to 18 per cent of the variation between individuals in lifespan, and ages at first and last birth was influenced by genes, while the rest of the variation was driven by differences in various aspects of their environment.

"This is exciting because if genes affected differences between individuals in these traits, it means they could also change in response to natural selection," said Dr Bolund. "But we know that the environment has changed rapidly and dramatically, so we investigated the genetic basis of such complex traits and their ability to continue changing through evolution."

The study showed that the genetic influence on timing of reproduction and family size tended to actually be higher in recent times. This means that modern human societies can still respond to selection, and genetic differences between us continue to fuel evolution.

"It is possible that we in modern societies have more individual freedom to express our genetic predispositions because social and normative influences are more relaxed, and this leads to the genetic differences among us explaining more of the reproductive patterns," said Dr Bolund.

Complex traits like the ones in the study are each influenced by many different genes, while at the same time, several different traits can be affected by the same genes. The authors found that the that is shared between the studied reproductive traits and longevity did not change over time.

"This is reassuring if we want to use current patterns of and to make predictions of what will happen in modern human populations over the next few generations," added Dr Bolund.

"Our results can help us when we want to predict population responses in the face of global challenges such as prevailing epidemics, ageing populations and decreasing fertility."

The paper is being published online by the journal Evolution on Thursday 5 February 2015.


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Feb 05, 2015
"This is exciting because if genes affected differences between individuals in these traits, it means they could also change in response to natural selection,"


Umm, what Natural Selection? Humans have no persistent threats, therefore no natural selection occurs. The only natural selection would be if a human is born so unhealthy that it cannot live and reproduce. There is no natural selection because every human can reproduce easily, and there is virtually no evolutionary trait that would increase its ability to reproduce over another human. Maybe if you took extreme risks and die too young to reproduce, or if you were really ugly you might not reproduce, but that is about it. Evolution through natural selection does not work for humans.

Feb 05, 2015
A 200 year time span is insufficient to measure evolutuonary changes in human beings.

Feb 05, 2015
"This is exciting because if genes affected differences between individuals in these traits, it means they could also change in response to natural selection,"


Umm, what Natural Selection? Humans have no persistent threats, therefore no natural selection occurs. The only natural selection would be if a human is born so unhealthy that it cannot live and reproduce. There is no natural selection because every human can reproduce easily, and there is virtually no evolutionary trait that would increase its ability to reproduce over another human. Maybe if you took extreme risks and die too young to reproduce, or if you were really ugly you might not reproduce, but that is about it. Evolution through natural selection does not work for humans.


Its not just about reaching reproductive age, its also about how many offspring you produce. Certainly there is a lot of variation out there!

Feb 05, 2015
You are right, I have thought about it some more, and diseases/viruses/epidemics are one form of natural selection that acts on humans. The number of offspring you produce does further your genes, so, that may be the most significant driving force for evolution of humans. You are also correct about "which humans are we talking about", because there are huge differences in different places.

The real question I would like to answer is: Where does evolution have to go with humans? What improvement could be sought? We already have so many adaptations and abilities, like evolution just went nuts on us already. How can we adapt to our environment when we spend so much time and energy adapting our environment to suit us? It seems to short-circuit evolution itself.

But there is more to evolution than that. Genetic Memory gets passed down, and each offspring likely will be just as good or better at a given task than their parents are. You think someone from the 1800's could handle a PC?

Z99
Feb 05, 2015
It is wild speculation to claim that intelligence is (generally) a beneficial trait. Sagan's old book Dragons of Eden comes to mind. I'm not claiming it still holds up to scrutiny, but the idea that the modern mind may be only 60 or 100,000 years old implies that intelligence is an on-going experiment. Based on our use of resources (not sustainably), our pollution (pollution load of planet is increasing), anthropgenic climate change policies, and causing a mass extinction event, I wouldn't give you even money that the experiment will show that there is intelligent life on Earth.

Feb 05, 2015
@Z99

Intelligence does not necessarily equate wisdom.

Feb 05, 2015
@Z99

Intelligence does not necessarily equate wisdom.


I work at a software startup and the lack of wisdom is astounding. It boggles my mind that so many bright people can be so collectively unwise.

Feb 05, 2015
Creationists are dying out.

JVK
Feb 06, 2015
...in evolutionary terms, that means a strong selection for genes that favors people who like having children.


Children are quantum entanglement devices that facilitate links between the epigenetic landscape and the physical landscape of DNA. Sex differences in cell types at the advent of sexual reproduction in yeasts are linked to brain development in humans via the biophysically constrained chemistry of protein folding and RNA-mediated amino acid substitutions that are fixed by the pheromone-controlled physiology of reproduction in species from microbes to man.

Lack of brain development is attributed to beliefs in theoretical physics or in evolutionary theories about molecules evolving in deep space and people evolving from other primates. That's the kind of pseudoscientific nonsense that prevents scientific progress.

See for comparison: http://www.ncbi.n...23206328
"A quantum theory for the irreplaceable role of docosahexaenoic acid..."

Feb 06, 2015
Children are quantum entanglement devices . . . biophysically constrained chemistry of protein folding and RNA-mediated amino acid substitutions . . . pheromone-controlled . . .

Lack of brain development is attributed to beliefs in theoretical physics or in evolutionary theories about molecules evolving in deep space and people evolving from other primates. That's the kind of pseudoscientific nonsense that prevents scientific progress.

Publish an article that mentions evolution. It's like poking a bear with a stick. Looks like he's lashing out at everyone now. In one sense, I wish he'd go away and leave us alone. On the other hand, watching him devolve into incoherency is weirdly entertaining.

Feb 06, 2015
Humans have no persistent threats, therefore no natural selection occurs.

You don't need any threats. Any mechanism that favors genetic trait X over trait Y when it comes to reproduction is enough. This can be something as simple as (fictitious example) "people considered short people ugly in the 1800's". Consequently you'd get the shorter people selected against while the taller people get selected for.

Feb 06, 2015
Umm, what Natural Selection? Humans have no persistent threats, therefore no natural selection occurs.


This may be partially true in the developed countries but not in the rest of the 3/4 of the planet. And even here there are treats like diseases, pollution or local or global climate changes. We may even see cultural influences.

Of course mutation and/or diversity is not per-se evolution and we could only be able to confirm that in a far away future, but natural selection does exist.

Another question may be if we have changed the rate of evolution or temporarily stagnated it , but evolution is just as his mother entropy, it never stops.

Feb 06, 2015
Therefore, in evolutionary terms, that means a strong selection for genes that favors people who like having children


That is key to this conversation, because almost anyone can reproduce, the ones that do it more than others are passing down their genes more. But the thing is, there is no selection, as most offspring survive.

What is true is that medical care is allowing weaker and weaker people (with presumably weaker genes) to thrive. Example - I have asthma, and my wife has asthma. We were hospitalized with it a few times while growing up. In the old days, before modern medicine, we would/could have died. But modern medicine prevented that, now we have a daughter and she has asthma too.

The more we treat and work around our problems (when it comes to health/genetic defects) the more of them we will have, weakening the gene pool.

JVK
Feb 06, 2015
Publish an article that mentions God. It's like poking a science idiot with a stick. Unless you are Stuart Kauffman

http://blogs.scie...steries/

Excerpt:
Horgan: What do you make of the antipathy toward religion expressed by Richard Dawkins and other "New Atheists?"

Kauffman: It is wonderful for them to have expressed the truth that moral behavior requires no belief in God. Morality probably evolved in Paleolithic to some extent. But to dismiss those who do believe in God, in any sense, is arrogant and useless and divisive.

My comment: Those who believe in God are less likely to believe in the pseudoscientific nonsense about mutations, lactose persistence, and evolution. They are more likely to look for explanations of how physics, chemistry, and molecular biology collectively contribute to RNA-directed DNA methylation and RNA-mediated amino acid substitutions.

Feb 06, 2015
But your neighbor had 4 child at 15 years old. He will have 16 nieces at 30 years old, 64 grandnieces at 45 years, 256 on his 60 birthday, 1024 at 75, and 4096 descendants at 90 years old.


I think the word is Grandchild, not "Niece". A niece is the female offspring of your sibling. And lets hope there is enough welfare to go around for the 4096 children born of 15 year old mothers!

Feb 06, 2015
Publish an article that mentions evolution. It's like poking a bear with a stick. Looks like he's lashing out at everyone now. In one sense, I wish he'd go away and leave us alone. On the other hand, watching him devolve into incoherency is weirdly entertaining.
Ha, good post!

JVK
Feb 06, 2015
Ha, good post!


Posts by science idiots are considered good by other science idiots.

For comparison, see: Prolegomenon to patterns in evolution http://www.scienc...14000380

Science idiots refuse to address "anti-entropic" processes, which is why I provided this link:

http://blogs.scie...steries/

We need accelerating expansion of universe for free energy and "tuned constants" but those are necessary, not sufficient. The anti-entropic process may be, with others, sufficient. I am writing a new book about this.


By the time science idiots figure out what the anti-entropic process is, many more people will have either suffered or died from evolutionary theories about mutations that cause physiopathology that pseudoscientists think leads to natural selection and/or evolution.

Feb 06, 2015
Therefore, in evolutionary terms, that means a strong selection for genes that favors people who like having children

Not necessarily. If food/water is limited then having more children is worse than having fewer. If there's barely enough food to feed three then a family with 10 may completely starve to death before making the hard choice whereas a family with only one child might survive.
More children (in a small space) means also potentially more exposure to transmissible diseases.
In wealthier countries less children means you can expend more resources (e.g. money for medicine/education) on your kids - which may mean that more survive to breeding age than from a family with many children.
Also kids with assets are a bigger draw for the opposite sex, so there's a mating advantage as wealthier kids can choose among a larger pool (potentially selecting a partner with healthier genes to mate with).

So there are forces balancing the 'maxium offspring' strategy.

Feb 07, 2015
Low morality in modern society that with each successive generation further decline is due to darwin's theory of evolution, which also failed to explain how living organisms evolve and what is needed to be posible such a process. But managed to destroy Christian values in society by deceiving young citizens of the society in school with pseudo science in the period when building their worldview, thanks to which Europe and America experienced its time of socio-economic, cultural and scientific progress. Unfortunately this is past and regresiyata already goes irresistibly not unaided.

Feb 07, 2015
How high was your sperm's I.Q.?

motivational speech: "Every human has been number one at least one time in their life! You have potential!"

Do humans "remember" being a sperm and an egg?

You need 4 kids with each partner in order to have above a 90% rate of your genes being passed on, but because you don't know if the partner has negative genes that you don't know about, it might be beneficial to mate with other partners as well, preferably unrelated to one another as possible in order to maximize genetic diversity.

Might want 4 kids per mate, and like 5 or 6 mates:
Asian
European-white
European-latin
African
Arabian
Native American

Now you will have a much higher chance of your genes being passed on, because you will have offspring among each major racial group if one of hte mothers has bad genes, the others probably don't.

Feb 07, 2015
Umm, what Natural Selection? Humans have no persistent threats, therefore no natural selection occurs.


Natural selection will favor anything that results a greater number of healthy children. For instance, a strong sexual desire in teenage years, earlier puberty, greater vanity that results in someone sending naked selfies or dressing to increase sexual interest, a lack of sensitivity with condom use that results in less condom use, etc.

Think of our genes as being at war with us for our reproductive abilities: whatever actions we take to limit reproduction (delayed relationships, contraception, etc.), genes will look for ways to work around those attempts. If you personal end up staying in control by reproducing "responsibly" or not at all, you still lose because by being responsible your "responsible reproduction" genes are automatically selected out of the gene pool.

As long as there are variation in genes which effect reproduction, evolution is unstoppable.

Feb 07, 2015
Any gen that creates a tendency to have more children will be selected.

Not necessarily. The number of children is not the figure of merit. The spread of the genes is. A 'rich' culture with few children where the children are mobile will outevolve a fertile group that is not mobile (i.e. where the many children still stay within their pool).

The 2-4-8-16...row only works if there are no inbreeding lines. With a population that is mobile such inbreeding is almost guaranteed.

Feb 08, 2015
The 2-4-8-16...row only works if there are no inbreeding lines. With a population that is mobile such inbreeding is almost guaranteed.


I think genetic diseases may be the result of generations of too much in-breeding. Marrying your third cousin might not be a big deal, but 10 or 20 generations of people marrying third and 4th cousins (or genetic equivalents) becomes a problem.

Why do even small populations of monkeys have more genetic diversity than humans?

Where is our blue hair if we are descended from apes, because they have blue markings.

I like 19yrs olds, and 26 yrs old, and 30, and 35, and 45, heck the other day I found myself attracted to a 51 yrs old woman and it didn't even feel weird.

Mambo #5. I guess the guy had it right you know.

JVK
Feb 08, 2015
http://phys.org/n...firstCmt
22 hours ago "Returners" wrote:

Classic "Evolution" is the hypothesis that all-new genes spontaneously appear on their own as adaptations to new environments.


No response to my requests for clarification has been posted, yet here we have even more nonsense added to other discussions by someone who appears to have no knowledge of physics, chemistry, or molecular biology but who continues to tell others about evolution.

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