Natural selection among humans.

amirbey's picture

It was on a Saturday night that my friend Sarah and I had decided to order out.  Usually, we eat in front of a TV show, but this time, the internet was not working, so we did the only thing two young women can do when they are alone; we conversed.  Since I had gone to some classes on the Story of Evolution and the Evolution of Stories, I surprised myself asking Sarah quite a few essential questions that had been on my mind, such as, is there a God out there?, are we not alone in the universe?, what is a good definition of life?, is it immoral to abort?, and finally, it led me to ask myself about the human’s natural selection.  Is it still being applied?  Haven’t we modified or even destroyed the way natural selection acts upon us?  

I believe natural selection is a problem when it comes to humans.  However, it does not seem to cause any trouble for the other living organisms on earth.  Indeed, if an antelope has a defect that affects its ability to run at birth, natural selection will act upon it.  The antelope will be killed by a predator, since it runs slower than the others of its kind.  Therefore, most of the antelopes run fast and the lagging ones are the ones to be eradicated from Earth.  Now, if we take the example of human beings, we do not have any natural predators, so how can natural selection play out on us?

If we think about the ancestors of the human descendants, such as the Homo neanderthalensis, the Homo erectus, and so on, they were starting to evolve towards a human being but they were still very close to the apes.  According to modern humans, our ancestors were closer to animals, such as these, than humans, and therefore, natural selection was acting on them quite easily.  According to Charles Darwin, natural selection acts only for the good of each organism, so since our very first human ancestors had no natural defenses, they would die from what is considered today an insignificant disease.  It was throughout millions of years, that the human body started to build an immunization to certain diseases and only the stronger humans were the ones to survive and carry on that trait. Likewise, having no fur on their bodies to survive in the cold weather, they learned how to use other animals’ skins and how to build some weapons, in order to chase wild animals. 

Nowadays, humans have made incredible discoveries; we have created a wonderful world of technology, which leads us to make some enormous progress in the field of medicine; especially in how to treat diseases which were, at some time, considered incurable.  My point is, that since we have made such progress in technology, I am scared that we are keeping too many people alive, including some that might not fit the environment in which they live.  In addition, we are allowing some infertile people to reproduce through in-vitro fertilization, when apparently they were not capable naturally.  We are also letting babies survive by saving their lives at their birth even though they might not be perfectly healthy or other traits which could be detrimental for the human species.  But through science and the new technology, we have let these babies live and we have given them the opportunity to grow up and reproduce, transmitting their traits to other generations.  Due to these facts, it is very probable that we are acting against natural selection in human beings, ever since humans became people who think and care for one another and we have made it immoral to kill another individual or to let him die.  

However, we could think about another definition of natural selection, such as a life on Earth dies if it is not adapted to its environment and it lives if it has a niche and can reproduce in its surroundings, which is also called survival of the fittest.  If we take the example of a fetus in his mother’s womb, the body of the mother can detect some errors coming from the fetus, and it would eliminate the fetus through a miscarriage.  So, in this case, natural selection does still act upon human; acting within the womb of a woman, and therefore, not let a human being, which would not fit its environment, survive.  For instance, we have not seen any people carrying the traits of Down’s syndrome on the chromosome 14.  It is likely that this defect happened before but only inside a woman’s body which eliminated the mistake through a miscarriage, not letting the future human see the light.  So, in this case, the fact that humans are living longer, letting them reproduce thanks to many discoveries such as in vitro fertilization, surgeries, transplants, medication, etc., is because we are taking into consideration that the technology is part of our environment.

So what can we say about the natural selection of human beings?  This is a question that is important to me but to which I unfortunately have few answers.  Is it a good thing to let people live longer?  Should we try to protect our species by destroying our technology?  Should we stop trying to help ourselves and let natural selection do its job?  I believe the right question to ask ourselves would be: is technology considered a part of our environment, or are we really deviating the normal course of evolution? If we were talking about human beings as a species we should let natural selection work on its own, however, we have become more than a simple species.  Indeed, we are superior to any other life on this planet because we have acquired the ability to think and care, not just simply Homo sapiens.  I think we might have modified, by becoming people, the instinctive course of natural selection, but I am still awaiting proof either way.   

Comments

guest's picture

natural selection

I found the car accident discussion fairly interesting in relation to the natural selective process. Surely slow reflexes, impaired movement of limbs, etc would play a role in natural selection acting upon you, and ultimately, your downfall (death). In addition to these physical traits or mis-traits that dictate whether you survive or not, I think that in modern society, the natural selective process has evolved as well; that is, to "catch up" with the times and find new ways to differentiate the superior genes to the lesser ones. If natural selection was an entity of some sort, it would see humans surviving well past traditional means of "being too slow therefore you get eaten by a tiger" type situations. Take into consideration: Cancer, STI's, other contractual diseases and the like, a lot of these are aftermath afflictions due to decisions made by lesser humans (purely for theoretical sake, not to offend anyone). Unprotected sex, eating processed foods, wearing makeup, standing in front of a microwave etc, natural selection could now very well be basing its victims on whether or not you have the mental capacity to not partake in these activities. Worse yet comes variables we personally can't control yet will still lead to our downfall (respiratory illness etc) such as air pollution made by humans, these cumulative actions take effect on society as a whole, as in the majority of people don't care therefore we all suffer. Perhaps this rat race has gone too far, and nature will bring the hammer.

Tyler of Algoma's picture

Technology and Spencer Confusion

I like that you combine philosophical questioning wwith biological theory, however how you've labled 'natural selection' as what seems to be, by my understanding, Spencer's 'survival of the fittest,' a theory which is by all means something separate.
Humans are born with their reactive traits and the basic rubrics for their personalities imprinted int heir DNA; their environment (ie. the technology around them, the events they experience, etc) alter that DNA in miniscule amounts that allow us to be more adaptive to our surroundings. We develop schedules beyond daylight hours, we build ourselves up structurally and often egotistically in terms of what is necessary to progress in a highly complicated society; that we are capable of identifying with this society with general ease is proof of this. However, those who exist to procreate the most are generally not the 'fittest' for this model, those who are either physically or mentally superior. Sadly it is the idiot fringe that reproduces the most, elsewise the world of humanity would be utopian.
The example of natural selection in your article, of a mother miscarrying a defective offspring, is closer to survival of the fittest. Natural selection means doing all you can to adapt and pass on such adaptions in a way that will produce as many progeny as possible. A down-syndrome baby would register as a liability to that goal, true, however why is it that intellectual beings are not disposed of in the same way. Obviously it is the lower end of the intelligence scale that reproduces the most, so what purpose would there be in creating more smart babies? None, is the answer, at least in a world where organisms are allowed to adapt to artificial technology.
I know, the idea of comparing fetuses with down-syndrome and fetuses with a large capacity for knowledge is fairly extreme, however in the rest of nature, only basic instincts are required to progress as a species, not intelligence nor cunning nor any specific trait, not even aggressiveness or speed.
What I am trying to say from all of this is that the advancement of human technology is an example of spencer's SotF, not Darwin's NS. Miscarriages based on defects in the fetus are also in Spencer's territory, as there is no adaption involved in this scenario, nor does it further procreation. An example of Natural selection in humans would be how some people are being born without wisdom teeth: many people have them removed before they reproduce and as our jaws are noticeably smaller than in centuries past due to diet adaptations, they have no need to have any.
I agree that it is going against Natural selection by keeping those who would otherwise die off, however developing new ways to maintain long lifespans is how we academics have adapted to survival - we wouldn't last a week out on the savanah of 1 million years ago, while the brutes, runners, and fat storers would have no problems at all. Yeah, it's harsh, but the real world is not the sugar coated paradise many would like to believe.

Anonymous's picture

The Arrogance

We valorize the natural because man can never come even close to its perfection.

I suggest Anne Dalke to read a bit more about nature, and a bit less about our marvelous deeds which seem to be actually pretty destructive overall.

And we didn't invent DNA. We discovered it. And no, I'm not particularly inclined to think about technology the way her student does. She's still got a lot to learn. So does her teacher, apparently...

Serendip Visitor's picture

worthless debate

Oh, boohoo another stick-in-the-mud naturist...

Have you even considered the subject matter here? Nature in all her infinite wisdom I'm sure has created us the way we are, unless you believe in a higher power or devine intervention (and as a scientist you should at least be a little sceptical about your own beliefs).

Therefore, the consensus is that man has already achieve natures perfection by being part of it. It's not exactly a members-only club, Sherlock, any living thing on this entire planet is a continuation of natures grand design. All our technological advances would not be possible without nature, survival and evolution so by definition nature is responsible for our destructive ways. Nature shows destructive traits in all living things from dangerous pathogens and parasites to tree canopies, these are natural devices designed to kill or deplete another being for the survival of the primary being. Left unchecked these processes, much like our want and need for technology can become a global destructive force.

If evolution/natural selection is anything to go by then our time on this planet only serves to provide a stronger subset of species.

Please do some reading or better yet some 'understanding' of your own before you go around posting insulting and demeaning responses to what is a well written article.

chase's picture

it is

I too have found this to be a very hard subject to grasp. If natural selection is changing with technology then would you be able to go as far as saying car crashes, cancer, STD's are now a part of the human natural selection procses. is a car crash made possible by a slick road from rainfall is that a part of mother natures natural selections process? Or does natural selection rely on survival of the fittest? Is a death only natural selection when the better of two humans or animals is the victor of fate.

Serendip Visitor's picture

Even fate might play a very small part.

Looking at the subject with a very simplistic view, I would say that fate obviously has very little affect on natural selection, however, think of it this way in terms of the car crash, if the driver has slow reflexes, poor eyesight, bad judgement etc. then is de-selected in a car crash he will be unable to pass these genetic traits on, I realise this might sound quite extreme and there are obviously bigger factors than this that influence natural selection, but it seems that mother nature plays the odds, much like a casino, she's in it for the long game, every small gain in the genetic pool is compounded over thousands of years.

As for cancer, although environment plays a very large factor, I believe there is also a genetic pre-disposition. Why else would medical forms have the questions on family history, but cancer is also a tricky one as it is considered (although not exclusively) a disease of old age and a lot of victims will have already reproduced and possibly passed on genes that have a predisposition for certain types of cancer. Tragically this seems like another one of mother natures long games.

STD's diseases seem to have there own natural selection process, .ie. drug resistance, a body might contain a billion of a certain strain of bacteria that is constantly reproducing, occasionally when the bacteria reproduce there will be a genetic mutation that is passed on to (for want of a better phrase) the offspring of that bacteria, by pure chance, one of these mutations might help in the resistance to a certain antibiotic, so when the antibiotic is administered, this bacteria and/or its offspring are not effected, all the other bacteria are eliminated, and the only ones that remain and are able to reproduce are the ones with this genetic mutation and therefore the body is repopulated with drug resistant bacteria. Conversely it may be possible for a human to be born with a genetic mutation that is resistant to the bacteria and would then have more chance of staying alive to pass these genes on. However, as the average reproduction cycle of a human is about 25 years, and the average reproduction cycle of bacteria is probably 25 seconds then I think it unlikely that we are ever going to beat bacteria naturally.

Please don't use any of these ideas as part of educational coursework without checking them out, as these are just my ideas that I think about (as I do a lot of motorway driving everyday).

Anne Dalke's picture

valorizing the natural?

Why do you valorize the “natural”? What makes that process “superior” to one that is more artful, technological, human-crafted? As a step toward answering that question, you might want to look @ epeck01’s paper on “Mankind’s Influence on Evolution”, crrichar’s piece on “The Evolution of Species in Relation to Technology in 21st Century” and Sophiaolender’s “How We Made the World What We Wanted it to Be”--in order to compare the different spots where you all come out on these questions.


What you call “the right question to ask ourselves”--“is technology part of our environment?”—put me in mind of some insights that have emerging in another course I’m teaching this semester, on Gender and Technology. There (of course), our main question has to do with how we understand the relationship between the two terms in our class title. Last week one of the students flagged a comment from a website we’d looked @ for class, which talked about DNA as a “technology” itself that inscribes itself on us; she later wrote a longer paper, called Trans() to explore this idea further. What happens to the questions in your paper, if you begin to think about technology in the way she does: not as something “other” or “separate’ from ourselves, but as something that both “made” us (the DNA code that tells us how to be human in the first place) and as something we have made, and are continuing to re-make? What then become the “right questions to ask ourselves”?

Serendip Visitor's picture

Yes, valorizing the natural.

What makes natural processes superior to any human pretensions to surpass it?

Natural processes do not pollute the earth on a global scale, and do not cause avoidable mass extinction of other species. Equilibrium, not overpopulation and greed. Better adaptation, not destruction and survival of the worthless. In brief, infinitely superior.

The only error of nature was to have spawn a parasitic, arrogant, destructive super-organism that considers itself the "crown of creation" and has been driving all other species and its own habitat into non-existence.

And of course, who is still bragging about its own "artful, technological, human-crated" thingies...

Bones's picture

Finally

My exact thoughts for years!

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