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Mankind's Influence on Evolution

epeck01's picture

In Darwin’s On The Origin of The Species by Means of Natural Selection, the basis for modern evolutionary thought is explained.  Darwin starts his text by explaining how he was drawn to the evolutionary field and what observations helped him come to his conclusions.  The main prompt Darwin found was in breeding.  He observed that breeders “selected” for certain traits in animals and were able to alter the characteristics of species and even create new species through selective breeding.  Recognizing the effects of selective breeding, Darwin applied the concept, using other observations as well, to nature.  Out of this application came the theory of natural selection and survival of the fittest.  When looking at Darwin’s theories today, the most striking modern application is the moral and biological dilemma we face in this age of technological and medical advances in regards to evolution.  We can now alter our genes, make those who are infertile conceive, heal those who would have otherwise died, and provide so many other medical ways to meddle with our species’ evolution. With so many ways to manipulate survival of the fittest, are we impeding our own evolution?

Chapter One of The Origin of The Species is titled, “Variation Under Domestication” because it deals with the variations present in domesticated animals, specifically pigeons.  Darwin was a pigeon-fancier and therefore was able to closely observe the species and their modifications under domestication.  Using his observations on domesticated pigeons. Darwin makes the claim that according to his findings, and the beliefs of many other fanciers, species came from a certain limited stock of animal, and then branched off into separate species, often outnumbering the number of original separate species.  Although this is interesting in itself and makes a claim that was not largely thought of in Darwin’s time, the aspect of the chapter I find fascinating is the capability humans have, and have had for a long period of time, to domesticate and modify other species.  The idea is slightly disturbing, because although man-made modifications may be slight in the grand scheme of things, we are in some ways playing g-d, or whatever force Darwin believed to be leading evolution.  If we are able to play the creator’s role in the evolution of other species, what is to stop us from maneuvering our own track of evolution, and perhaps irreversibly changing what we should not have interfered with at all.

Medical advances over the years have allowed mankind to take a role that in other creatures are left up to random chance and natural variation.  As soon as mankind discovered how to treat diseases, those with the disease who would otherwise have died and therefore not continued their genetic lines were given the opportunity to reproduce and continue their faulty lines of heredity.  Although Darwin did not understand the genetic aspect to evolution, the genetics that were discovered later fit almost perfectly into most of his theories.   Some ways of genetically manipulating our evolution could prove to be harmless, such as selecting eye color or sex in test-tube babies.  Although this would modify the gene pool and therefore not truly be natural selection, the overall fitness of mankind would probably not be compromised.  

However, some forms of manipulation could be potentially harmful to mankind’s fitness and survival.  Allowing those who would have died without medical support to live could be hampering mankind’s natural evolution.  Another way that people play with the “intended” course of evolution is allowing those who are not able to have children to conceive.  There must be a medical and evolutionary reason that infertile couples are infertile.   By allowing them to have children we are not evolving towards a perfect state as Darwin suggested.  Instead, we could be evolving, or rather stagnating, into a sickly species, one that is unable to fend for itself, or even propagate without medical assistance.  

The cringe that is normally associated with a statement such as the above, to me exemplifies the fact that we are not in fact impairing our own evolution.  Darwin did not cover psychology in his text, however he did discuss instincts, and though that they must have evolutionary bases along with every other characteristic of a species.  For some reason, according to Darwin a random selection, humans have evolved to have feelings of guilt when proposed with the idea that we should not help those whom we have the ability to.  This adaption must have come to be in order to serve a purpose in evolution.  We may have adapted to the extent that we are now able to adapt our own paths and therefore our own evolution.  Although this idea may seem somewhat religious and therefore ill fitting in Darwin’s theory, especially considering his idea of the random course of evolution, I believe that we are not impairing mankind’s evolution.  I believe rather that what is must be meant to be simply because it is.  According to Darwin, evolution leads to perfect species and is random.  Therefore, the progress we have made so far must be a step along this path.  Although some would say that we are now toying too much with our own evolution, the progress we have made must simply be a means to the perfect species that Darwin predicts.


Anne Dalke's picture


You spend most of your paper tracing the argument against human meddling in “natural selection,” before staking a clear claim, in conclusion, that “we are not in fact impairing our own evolution” by such manipulation. (You might want to look @ amirbey’s paper on "Natural Selection Among Humans"; 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”--to compare the different spots where you all come out on these questions.)

Your final turn was a surprise to me, and even more surprising was the logic you used to argue that position. Three times in your finale paragraph you evoke the “perfect state” and “perfect species” that Darwin suggested we are moving towards, as the ground for saying that what is must be meant to be. Paul’s lectures have suggested that biological evolution is not—cannot--be moving toward perfection and that Darwin was conflicted on this question, probably too much of an empiricist to have wrestled seriously with the question of teleology. Maybe that’s why I’m not quite following-and so want to push back a bit on--your argument here. I don’t see why “what is” couldn’t as easily be explained, following Darwin, as the result of undirected, non-teleological randomness. Why must the steps we’ve taken be fated, inevitable?

mimi's picture

God created things to be as

God created things to be as they are and not altered. Although, I feel that some technical progress is helpful to human survival, I feel that cloning and things of that sort are just ridiculous ways of spending and making money.