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Trial and Error: Humans as Evolutionary Mistakes
Lisa Lim
Story of Evolution/Evolution of Stories
02/16/07
Trial and Error: Or, Why Humans Are Evolutionary Mistakes
The theory of evolution is much like the process of evolution itself-in trying to reach a perfect state, it must first undergo numerous errors and changes. Biologically, evolution is the change of a population's traits from one generation to the next, a random system of trial and error in which the error, or less desirable trait, is slowly weeded out. Overtime, evolution leads to the birth of new species, each supposedly more advanced, more perfect, than the last and each capable of passing on their traits and thus, ensuring the survival of the genus. As of present day, it could be argued that evolution has found its goal in humans, who have risen as perhaps the most developed life form and who certainly have the most effect on nature, as well as on the survival of not only other species, but their own as well. However, if the goal of evolution is only to create a perfect alpha species capable of reproduction, then humans, in their current state, are certainly errors.
Evolution breeds competition, its competitive nature perhaps best summed in the term, "Survival of the Fittest." Although humans are at present day, arguably the most "fit," the alpha species, it does not make them infallible in comparison to other species. To this day, humans continue to fall victim to bacteria and viruses-they are susceptible to E.Coli, aspergillis, P. aeruginosa, the cold and flu, and a host of other bacteria and viruses, such as the retrovirus, HIV. In cases in which lethal bacteria or viruses claim the lives of human, it could only be said that, from an evolutionary standpoint, the disease had been stronger, or more "fit," than its victim and evolution had thus, further weeded out the weak. Furthermore, there are bacteria and viruses capable of reproducing and evolving so quickly that humans find it a struggle to contain or eradicate them-for instance, there is no cure for the common cold as the viruses causing the mild illness evolves so quickly. That these bacteria and viruses-often so much more simple in structure than humans-can evolve and reproduce so quickly as the evade its extinction by the hands of humans is proof that, though humans may be more complex, they are certainly not perfect. A perfect species would not be able to fall prey to another species, much less such "simple" organisms as bacteria or the virus.
In keeping with the theme of "survival of the fittest," one could argue that as eventually, all humans will die, they are certainly not perfect. Should a goal of evolution be perfection, then the simple aging that all humans undergo, while it may not be erroneous at first, eventually reaches a point in which it must be considered a flawed trait. It is certainly ideal that humans should age and grow, however, once the point of reproduction is reached or humans have reached their physical peak, one would assume that, evolutionary-wise, they would remain in such a state. However, this is not the case. Humans age and in doing so, eventually push away from a more favorable state to a lesser one. It is a backwards sort of evolution-moving from a stronger point to a weaker one until one falls victim to death. As evolution strives not only to create an alpha species, perfect for the environment, but to ensure the survival of one's species through reproduction as well, the effects of aging can play a bigger role than may be expected.
As humans age, they fall from their physical peak and lose their fertility and virility, if not completely, then to some degree. Furthermore, it becomes more risky to become pregnant as one begins to age past their peak age of fertility-pregnancy in older woman carries more risk and men are more likely to pass on less desirable traits as they get older, thus leading to offspring with more chances of genetic defects-that is, more errors. Ideally, in evolution, favorable traits are passed on in larger numbers overtime than less desirable, erroneous traits, leading to the eventual eradication of the faulty trait. In increasing the chance that one's offspring will have a (or several) less desirable trait, one thereby decreases the chance that the offspring will pass on their genes.
However, if the goal of evolution is simply to try to pass on one's genes and thus, ensure the gene's survival for at least one more generation, then this would not serve to be much of a problem. Those with genes that considered undesirable sire children all the time-it is simply that the more undesirable trait one holds, the less one is found to be attractive or an ideal mate. There are not always ways of knowing whether a person happens to hold a trait that is undesirable or not-for instance, one cannot tell simply by looking whether or not a person is predisposed to mental illness or depression, whether or not one holds the genes that makes them more susceptible to certain types of cancer or other diseases. Despite simply trying to pass on one's genes and ensure the survival of the species, however, one could still not claim humans to not be errors.
Humans reproduce at a slower pace than many other organisms. For instance, bacteria, though they lead short lives, reproduce rapidly. Humans, on the other, must first survive years to reach a fertile age. It takes an enormous amount of time and energy for parents to sire an offspring, then remain with and protect the offspring before the child reaches a childbearing age. The parents, one must remember, are already at childbearing age and the time spent caring for one offspring could be spent producing more. Yet, in producing more offspring, one only has more children to look after that require and enormous amount of time and energy-time and energy one does not gain by having children. Thus, although humans are able to reproduce, they are by no means more efficient at reproducing than all other organisms-reproduction on their part takes much longer and employs an inordinate amount of time and effort with no guarantee that their offspring will then pass on their genes. One would assume that a "perfectly" evolved creature would be able to reproduce quickly with the least amount of energy and time as possible.
Humans, despite being highly complicated and resourceful creatures, are no less evolutionary errors than bacteria. Indeed, one could even argue that bacteria are more perfect evolutionary wise than humans-able to withstand much more ranges and radicals of environments than humans and rapidly reproduce and evolve (at an astonishing rate) as to ensure the population's survival. Furthermore, whereas humans must work together in a suitable environment to ensure the population's survival, bacterial need only itself and a suitable environment-one bacterium will eventually lead to an entire colony. For all their complications and intricacies, despite all their accomplishments and drastic changes they have unleashed upon the world, humans are simply evolutionary errors who happened to get lucky.
Works Cited
"The Most Dangerous Bacteria." 01 Mar 2006. <http://www.forbes.com/2006/03/01/antibiotics-pfizer-cubist-cx_mh_0301badbugs.html>
"Increased Infertility With Age in Men and Women." 01 Jan 2004. <http://www.greenjournal.org/cgi/reprint/103/1/51.pdf>
"Reproductive Functions, Fertility and Genetic Risks of Aging Men." <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=11341301>
Comments
First of all death is a part
First of all death is a part of evolution, and is not a flaw but a form of perfection. If humans for example, didn't die, then the next generation which in theory should be better, would have to compete with the more experienced generation. Which would mean that most likely the older but less perfect generation would out compete the newer, theoretically better, generation. Death is necessary to ensure evolution continues. Also a species ultimate goal is reproduction but to reproduce that species must age to that point. Which at first may seem like a flaw, but consider the fact that without that pre-pubescent time to "try-out" those genes to see if they work at all, less desirable traits would be passed which would ultimately cripple a species not help it. Also a simple bacteria may be superior in certain ways to other forms of life, but less superior in other ways. For example you said something about needing only one individual bacteria to creat a colony of them, which makes them seem superior, sure, but that colony from one little bacteria would have almost every weakness and strength from that one bacteria, there would be no diversity. Which is a flaw in itself. Without diversity if something changes, for example the enviornment, that less diversified life form would be at a significant disadvantage because it doesn't have multiple, different, combinations of genes for that same species, which would make it less likely that the less diverse lifeform adapts and survives.
Fascinating..
I've always thought of human evolution in the same sense. I don't like to think of us [humans] as "a new test", but I don't see our race as superior nor any better than a little 10 minute old bug who was once alive and suddenly squashed. I think our human lives are full of amazement and tragedy, but I think our egos lead us to believe that we are the best and therefore must have some sort of proceeding life after we die. I believe that matter wasn't created so it can't be destroyed; Do you agree? I'd be honored to have your point of you on the topic.
Humans (and other organisms) as yet to be determined "errors"
You've done a good job of situating humans in the broad context of biological evolution (see also /exchange/node/164 and /exchange/node/175 and /exchange/node/185), of showing that humans are not the "perfect alpha species". An interesting question though that arises from your paper is should we have expected them to be, given what we know of evolution? I agree that "IF the goal of evolution is only to create a perfect alpha species", THEN we are clearly not it, and in that sense we are "evolutionary errors who got lucky". But is that in fact the "goal of evolution"? Is evolution actually well summarized by "survival of the fittest", or is there something else/additional going on that would make sense of our existence along with that of lots of other organisms, all in some sense also "errors"? Is evolution actually "trying to reach a perfect state", or is it simply "exploring" possible viable forms of existence? If the latter, then all organisms that currently exist (ourselves included) are equally "errors" and "successes" with the judgement deferred to some time in an unpredictable future.