Thursday, February 12, 2015

Historical Influences On Darwin: Thomas Robert Malthus

1. Many individuals' works and studies prior to Charles Darwin affected his development of the theory of Natural Selection in both positive and negative ways. Out of many works and studies, Essay on the Principle of Evolution by Thomas Malthus has become a cornerstone for Darwin's theory of Natural Selection. Because Darwin had interests in Economics, he noticed Thomas Malthus' work, which said that overpopulation is a real problem that will lead to a famine and destroy the country. From reading about this idea, it occurred to Darwin that animals and plants should also be experiencing the same problem of overpopulation. This curiosity resulted in Darwin starting his studies and developing a theory.

2. Thomas Robert Malthus is most known as a person who provided the starting idea of "survival of the fittest" to Darwin. The central argument of the Essay on the Principle of Evolution lies in two postulates: "That food is necessary to the existence of men," and "that the passion between the sexes is necessary, and will remain nearly in present state." The scientific community can draw two major conclusions from his work. First, the power for species to reproduce is infinitely stronger than the ability for Earth to provide enough resources for men. Second, population, when left alone, increases in geometrical ratio while the number of available resources grow arithmetically. This means that even the slightest difference could result in immense unbalance of numbers. However, with these two conclusions, scientists and researchers need to keep in mind that Malthus made these points by taking his postulates as self-evident, ignoring the possible events or factors that would disrupt the growth ratios of both the population and the resources.
Website: http://www.encyclopedia.com/topic/Thomas_Robert_Malthus.aspx

3. All organisms have the potential of reproducing exponentially.
   -This part of the idea came directly from Thomas Malthus' Essay on the Principle of Evolution. In his work, Malthus explains that population grows in geometrical ratio if left alone with enough resources. 
   What is preventing organisms from reproducing at their potential?
   -Malthus explains that population grows immensely faster than the reproduction of available resources if population is left unchecked. The factors that would prevent organisms from reproducing at their full potential would be instances where the population has to fight for resources, when there is an epidemic, natural disaster, or famine.
    Resources are limited.
   -Because resources grow in arithmetic ratios, it will eventually be caught by exponentially growing population. There are simply not enough resources for every species to reproduce indefinitely on Earth.

4. Charles Darwin's theory of Natural Selection might have not been so developed and well studied without the idea of Thomas Malthus. Thomas Malthus' idea became the cornerstone for Darwin's theory, allowing Darwin to save time thinking about a fresh new idea. Darwin's saved time allowed him to observe more critically and provide with a well tested and thought out theory of Natural Selection. 

5. During Charles Darwin's times, the atmosphere between the Church and the scientists were very tense. This atmosphere was the result of the Enlightenment, an era characterized by dramatic revolutions in science, philosophy, society, and politics. The Church fought against any idea that seemed to conflict with their beliefs and tried to prevent the conflicting ideas from spreading across the world. Their efforts delayed the eventual publication of Darwin's works. In current days, evolution is a widely accepted idea, and while the Church accepts some parts of evolution, it still holds on to their belief of Creationism. 

2 comments:

  1. I struggled with the choice between Malthus and Lyell as to who I felt was a larger influence on Darwin. Your post makes me almost rethink my choice of Lyell! Almost. It also makes me think of the first chapter in On the Origin of Species where Darwin details his findings on what happens when animals are domesticated and bred in captivity. He says there that "Many facts clearly show how eminently susceptible the reproductive system is to very slight changes in the surrounding conditions. Nothing is more easy than to tame an animal, and few things more difficult than to get it to breed freely under confinement, even when the male and female unite." I have no doubt that Malthus' influence was very strong.

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  2. Quick correction: Malthus wrote a book called "Essay on the Principle of Population", NOT of "Evolution".

    Good description of Malthus' work. Clear explanations.

    By the way, Darwin was not the one to come up with the term 'survival of the fittest" and it isn't actually a good description of his theory. It was created by Herbert Spencer, an anthropologist, after reading Darwin's work. Darwin incorporated it into his 5th edition of Origin of a Species, but biologists actually avoid it like the plague. I even cringe every time I read it in these posts. ;-)

    Excellent choice of your three bullet points. Those are the same three I suggest are best applied to Malthus.

    Not sure if the importance of Malthus' work is that he "saved time' for Darwin. Darwin was actually quite stuck on his theory until reading Malthus' book. Darwin even seems to suggest this in his notes:

    "... it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The results of this would be the formation of a new species. Here, then I had at last got a theory by which to work".

    Charles Darwin, from his autobiography. (1876) http://www.ucmp.berkeley.edu/history/malthus.html

    I appreciate your description of the relationship between science and the church during Darwin's time but recognize that, in Darwin's case, they didn't even know about his work until after he published, so there was no direct pressure to delay publishing. This was all Darwin's decision, but why? What were his concerns? Was he worried only for himself or for his family as well?

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