Charles Darwin’s influences on the Theory of Evolution


What was Jean-Baptiste Lamarck’s theory of evolution?
Jean-Baptiste Lamarck was the first person credited with explaining the evolution process. In his work, he explained that if the surrounding environment changed, the animal would develop new characteristics to match its surroundings. His view on evolution is if an animal does not use a part of the body, then the animal will lose that body part. Lamarck’s theory is known as the inheritance of acquired characteristics, also known as use-disuse theory. The most recognized hypothetical provided for this theory involving giraffe’s necks. The theory goes that if the lower branches of trees were stripped of their leaves, the animal would have to reach its neck higher towards the top branches. Thus causing the animals neck to stretch and become longer, and passing this new trait along to its offspring. To learn more about Jean- Baptiste Lamarck’s theory visit: https://evolution.berkeley.edu/evolibrary/article/history_09

How did Jean-Baptiste Lamarck contribute to the theory of evolution?
A key point to causing evolution to succeed is, in order for traits to evolve and change, they MUST be heritable. For the reason that, physical change in an animals characteristic is not passed on to offspring genetically the use-disuse theory has been proven to be incorrect. Lamarck’s theory lead to the idea of natural selection, the idea that animals better adapted to their environment will survive and produce off spring. The surviving animal’s defining characteristics are passed to its offspring genetically. Relating back to the giraffe hypothetical, Darwin’s theory of natural selection would suggest that giraffes with short necks would become extinct, while giraffes with long necks survive and create offspring. Resulting in all giraffes having longer necks.

A world without the use-disuse theory.
Without Lamarck’s theory, Charles Darwin would have been able to complete his evolution work. The Galapagos finches would still been around and proved him with the evidence of natural selection. Darwin’s colleague John Gould would have still identified the variations of the bird’s beaks that lead to Darwin’s discovery of natural selection.


The one thing holding back Darwin. 
Beginning in the fifth century, the Catholic Church was in power over education and beliefs as well as in control of the law. Defying the beliefs of Catholic Church during the middle ages would have resulted in one’s insufferable death, resulting in the church’s word believed as true. The church’s view on how humans came to be was through the creation of God, resulting in what is now known as fixity of species. Fixity of species is used to notion that once a being is created it never changes, thus being the opposite of the theory of evolution. At first, Darwin did not publish his findings fearing he did not have enough evidence to back his theory. The main reason halting Darwin’s publishing was his family’s involvement in the church. He along with his family and friends were worried that because his findings provided a different view of the churches; he could be severely punished.


Comments

  1. Jacklyn van der ColffFebruary 7, 2019 at 4:11 PM

    Hi,
    I found you response insightful and I came to the same conclusion that Lamarck was the biggest influencer of Darwin. The infographics that you used worked nicely with your points and clarified the theories. I also liked the finch diagram and the explantion you provided on how it reltaed back to natural selection. Lastly, the explanation of why he did not publish his findings was very insightful about what the church believed, which was a unique perspective.

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  2. Hi Kayla,
    First of all- great blog name, totally love it! Also, I truly enjoyed reading your post. Your explanation was very well-written and although I chose to write my post on Malthus, you certainly helped me learn more about how big of an influence Lamarck had on Darwin. Your breakdown of why Darwin feared releasing his findings due to the church's thoughts was exceptional. You definitely were more specific in explaining the exact thoughts and feelings that surrounded that entire situation than I was. Thanks for sharing!

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  3. First impression: Great images!

    Excellent description of Lamarck's theory.

    A couple of points in your next section:

    "For the reason that, physical change in an animals characteristic is not passed on to offspring genetically the use-disuse theory has been proven to be incorrect."

    We know this now, but at the time, Mendel had not yet developed his work on genetics, so NO ONE knew of this problem. Lamarck certainly did understand that inheritance of some sort was necessary. He relied upon it to transmit the changes in an individual to their offspring.

    "Lamarck’s theory lead to the idea of natural selection, the idea that animals better adapted to their environment will survive and produce off spring."

    I don't think that is an accurate claim. By the time Darwin was in school, Lamarck's work had already been debunked and it was just a part of the history of natural science. It was foundational at most. If you have evidence that Darwin started off with Lamarck's ideas and directly used them to develop natural selection, please do cite the source. That would be fascinating reading.

    But there are two more bullet points that I would include here. In addition to heredity, Lamarck also emphasized the importance of a changing environment and of reproduction to allow evolution to occur.

    I agree with your conclusion and reasoning in the next section. Lamarck should be credited as the first to propose an actual mechanism for evolution. This was a huge step forward, regardless of its inaccuracies, but there were many others discussing and debating evolution during Darwin's time. Lamarck was important but not necessarily indispensable.

    The church involved here was the Anglican Church of England, not the Catholic church.

    "he could be severely punished. "

    How so? The Church of England was not burning anyone alive or putting them under house arrest. But that doesn't mean they couldn't have made Darwin's life difficult for him, socially or professionally. He delayed publishing his work for more than two decades (only publishing when forced to do so by Wallace), so it is worth trying to understand what worried him so much. Was he only worried about himself or was he also worried about how his family might be impacted by publishing? Remember that his wife was very devout. How might she have been impacted if the church responded negatively to Darwin? Remember that scientists don't work in a vacuum. They can be influenced not just by academics but also by social, cultural and personal issues.

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