Larmarckism
Lamarck's view of evolutionary change through use and disuse is different from our current understanding in multiple ways. One thing this theory suggests is that the organs, structures, and traits that we do not use or benefit from would go away, but this has not happened. Humans still have vestigial structures that are pretty much useless for us to be able to function. A few examples of these vestigial structures are the appendix, wisdom teeth, as well as tails (in embryo development). These are all useless to have, and if Lamarck's theory of use and disuse were correct, then these structures would have been weeded out a long time ago. It would make sense that these useless traits would disappear over time since they seem to be a waste of energy and resources in our body, yet they still exist. These components have repeatedly shown up for hundreds of thousands of years and were likely important to some of our early ancestors. This lack of understanding of DNA and heritability is something that Lamarck's theory lacked.
One aspect of this theory that I agree with is how things we do in our lifetime can affect what traits we pass on to our children. For example, DNA mutations that we acquire as we live will have the chance to be passed on to our children and can affect their DNA. While Lamarck had the famous theory about giraffe's necks that we now know to be incorrect, there are some aspects of this theory to be true in humans and other organisms. We change as we grow older and our life choices we make will affect how we function. For example, if we do not take care of our bodies then we can get diseases that can affect how well we live our life. However, if we stay healthy then we will have a better chance and producing healthy offspring who will be able to do the same. While giraffes' necks may not grow like Lamarck suggested, he was right in assuming that the actions an organism makes will affect their life, ability to survive, and what they will pass on to their children.
Sources
https://www.livescience.com/21513-vestigial-organs.html
I like how you talked about specific organs that our bodies cannot physically remove by itself disproving the disuse way of thinking Lamarck had. Considering I just had surgery to remove my wisdom teeth I wish our bodies did that!
ReplyDeleteAshley, great job pointing out Lamarck's stance on the use/disuse of organs. It's really interesting to think about how we could potentially manipulate this idea if it were to be true. I do have a question though. Did Lamarck say that we would lose these structures, or did he say that they would get smaller and smaller until they were hardly noticeable? If the second case were to be correct, could we dismiss Lamarck's ideas on evolution so easily?
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