Jean-Baptiste Lamarck VS. Charles Darwin
I believe Jean-Baptiste Lamarck contributed to the theory of evolution, by disagreeing with what Darwin had believed. In the end it helped prove Darwin's theory. Lamarck believed that species adapted to their environment, and due to the species adapting, they would pass these "traits" on to their offspring. For instance he stated that "If a giraffe stretched its neck for leaves, a "nervous fluid" would flow into its neck and make it longer. Its offspring would inherit the longer neck, and it would continue to stretch more over generations" Early Concepts of Evolution: Jean Baptiste Lamarck, evolution.berkeley.edu/evolibrary/article/history_09. Darwin believed this wasn't true, we are basically products of our environment, and adapt to the changes taking place in our environment. These traits were then passed on to our offspring and only the strongest survived. Birds and mammals all have differences, some with short beaks, some with long, the ones that adapted to their environment would live on and pass these traits on, while those that didn't adapt would die off.
- All organisms have the potential of reproducing exponentially. If a Giraffes neck grew and grew longer over generations, a giraffes neck would never stop growing and the exponentially growth of a giraffes neck would make the giraffe all neck and nothing else. One would think a giraffe would lose the ability to walk over the years. Luckily Lamarck's theory wasn't true.
- What is preventing organisms from reproducing at their potential? Giraffes necks only have seven vertebrae, they have stretched these vertebrae to their potential, which allows for no more stretching, so the theory that Lamarck has that they would keep growing, generation after generation, is physically impossible.
- Resources are limited: If a giraffes neck continued to grow, they would become so top heavy, they wouldn't be able to stand, sure they could eat from high trees, but would they be able to stand under all that weight?
- Organisms with better access to resources will be more successful in their reproductive efforts. The giraffes will have access to food other animals can't reach, and they will be able to reproduce as long as their body are proportioned.
- Who gets better access to these limited resources? Darwin's giraffes would get much more from the resources as they would adapt perfectly to their environment, and be able to utilize the resources given to them. They also wouldn't have a lot of predators being as large as they are. Darwin's giraffes would also have greater reproduction success.
- If the environment changes, the traits that are helpful or adaptive to that environment will be different: The species would have to adapt to new changes in the environment, if they do not, they will fail to have reproductive success and the traits that make them successful in today's world. If they failed to adapt, they could possibly die off.
- In order for natural selection to occur, reproduction MUST occur! If the species failed to adapt to changes, and they failed to reproduce, they would die off, and become extinct. They need to be able to pass on their traits, to keep the species alive.
- In order for traits to evolve and change, they MUST be heritable. Lamarck believed traits changed and were acquired over a individuals lifetime, and that this individual would pass these traits on to their offspring, but it's actually genetics that passes the traits on. They can be passed on to generations years from now.
- Individuals do not evolve. Populations do. Individuals will not see the evolving of different species, as their life is not long enough. It takes years to evolve, so future generations will witness the changes.
- Artificial selection is identical to natural selection with one important difference. Humans intervene, and are selective. Natural selection happens naturally.
- Could Darwin have developed his theory of natural selection without the influence and ideas of this individual? Explain. Yes, he could have, as his theory was proven to be correct while Lamarcks was not. Lamarck believed an animal wanted to evolve, for instance a giraffe reaching higher for food- therefore stretching his neck. Darwin believed this to be untrue, that they adapted to their environment. Evolution does not have a plan, it just happens.
- How did the attitude of the church affect Darwin and his decision to publish his theory? It kind of caused condemnation and approval, causing a divide among the church. Some were supportive of his ideas and others were completely against it. Darwin was able to get support from other scientists and eventually published his work.
"I believe Jean-Baptiste Lamarck contributed to the theory of evolution, by disagreeing with what Darwin had believed"
ReplyDeleteI'm confused with this claim. Darwin developed his mechanism long after Lamarck developed his. So how could Lamarck disagree with Darwin? Darwin was born the year Lamarck published his paper. Be aware of the temporal factors involved here.
That said, I do appreciate how you describe the differences between Lamarck's and Darwin's mechanism.
Bullet point section: Not all of these can be directly attributed to Lamarck. There are three (possibly four) that you can tie directly to Lamarck's evolutionary mechanism. One would be the importance of the environment on natural evolution. Another would be the importance of reproduction to evolution, along with the requirement that traits be heritable in some way. Additionally, I would also have included the point that "individuals don't evolve. Populations do", not because this was Lamarck's point but because he argued the opposite. Darwin recognized the problem with Lamarck's logic and countered it, so this could be viewed as a negative, oppositional influence by Lamarck.
Format issues popped in at the end, with your final two sections getting lumped in with the other bullet points. You can always go in and edit your post if it doesn't publish correctly.
I agree with your reasoning in the next section and I agree that Darwin may well have developed his theory without Lamarck's influence... but then I wonder if perhaps a different scientist might have been a better choice for this assignment? Make sure you take a look at other student posts to review how other scientists influenced Darwin and see if you change your mind on this.
" It kind of caused condemnation and approval, causing a divide among the church."
Actually, the church didn't know Darwin existed until after he published, though that doesn't mean the church didn't play a role in Darwin's decision to delay. Remember that this question is about Darwin's decision to publish, not what happened *after* he published. Darwin delayed publishing for more than 20 years. The question is, why? And how did the influence of the church play a role in this delay? What were Darwin's concerns? And was he only worried about himself or was he also worried about how his family might be impacted by publishing? Recognize 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.