Jean+Lamarck

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=By Mason Burks= =//**__Jean-Baptiste Pierre Antoine de Monet Chevalier de Lamarck__**//= //**__August 1st, 1744 --- December 18th 1829__**//

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Jean-Baptiste Pierre Antoine de Monet Chevalier de Lamarck (henceforth referred to as "Lamarck") was a major proponent and thinker in the field of evolution in the 18th and 19th centuries, as well as a renowned biologist and academic. Lamarck was French (obviously). Lamarck contributed the theories of soft inheritance and adaptation through use and disuse, together known as Lamarckism. Though discredited in the modern day, Lamarck 's theories paved the way for future theorists such as Charles Darwin, and were the first true theories that involve what is now known as evolution.

Born in Northern France to a large family, Lamarck volunteered for the French army, as was customary in his family. During the Prussian Wars, Lamarck's commander was killed and he assumed command, despite being an inexperienced 17 year old. He proved his skill and courage, and after discharge from the army, he set off to find a career, meddling in medicine, botany, and banking, before he became a biologist and naturalist. Over time, his observations and theories made him a respected member of the scientific community, gaining membership to the French Academy of Sciences, and earning him a commission as the Royal Botanist. After the French Revolution, Lamarck became a professor of invertebrate zoology and a proponent of essentialism, which claims that all species are unchanging. His opinions, however, were changed as he further studied invertebrates in 1798. Once his firm belief in the change of the nature of species' over time had been established, he began searching for an explanation as to why. In the years of his search, Lamarck also became a renowned taxonomist, and was the first to separate crustaceans from arachnids from insects, placing them in different classifications. He also proposed a theory as to the movements of continents- Lamarck believed that universal winds going east to west picks up particles from the eastern coast of a continent and, over time, deposited it on the western side of the land mass, causing continents to gradually move westward. In 1802, four years after his search began, Lamarck published a book outlining his ideas of evolution, but was ridiculed by contemporary scientists.

As Lamarck grew old, he became blind, and died on December 18th, 1829. At the time of his death, his family was so impoverished that they had to apply to the Academy of Sciences for financial assistance. Despite this, all of Lamarck's belongings were sold at auction and his body was buried in a lime pit.

Lamarck's theory of evolution is as follows- that traits acquired throughout the life of a creature would be passed on to its offspring. An example of this would be a leg atrophying from disuse, eventually disappearing all together, or an arm growing larger as its muscle mass increased due to use. This use/disuse theory of evolution is now discredited, but proved a valuable starting point for later thinkers who would build upon previous ideas to find the truth. Lamarck believed that there were precisely two forces at work that shaped the nature and direction of evolution in any and every organism. Firstly is the Complexity Force. This, as Lamarck believed, was the tendency for creatures to evolve towards an increasingly sophisticated and complex end goal as time goes on. This end goal was thought by many to be humans- other thinkers denied the existence of a single end goal of evolution and felt that increase to complexity was a general idea and there was no final product. The second force is the Adaptive Force, as outlined in soft inheritance. A giraffe, for example, was thought to have started as a horse-like creature. It began to stretch its neck to reach more food, and these small stretches accumulated in a lengthy neck over time. Traits beneficial to survival would be passed on and further advanced, while unhelpful things would not be used, and would whither away and eventually disappear.



While Lamarck's theories on evolution have been disproven, they still hold much significance in terms of scientific advancement- he was the first to propose that traits were passed on from parent to offspring, and that beneficial traits would be passed on while unhelpful ones neglected and sometimes lost.

RESOURCES https://gs1.wac.edgecastcdn.net/8019B6/data.tumblr.com/tumblr_m91a4wxuSl1r8x2ybo1_500.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/f/f0/Jean-baptiste_lamarck2.jpg/220px-Jean-baptiste_lamarck2.jpg

Early Concepts of Evolution: Jean Baptiste Lamarck. (n.d.). //Understanding Evolution//. Retrieved January 18, 2013, from http://evolution.berkeley.edu/evolibrary/article/history_09

Jean-Baptiste Lamarck. (2013, January 15). //Wikipedia, The Free Encyclopedia//. Retrieved January 17, 2013, from https://en.wikipedia.org/wiki/Jean-Baptiste_Lamarck

Jean-Baptiste Lamarck (1744-1829). (n.d.). //UCMP - University of California Museum of Paleontology//. Retrieved January 18, 2013, from http://www.ucmp.berkeley.edu/history/lamarck.html