Evolution

Lamarcks Theory of Evolution and its Legacy



Tweet
Tea K. Everhart's image for:
"Lamarcks Theory of Evolution and its Legacy"
Caption: 
Location: 
Image by: 
©  

The discredited theory of heredity known has the inheritance of acquired traits was one that did not hold the position of accepted theory for long. Jean-Baptiste Lamarck (1744-1829) a supporter of that theory that had been around since ancient times. Although his views were incorrect, they were the first conclusions on the subject that gained attention by other scientists and were commonly accepted by everyone until years after Lamarck's death when Charles Darwin appeared bringing along the Theory of Evolution by means of Natural Selection and other scientists found his theories to be correct. Even though Lamarck is credited for having been the creator of the theory, he was not. In reality, Lamarck had very few original ideas but is portrayed as the figure in history to have developed them.
Many are taught in school that the sole difference between Lamarck and Darwin is that one embraced this theory and the other rejected it. Lamarck adopted the inheritance of acquired characteristics as an assumption, but it was an assumption about heredity, not about evolution. Charles Darwin also accepted the theory to an extent and Darwin even thought that there was some experimental evidence to support it.
The theory (Lamarckism) stated that the changes in physiology acquired over the life of an organism are passed down to the offspring. An example would be like the docked tail of a dog or the loss of an apes' finger. Many scientists who had supported Lamarck's theory proved him wrong when doing experiments to prove him right. In the 1800's, a German Zoologist named August Weisman was one of the many who had supported the theory only to convince himself that it was wrong.

According to Lamarck's theory, evolution involved two principles:
He called his first principle the law of use and disuse.
The second part of Lamarck's theory was the inheritance of acquired characteristics. Lamarck assumed that the characteristics an organism developed through use and disuse could be passed on to its offspring.

Today we know that acquired traits do not affect an organism's genome and that the genome is the only thing that gets passed on to offspring. With this being true, there is no way for an acquired trait to be passed onto the offspring. Only a trait that affected an organism's genetic makeup appear naturally in its offspring.

Tweet
More about this author: Tea K. Everhart

From Around the Web




ARTICLE SOURCES AND CITATIONS