Jean-Baptiste Lamarck created a theory before Darwin which began the ideology of evolution. His theory is called the "Lamarckism Theory". According to Lamarck, if an organism desires a certain trait or has a certain characteristic, its offspring will have that trait or characteristic. For example: If a human had lots of muscle from being very physically active, that humans child will have a lot of muscle as well.
Through biochemistry and the laws of physics, scientists declined this theory. Eventually, if a trait is not helping an organism survive and declining that species population, that certain trait will be eliminated. But it cannot occur as quick as one generation, it takes up to millions of years.
"Lamarckism." The Gale Encyclopedia of Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. 4th ed. Detroit: Gale, 2008. Gale Science In Context. Web. 19 Apr. 2011.
Darwin's Theory of Natural Selection:
Darwin's theory of natural selection acts to accumulate minor genetic changes to an organism to help them advance in survival. If a member of a species developed a "functional advantage", the offspring will inherit that advantage and pass it on to their own offspring. Darwin also explains how overpopulation helps natural selection causing the weak to die off or struggle to survive and only the strong or fittest surviving, in other words, survival of the fittest.
Example: Darwin and his famous study of finches- each had different types of beaks. The longer, stronger beak was more preferred compared to the shorter, weaker beaks. In order for an organism to grow, the less desired trait must die. Because the weaker, shorter beaked finches could not peck bugs out of the trees for food, they died off because of starvation. So the survival of the fittest comes into play, and therefore the "fittest" trait of the finches would be the stronger and longer beaked birds.
"Darwin's Theory Of Evolution." All About Science . N.p., n.d. Web. 19 Apr.
2011. <http://www.darwins-theory-of-evolution.com/>.
2011. <http://www.darwins-theory-of-evolution.com/>.
No comments:
Post a Comment