Lamarck's Vitalism

Vitalism was an evolutionary thought introduced by Jean Baptiste de Lamark(1744 - 1802). Vitalism was used to explain a species' ability to adapt; it is better known as the theory of inheritance and of acquired characteristics (it is important to note that the study of genetics was not yet known to Lamark and other scientists). According to Lamark, certain traits of a creature could come about via use or disuse. When a trait was used many times, the organs which the trait was dependent on were strengthened, and the trait became commonplace. If a trait fell into disuse the organ was weakened, and the trait was not carried on to its offspring. If a trait was strong within the parent, its offspring would also have the same characteristics. Lamarks vitalism has lent itself to many criticisms, of the more popularly known is how his theories apply to the example of the giraffe. According to a vitalist viewpoint, a giraffe's long neck came as a result of the use of the animals need for leaves on the tops of trees. Over time the giraffe's organs were strengthened to support long necks, and hence its offspring were also endowed long necks. This example has been likened to a human being, regardless of genetic makeup, simply going into a gym, lifting weights to strengthen their organs, and then being able to pass on those same strength traits they developed to their offspring. Similar to prior theorists, Lamark also proposed that certain organisms could be placed into different levels within nature, or the scala nature, thus organisms could be ranked in some way, shape, or form.