Question

Jean-Baptiste Lamarck who was alive prior to Darwin (pre-Darwin evolutionary theory) and has left a legacy important for development of evolutionary theory. From the perspective of a modern evolutionary theorist, write an ~1000 words obituary of this scientist in your own word. Also, highlight and explain the significance for contemporary evolutionary theory of the discoveries made by this scientist.

TYPED ANSWERS.
PLEASE REFERENCE ARTICLES USED
***NO PLAGIARISM PLEASE****

Answer 1

Answer:                This question i have to write pointswise,because,it's easy to understand you......

• Jean baptiste Lamarck was not only the evolutionary theorist , he was a institution in himself. His theories came at the time when there were no proper theories present regarding evolution.

• So it can be said that he created a benchmark for all the coming scientists. From the very beginning he was in love with nature and his deep bonding helped to formulate his theories of "use and disuse of organs".

• In very simple words he described that whatever is used grows and whatever is not used is discarded. This information somehow passes to the subsequent generations and thus a new trait either of under production or overproduction is continued.

• This was the beginning of "Lamarckism".This rule -- that use or disuse causes structures to enlarge or shrink -- Lamarck called the "First Law" in his book Philosophie zoologique.

• Lamarck's "Second Law" stated that all such changes were heritable. For example, Lamarck believed that elephants all used to have short trunks.

• When there was no food or water that they could reach with their short trunks, they stretched their trunks to reach the water and branches, and their offspring inherited long trunks.

• Lamarck also said that body parts that are not being used, such as the human appendix and little toes are gradually disappearing. Eventually, people will be born without these parts.

• Lamarck also believed that evolution happens according to a predetermined plan and that the results have already been decided.

• While the approach of Lamarckian theories was tremendously different from Darwinin theories but the end result was same: adaptive change in lineages, ultimately driven by environmental change, over long periods of time.

• It is interesting to note that Lamarck cited in support of his theory of evolution many of the same lines of evidence that Darwin was to use in the Origin of Species.

• Lamarck's Philosophie zoologique mentions the great variety of animal and plant forms produced under human cultivatioIn several other respects, the theory of Lamarck differs from modern evolutionary theory.

• Lamarck viewed evolution as a process of increasing complexity and "perfection," not driven by chance; as he wrote in Philosophie zoologique, "Nature, in producing in succession every species of animal, and beginning with the least perfect or simplest to end her work with the most perfect, has gradually complicated their structure." Lamarck did not believe in extinction: for him, species that disappeared did so because they evolved into different species.

• If this goes on for too long, it would mean the disappearance of less "perfect" organisms; Lamarck had to postulate that simple organisms, such as protists, were constantly being spontaneously generated.

• et despite these differences, Lamarck made a major contribution to evolutionarythought, developing a theory that paralleled Darwin's in many respects.

• Rediscovered in the middle part of the 19th century, his theories finally gained the attention they merited.

• His mechanism of evolution remained a popular alternative to Darwinian selection until the beginning of the 20th century.

• Among the most popular alternatives were theories involving the inheritance of characteristics acquired during an organism's lifetime.
• Scientists who felt that such Lamarckian mechanisms were the key to evolution were called neo-Lamarckians.
• With the development of the modern synthesis of the theory of evolution and a lack of evidence for a mechanism for acquiring and passing on new characteristics, or even their heritability, Lamarckism largely fell from favor.
• Unlike neo-Darwinism, the term neo-Lamarckism refers more to a loose grouping of largely heterodox theories and mechanisms that emerged after Lamarck's time, than to any coherent body of theoretical work.
• In essence, a change in the environment brings about change in "needs" (besoins), resulting in change in behavior, bringing change in organ usage and development, bringing change in form over time—and thus the gradual transmutation of the species.

                                                            Please Rate My Answer.........Thank........u.......