Videos Related with Lamarck’s Theory of Evolution

Note on Lamarck’s Theory of Evolution

  • Note
  • Things to remember
  • Videos
  • Exercise
  • Quiz

Jean Baptise de Lamarck of France, Alfred Russel Wallace and Charles Darwin of England and Hugo De Vries of Holland are the main contributors to the theory of evolution.

The major theories of evolution are:

  1. Lamarck’s theory or Lamarckism
  2. Darwin’s theory or Darwinism

Lamarck’s theory or Lamarckism

Jean Baptise de Lamarc
Jean Baptise de Lamarck

Jean Baptise de Lamarck of France is biologist and philosopher. He proposed Lamarckism in his book philosophic zoologique in 1809 AD. This theory can be explained in the following points:

  1. Direct environmental effect: According to Lamarck, the environment directly influences the modification of the organs in organisms. He believed that due to the changed environment, there is a new need for the organism which modifies the organs of the organism.
  2. Use and disuse of organs: A constant use and disuse of the organs lead to the gradual weakening of the organs. A constant use and disuse of organs lead to its modification in the form and less used structures reduced and ultimately gets lost.
  3. Inheritance of acquired characters: The characters obtained by an organism by an organism by direct environmental effect and use and disuse of the organs are called acquired characters. The acquired characters are inherited from one generation to another and new species are originated after a series of generations.

Criticism of Lamarckism

  1. Lamarck has not proved experimentally that use and disuse of organs can modify them.
  2. It is absolutely incorrect that new organs can be developed according to the need and wish of the organism.
  3. All the require characters are not inherited into the new generation.

  • According to Lamarck, the environment directly influences the modification of the organs in organisms.
  • A constant use and disuse of organs leads to its modification in the form and less used structures reduced and ultimately gets lost.
  • The characters obtained by an organism by an organism by direct environmental effect and use and disuse of the organs are called acquired characters.
.

Very Short Questions

According to the Lamarckism, the present long necked giraffe has been evolved from the ancestral short necked giraffes. When there was the lack of food in the ground the giraffe tried to survive by eating the foliage of trees by continuous stretching of their neck. Due to this, in the next generation, the giraffes were produced with a long neck. Thus, continuous use of their organ and inheritance of the variation lead finally the giraffe with the long necks.

In 1908, Lamarck put forward his view as follows:
a) Environmental influence on organisms
b) Variation in the structure of body due to use and disuse of organs
c) Transfer of acquired characteristics from one generation to another.
Lamarck's view regarding the environmental influence on evolution of organisms is very important. Plants and animals living in different habitats and environment also have differences in their body structures. The variation occurred in the body structure of an organism due to the influence of environment is transferred from one generation to another generation. Such type of variation depends on the use and disuse of organs by the organisms. For example, the long necked giraffe evolved from its short necked ancestor. Similarly, the fish inhabiting in deep and dark bottom of the sea are blind due to the disuse of their eyes. The organ which is not in use disappears gradually.

Lamarck's theory is not accepted universally due to the following reasons:
a) The change in the structure of a body by the use and disuse of organs is not manifested practically.
b) The new organs can be formed according to the will of organisms', this has been found practically.
c) The symptoms of growing very small or very large are not observed in the evolutionary trend of organisms.
d) The offspring's of a tail-trimmed dog instead of being short tailed are actually like normal dogs.

The theories of evolution are:

(1) Theory of special creation.
(2) Theory of spontaneous generation.
(3)Modern concept of origin of life.

French biologist and philosopherJean Baptise de Lamarck is the founder of the theory "Use and diuse of organs". A constant use and disuse of organs leads to its modification in the form and less used structures reduced and ultimately gets lost.

0%
  • Who are the main contributors to the theory of evolution?

    Charles Darwin
    All of them
    Jean Baptise de Lamarck
    Alfred Russel Wallace
  • When was the Jean Baptise de Lamarck proposed Lamarckism in his book philosophic zoologique?

    in 1809 AD.


    in 1899 AD.


    in 1819 AD.


    in 1819 AD.


  • The process of gradual and orderly change in organisms from one form to another is called _______.

    organic evolution


    genetic evolution


    inorganic evolution


    general evolution


  • Development of living thing from non-living matter is ______.

    abiogenesis


    aborigines


    species


    abestos


  • The technique of finding the age of fossils is called ______.

    phalanges


    carbon-dating


    phylogeny


    paleontology


  • You scored /5


    Take test again

DISCUSSIONS ABOUT THIS NOTE

You must login to reply

Forum Time Replies Report
sk

what is lamarckism


You must login to reply