EVOLUTION-II
Analysis of various PMTs from 2013-2017
2013
2014
2015
2016
2017
AIPMT/NEET
2
2
1
4
AIIMS
1
2
2
AMU
4
1
Kerala
1
2
K-CET
1
2
2
J & K
1
Class XII
- The various evidences of evolution ascertain that simple living organisms gradually
modified into complex forms. This idea of organic evolution dates back to 322
B.C. when Aristotle believed in a ladder-like gradation in nature and suggested
that there had been a gradual transition from the simple and imperfect to the
complex and perfect. Similarly, Buffon (1707-1788 A.D) the great French naturalist
was the first to propose the direct modifying influence of the environment. He is
therefore, also considered as the “Father of Evolutionary Concept”. - However, the first person to put forth an elaborate theory of organic evolution and
the origin of species by adaptations to environments was also a French naturalist,
Jean-Baptiste de Lamarck. Many more theories have been proposed later to explain
the concepts of organic evolution. - Some of the important theories to be discussed here are:
Lamarck’s theory
Darwin’s theory
Hugo de Vries’ theory
Synthetic theory of evolution
Theories of Evolution
LAMARCK’S THEORY
- Lamarck published his theory of evolution in ‘Philosophie Zoologique’ in 1809.
It is popularly known as ‘the inheritance of acquired characters in organisms’. It
can be defined as “the changes in structure or function of any organ acquired
during the life time of an individual in response to changes in the surrounding
environment are inherited by its offspring and keep on adding up over a period
of time”. - Thus, Lamarck stressed on adaptations as means of evolutionary modification.