Question

Compare and contrast Lamarckian and Darwinian theories of evolution. Give an example of each. Do not use any examples addressing: giraffes, elephants, birds or humans. Be detailed in your answer(s).

Answer 1

Lamarckian theory of evolution.

Lamarckian inheritance explain the inheritance of the characteristics required by an organism during its lifetime to its offspring. Lamarck incorporated the action of soft inheritance into his evolutionary theories.

In simple words lamarckism is presented on two principles.They are USE and DISUSE where the useful characteristics in an organism development stabilize in the body and characters that are not useful tend to degenerate and disappear slowly and totally over a period of time.b) Inheritance of acquired traits: individuals not only inherit the traits of their ancestors but also those acquired during their lifetime.

DARWINIAN theory.

Darwin theory of evolution is the valley held notion that all life is related and has descended from a common ancestors and that all organisms are related. He proposed that beneficial mutations are inherited from one generation to the next generation. 3 observations of Darwin from the nature are a)Prodigality of observations b) Constancy of population c)Variations.

Comparing both theories.

Both theories accepted evolution and considered as common descent universally.

Both excluded biogenesis from their theories.

Both failed scientific method.

The both theories stated that all organisms are connected.

Life is changing gradually over time.

Both theories explained that life started with fewer simple organisms an Slater developed into complex organisms.

Differences.

Darwin explained about changes occuring in species while Lamarck made focus on the changes occur in individuals.

Darwin believed in extinction sure Lamarck didn't.

Darwin explained about the struggle for existence where as lamark does not explain struggle for existence.

Darwin theory is based on survival for fittest and lamarckian theory does not consider it.