Natural selection as an evolutionary mechanism

Lamarck's theory of evolution

Darwin's theory of evolution

Theory: Charles Darwin, through his observations made during a 5-year voyage on the Beagle, published his conclusions on the theory of evolution in a book entitled on the origins of species.

He proposed the principle of use and disuse of organs, according to which, the development of structures and organs of an individual depends on the use that he did of them.

Lamarck is best known for his Theory of the inheritance of acquired characteristics, first presented in 1801, If an organism changes during life to adapt to its environment, these changes are passed on to their offspring.

In 1809, Lamarck, the French naturalist, proposed that changes in the enviroment generate needs among living beings, which changed to adapt to their enviroment.
Could acquire or inherit from preceding generations, respond to the requirements that their enviroment, inheritance of acquired characteristics.

This theory states that organs are acquired or lost as a result of use or disuse and that the characters acquired by a living being are inherited by their descendants.

Evolution process: Charles Darwin says that the natural causes populations to adapt or become more and more suitable to their environment over time. Natural selection is environment-dependent and requires that heritable variations exist in a group.

It was 180 years ago and until today, no one had been able to refute that evolutionary theory, he assumed that they would be the first links in the evolutionary chain of the flame and so he made it known. He christened her Macrauchenia. Now, 180 years after the Macrauchenia was listed as a great llama, the mastodon was a distant relative of horses, tapirs, and rhinos, known in lingo as the Perissodactyla family. Those animals were herbivores that inhabited much of South America before the Ice Age completely ended them 12,000 years ago.


In summary

Lamarck in his theory proposed that life evolved successively as individuals of a species change their situation, climate, way of being or habit, thus receiving influences that gradually change the consistency and proportions of its parts.

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Giraffe evolution theory

According to him, giraffes evolved to achieve a longer neck because they could not reach the leaves that constitute their food. Thus, little by little, the influence of the environment makes giraffes have an increasingly long neck, according to this theory of evolution according to Lamarck, which is based on the nature of animals, one of them the giraffe evolved by the need to eat leaves of very tall trees

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Theory-of-Natural-Selection

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