Identifica los postulados más importantes de los modelos sobre la evolución: Lamark, Darwin y la teoría sintética.
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Question: Identify the most important postulates of the models on evolution: Lamark, Darwin and synthetic theory.
These are evolution theories and here are their postulates:
Postulates of Lamark's theory of evolution:
1) Development of new needs: environmental factors in the environment of a living organism always changes. These changes require a change in behaviour of the organism in order to survive.
2) Use and disuse - the environmental changes cause some organs to be used more while some used less. The organs that are used often develop more while those are less used degenerate.
3) Inheritance: the changes that occur in the organism are inheritable and the new organism acquires them in order to survive in the new environment.
4) Speciation: Lamark proposed that new species are formed due to accumulation of inherited traits from generation to generation.
Postulates of Darwin's theory
1. Geometric increase - states that the multiplication of organisms occur at a rate that is not able to be supported by the environment.
2. Limited food and space - this is caused by the rapid multiplication of population of a given organism in an environment. In the end competition develops among the organisms for the limited food and space.
3. Struggle for existence - the competition results in the organisms struggling among themselves for survival. The competition is great in organisms that have similar requirements and can either be intraspecific( among the same species), interspecific ( among different species) or extraspecific ( between species and the environment).
4. Variations - the tendency of organism to adapt to their environment due to continuous and useful variations.
5. Natural selection - organisms that have attained the helpful variations and are best adapted to the strigent environment will survive. Also called survival for the fittest.
6. Inheritance of useful variations - organisms pass these useful variations to their offsprings.
7. Speciation - when these variations accumulate and inherited from generation to generation, new species are formed.
Postulates of Synthetic theory
1) Genetic variation - these is the difference in the genetic make up of organisms caused by mutation, genetic drift, hybridization (interbreeding) and recombination of genes.
2) Natural selection - in synthetic theory, natural selection occurs when the individuals that are best adapted to the environment produce more than those that are less adapted. This leads to accumulation of the "better genes"
3) Reproductive isolation - this occurs when the organisms with the better genes are preferred for reproduction. This increases the reproduction of the better genes in the environment.