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Describe how natural selection brings about adaptations of a species to its environment

Describe how natural selection brings about adaptations of a species to its environment.

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Masinde
Natural selection is any consistent difference in fitness among phenotypically different classes of biological species.Natural selection is a theory that accounts for the adaptations of organisms,those innumerable features that so wonderfully equip them for sur-vival and reproduction; it is this theory that accounts for the diver-gence of species from common ancestors and thus for the endless diversity of life.Adaptation refers to the process whereby the members of a population become better suited to some feature of their environment through change in a characteristic that affects their survival or reproduction.Adaptation is a feature that enhances the survival of organisms that bear it, relative to alternative character states.Natural selection is the mechanism that causes the evolution of adaptations.Therefore,adaptation is a characteristic that has evolved by natural selection.Natural selection leads to extinction. Variation of the genome that do not have the information required to survive in an environment are eliminated due to natural selection. The surviving genomes do have the information required to adapt to the environment.Natural selection does not create information necessary for the adaptation of a population. The information must readly exist for adaptation to occur. Natural selection will change the composition of a population by eliminating the poorly adapted.For example, the English peppered moth. Prior to the 19th century, the most common type of this moth was white-colored. Few peppered moths were black.As the Industrial Revolution changed the environment, the appearance of the peppered moth changed. The darker-colored moths, which were few, began to thrive in the urban atmosphere. Their black-sooty color blended in with the trees stained by industrial pollution. Birds could not see the dark moths, so they ate the white-colored moths instead. The population changed to being predominately dark. When the pollution caused by the Industrial revolution was brought under control the population reverted back to the predominately white variety.Natural selection only changed the population.Another example is the Cheetah of the Eastern African Savannah. The Cheetah that had the genetic information for speed survived and passed on that information to their offspring. There is now so little genetic variation in the Cheetah population that a change in the environment would not lead to further adaptation but to extinction of the Cheetah population.Natural selection does not create adaptations in a population but only chooses the existing adaptations best suited to a changing environment.
Mr Masinde answered the question on April 27, 2018 at 07:38

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