
Concept explainers
Discuss the two principles on which evolution is based.

To review:
The two principles on which evolution is based on.
Introduction:
Evolution is a slow process in which change in the characters, which can be inherited, is observed from generation to generation. These characters are the gene’s expression which is passed from parents to their offspring.
Explanation of Solution
Evolution is based on two principles. These two principles include genetic variation and natural selection. Genetic variation is present in the natural population. The offspring inherit various alleles from their parents that affect their phenotype. The allelic difference in the genes is caused by random mutation. Thus, the presence of various types of alleles influences the proteins and their functions, which are encoded by them and ultimately affects the phenotype of the individual.
Natural selection is the process of selecting the individuals that can tolerate the condition of the environment and also possess reproductive superiority. Species continue to reproduce and thus, there is a competition for survival. Those individuals, who have the most favorable traits to survive the competition and the environment, will dominate the population and will finally survive. The species which are fitter and well adapted to the environmental conditions and are more successful reproductively, will survive. Thus, this results in the formation of a new variety of species.
Therefore, it can be concluded that evolution is based on two principles which are genetic variation and natural selection. Genetic variation is the presence of various kinds of alleles, which are inherited by the offspring from their parents in the population which leads to variation. Natural selection is the process in which, the species that can endure environmental changes and is reproductively fit, survives.
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Chapter 29 Solutions
Genetics: Analysis and Principles
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