2016年10月30日 · Variation is the raw material on which evolutionary force of natural selection can act. Variations are mainly manifestations of small genetic differences among organisms of same species. Genetic variations add diversity to life. Variations arise randomly due to mutation of genes. Various forms of genes are called alleles which arise due to mutation and these are inheritable. Generally ...

2017年6月7日 · A good question, and the short answer is, it depends. In many and probably most cases, no, natural selection usually decreases genetic diversity. Why? Well it depends on the environment- if conditions are the same throughout the area where a species is found, then one particular type will be at an advantage, and individuals which are different from that will be disadvantaged and not pass on ...

2018年4月10日 · Natural selection is wrong as a cause of adaptation. Natural selection was proposed as the means by which descent with modification had caused the great variation of life observed in the world today. Modern empirical science has shown that natural selection working alone can not explain the hypothesis of descent with modification. That natural selection occurs is not an issue. The movement ...

2014年8月20日 · Variation in a population often results from natural selection, random genetic drift, emigration, or ...

2016年1月8日 · Variation, inheritance, high rate of population's growth, differential survival and reproduction. Variation : Within a population, some traits can be expressed in various ways and make individuals look and behave differently. It can be hair color, body size, eyes color, reaction while facing a danger, ... Inheritance: Heritable traits are transmitted to …

2018年3月8日 · Natural selection preserves variations that are best suited to environment. An example of natural selection selecting variations best suited to the environment, is the peppered moths of England. There were two variations of the moth, one dark or melanic and the other white. Before the industrial revolution the white variation was dominate.

2018年3月14日 · Variation is important for a species to develop specific traits that can allow them to gain immunity/protection from a specific environmental factors like a disease or predator. This helps with survival rates.

2016年9月13日 · This loss of natural variation can lead to the extinction of the species if there is a major change in the environment. The lesser the amount of natural variation the greater chance of the extinction of the species. The likelihood of survival decreases with the a decrease in variation.

2015年12月11日 · Natural selections acts on the phenotype and the phenotype is the the result of the interaction between genotype and environment In a population, the natural selection will favour the individuals with the higher fitness (In other words : the ones which have the best chances to survive and reproduce) in a given environment. Natural selection take effect on the phenotypic level. Also, remember ...

2016年11月2日 · The possibility of continued evolution is critically dependent on renewed variation. For a given population , there are three sources of variation : Mutation Recombination Immigration of genes. Mutation Mutation rates are so low that mutation alone cannot account for the rapid evolution of population and species. However, recombination by itself does not produce variation, and immigration ...