Random fertilization is one of the three dominant fertilization mechanisms used by organisms undergoing sexual reproduction. The other mechanisms of producing offspring are independent assortment and crossing over. These mechanisms allow for diversity in the gene pool.
Random fertilization mechanism assumes that each gamete has an equal chance of fertilizing as any other gamete. For reproduction, a male gamete has to fertilize a female gamete in the fallopian tube, but any of the large number of male gametes have equal probability of carrying out this process. What this means is that the traits in the offspring are not pre-selected. They can any combination of traits depending on the chance fertilization of a particular male gamete with a female gamete. That is, a 'sweet tooth' gamete has as much chance as a 'non-sweet tooth' gamete of fertilizing a female gamete and hence, this random selection results in genetic diversity in population.
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