“Only variations that confer an advantage on an individual organism will survive in a population.” Justify this statement.
In sexual reproduction, there is formation and fusion of gametes. Due to recombination of genes, variations occur and they are heritable too.
In asexual reproduction, the organisms produced are exact copies of their parents. So, they have identical set of chromosomes and show little variations. They tend to preserve similarities among all the individuals also. Therefore, no more variations occur. This cause of variation influences evolution of those organisms which reproduce sexually. By it more and more variations are produced in next generations. Hence genetic drift will accumulate which causes formation of new species.