Organisms that reproduce asexually have less chances for genetic mutation and genetic drift, meaning that if something is introduced into the environment that causes the organism to be unable to survive, it wont have a variation that might make it possible to live.
If they reproduce asexually, there is no way the parent has a genetic illness and the son doesn't have it (unlike those that reproduce sexually). Plus the reason shown by Moley :)
Asexual reproduction can be a disadvantage in unstable environments due to the lack of genetic variation, which limits adaptability to changes. While these organisms can reproduce rapidly, their clones may not survive if environmental conditions shift. In contrast, sexual reproduction offers greater genetic diversity, enhancing species' ability to adapt and survive in unpredictable conditions.
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