Asexual reproduction is advantageous to organisms such as plants and sea sponges for various reasons.
Plants are producers in the food pyramid, therefore it's required that there is an abundant amount of them for the primary consumers to gain the first layer of energy. If there were a scarce amount of these producers, the entire system would collapse for whatever food chain or web that the producer is in.
On top of that, it ensures the safety of their species population and allows them to grow in numbers rapidly.
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