asexual reproduction

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Reproduction that does not involve the manufacture and fusion of sex cells (gametes) from two parents. Asexual reproduction has advantages in that there is no need to search for a mate; every asexual organism can reproduce on its own. Asexual reproduction can therefore lead to a rapid population build-up. However, every new organism produced by asexual reproduction is genetically identical to the parent – a clone.

In evolutionary terms, the disadvantage of asexual reproduction arises from the fact that only identical individuals (clones) are produced – there is no variation. In agriculture and horticulture, where standardized production is needed, this is useful. Taking cuttings of a good variety of fruit tree is an example of artificial asexual reproduction. However, in the wild, an asexual population that cannot adapt to a changing environment or evolve defences against a new disease is at risk of extinction. Many asexually reproducing organisms are therefore capable of reproducing sexually as well.

Asexual reproduction is very common in micro-organisms. But there are also many plants that use it naturally. The blackberry or bramble spreads by allowing its stems to root where they touch the ground. However, the blackberry also reproduces sexually using its flowers.