I.9.4 Natural selection can only act on systems that compete against each other in some way

In order for natural selection to be capable of acting, it is necessary that the developing systems compete against one another in at least some respects. The size of the population and thus the possibility of multiplying must be limited from without, either through the amount of energy or structural materials available or through elimination of some of the individuals from the population. The size of the population must be part of a regulation feedback cycle that keeps it within certain limits. Simultaneously, from the standpoint of natural selection (however, not from the standpoint of the direction in which it acts), it is not important whether the excess individuals are eliminated from the population according to some special criteria, i.e. preferentially the weaker, stupider or slower individuals, or whether they are eliminated quite at random, without respect to their biological quality.

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The classical Darwinian theory of evolution can explain the evolution of adaptive traits only in asexual organisms. The frozen plasticity theory is much more general: It can also explain the origin and evolution of adaptive traits in both asexual and sexual organisms Read more
Draft translation from: Evoluční biologie, 2. vydání (Evolutionary biology, 2nd edition), J. Flegr, Academia Prague 2009. The translation was not done by biologist, therefore any suggestion concerning proper scientific terminology and language usage are highly welcomed. You can send your comments to flegratcesnet [dot] cz. Thank you.