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Updated: Jul 12, 2026

Experimental Manipulation of Body Size to Estimate Morphological Scaling Relationships in Drosophila
Published on: October 1, 2011
[Genetic explanation for vertical evolution]
1State Research Institute of Genetics and Selection of Industrial Microorganisms, Moscow, 113545 Russia. sukhodol@genetika.ru
Abstract:
The genetic theory of natural selection proposed by Fisher takes into account differential reproduction success of organisms, which may be estimated by using the Malthusian parameter as fitness. However, the minimum possible value of this parameter depends on ecological stability of an organism, which determines the probability of the survival and participation in reproduction for each viable offspring. In the course of vertical evolution, leading to an increase in the level of biological organization, ecological stability of organisms increases, and this might be accompanied by a decrease in their fitness. In the macroevolutionary process, alterations in ecological stability of organisms, including those responsible for an increase in the level of biological organization, are basic and primary changes whereas alterations in fitness are additional and secondary.
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