engleski

Quantitative genetics and evolution

Today, evolution is a unifying concept in biology. A century and half ago, Darwin developed the theory of natural selection, and proposed it as the main mechanism of evolution. A quantitative approach to the study of evolution required new theoretical developments in population and quantitative genetics. Here, I review the basic concepts of quantitative genetics neccessary to understand microevolutionary change. Natural selection is a consequence of differences in fitness (reproductive success) between individuals in a population. But natural selection is not equal to evolution. In order to achieve evolutionary change, variation in fitness must be heritable, i. e. it must be transmited by genes from parents to offspring. Besides fitness differences, individuals within a population often differ in many other characters (morphological, physiological and behavioural) which are also genetically transmited from generation to generation. It is crucial to distinguish the process of selection which operates in an existing generation from the evolutionary change which is visible in the next generation. Most concepts of quantitative genetics centre around variances and covariances, and include the evolutionary potential of a population or heritability (ratio of additive genetic variance and phenotypic variance), the strength of selection on a particular trait (covariance of particular trait and fitness), the total strength of selection (phenotypic variance in fitness) and evolutionary response (phenotypic change in the next generation) which can be predicted by breeder's equation.

quantitative genetics ; evolution ; heritability ; breeder's equation

nije evidentirano