XXVI.4.1 The rate of anagenetic changes can be measured on the basis of quantitative and qualitative traits, as well as on the basis of the rate at which species or higher taxa emerge and disappear
There are, in principle, several different ways in which the rate of evolutionary processes can be measured.For anagenetic changes relating to quantitative traits, a change in the magnitude of the particular trait in time can be measured.For qualitative traits, the number of new traits (new evolutionary features) that emerged in the particular line over a certain time interval can be measured.It is also possible to directly measure the number of new species that emerge within a particular line, or the number of species that disappear, over a certain time interval.
Draft translation from: Evoluční biologie, 2. vydání (Evolutionary biology, 2nd edition), J. Flegr, Academia Prague 2009.
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