SELECTION THEORY WITH OVERLAPPING GENERATIONS

Recent developments in the theory of artificial selection when generations overlap are discussed. The implications of genetic differences between progeny from parents of different ages, and between animals of different ages, for predicting genetic gains and optimizing selection procedures, are pointed out. The importance of proper definition of generation length and genetic selection differential is emphasized. Matrix methods of predicting selection responses are numerically illustrated, and the influence of the initial genetic situation on subsequent gains is shown in an example. Proper specification of an appropriate control population is essential for evaluation of genetic progress. © 1979.