P M 



P M 



Father 







Mother 



SOME 



oftKe 



GERM 



CELLS 



SOME 



of the 



OFFSPRING 



Figure 59. Diagram to illustrate the redistribution of genes in re- 

 production. In each of the two parents are two strings of genes, 

 paternal (P), and maternal (M), represented respectively in black 

 and white. To the germ cells the paternal and maternal genes of the 

 parent are distributed in all possible different combinations, as indi- 

 cated by combinations in the sample germ cells from each parent. Any 

 two of the germ cell combinations may be put together to produce 

 zygotes, as illustrated by three sample offspring. The number of 

 diverse germ cell and zygote combinations producible is thus very 

 great. 



285 



