THE PROBLEM OP INBREEDING 137 



the sire's side of the pedigree, reappeared in the 

 second ancestral generation on the dam's side. 

 What this clearly means is that at least one half 

 of all the dam's ancestors, in the third and higher 

 ancestral generations, are identically the same 

 animals as are ancestors of the sire. The next 



100 



80 



60 



20 



2 4 6 8 10 12 14 



Generations 



Pio. 2. — Diagram showing (a) the total inbreeding (heavy solid 

 line) and (6) the relationship (heavy broken line) curves for the 

 Jersey Bull, King Melia Rioter 14th. The high order of the inbreed- 

 ing and relationship between the sire and dam in this case is evident 

 by comparison with the lighter lines, which give the maximum values 

 for continued brother X sister and parent X offspring breeding. 



entry in Table 7 indicates that in the fourth and 

 higher ancestral generations at least f of all the 

 dam's ancestors were the same individual animals 

 as were also ancestors of the sire. One half of 

 them were the same before the reappearance of 



