THE 



AMERICAN NATURALIST 



Vol. LI. February, 1917 No. 602 



THE SELECTION PROBLEM^ 

 RAYMOND PEARL 



Of all the supporters of the doctrine of natural selec- 

 tion as the chief factor in organic evolution, August 

 Weismann was preeminent. He stood shoulder to 

 shoulder with Wallace in his entire willingness to attempt 

 the explanation by selection of any biological phenom- 

 enon whatsoever, and he far outstripped the latter in the 

 keenness and subtlety of his logical powers when an espe- 

 cially difficult bit of exegetic activity was called for. 

 Both, it hardly needs saying, left Darwin far behind in 

 the extent of their advocacy of the AllmacJit of selection. 

 Certain it is that if any one could speak authoritatively, 

 and without suspicion of either hostility or doubt, about 

 the selection theor}% Weismann could. For that reason 

 it seems desirable to take as the starting point of this dis- 

 cussion a statement made by that distinguished biologist 

 so lately as seven years ago. At the Darwin Centenary 

 meeting in Caml)ri(lgo. Weisiiiniin, discussing the ade- 

 quacy of the selection theory to explain the initial steps 

 of evolutionary change, saidr 



To this question even one who, like myself, has been for many years a 

 convinced adherent of the theory of selection, can only reply: "We 



1 Papers from the Biological Laboratory of the Maine Agricultural Ex- 

 periment Station No, 109. This paper constitutes the address of the retir- 

 ing President, read in abbreviated form at the dinner of the American So- 

 ciety of Naturalists in New York, December 29, 1916. 



2 "Darwin and Modern Science," Cambridge, 1909, p. 25, The italics are 

 in the original. 



