72 THE LAMARCKIAN DOCTRINE 



did much in the course of generations to bring about co-adaptation 

 and correlation. Thus Herbert Spencer maintained that without 

 the transmission of use-acquirements the evolution of the higher 

 animals would have been impossible. He instanced the weighty 

 horns of the elk, pointing out that their usefulness to the individual 

 depended on the co-adaptation of a thousand parts in head, neck, 

 trunk, and limbs, and insisted that, since it is unlikely that all of 

 them can ever have varied favourably together in any individual 

 and practically impossible that they can have so varied in a 

 succession of individuals, their co-adaptation was explainable only 

 on the hypothesis that acquirements tend to become inborn. 

 Obviously, his reasoning was founded, first on a belief that all 

 characters grow under the stimulus of use, and second on an 

 insufficient appreciation of the magnitude of use-acquirements, 

 which, as in other cases, brought about co-adaptation between the 

 horns of the elk and the structures associated with them. 



1 14. More recently some biologists, more particularly Professors 

 Lloyd Morgan, Osborn, and Mark Baldwin, while admitting that 

 use-acquirements are, in all probability, not transmissible, have 

 argued that their presence, by acting as a screen behind which 

 progression could occur, may conduce indirectly to evolution of a 

 kind which closely mimics that which would result from the inherit- 

 ance of them. Thus suppose drowning were a stringent selective 

 cause of human elimination, then those individuals who learned 

 to swim quickest and best would survive in the greatest numbers. 

 If any of their offspring varied in such a way that they were able, 

 in some measure, to swim ' naturally ' (i.e. without learning), they 

 would be at an advantage, and would survive in larger numbers 

 than contemporaries who had more to learn. In this way a human 

 race that, like many lower animals, could swim instinctively, would 

 ultimately be established. In other words, without any inheritance 

 of acquirements, characters, which in the ancestors developed 

 under the influence of use, would in the descendants develop 

 under the influence of nutriment. But the evidence that this view, 

 which has not been tested by an appeal to reality, though the test is 

 possible, is mistaken is overwhelming. Characters developed under 

 the influence of use are, as we see, very much more adaptive than 

 those developed under the stimulus of nutriment. Therefore, 

 though there is unlimited evidence of the former replacing the 

 latter, there is none to the contrary. Thus the helplessness, the 

 immaturity of the human being, before he has made his use- 

 acquirements, demonstrates to what an extent the power of 



