FREE BOOKS

Author's List




PREV.   NEXT  
|<   104   105   106   107   108   109   110   111   112   113   114   115   116   117   118   119   120   121   122   123   124   125   126   127   128  
129   130   131   132   133   134   135   136   137   138   139   140   141   142   143   144   145   146   147   148   149   150   151   152   153   >>   >|  
grounds for disbelief in the principle, and also that it lacks experimental proof. * * * * * The explanation of natural evolution given by Darwinism and the principles of Weismann, Mendel, and De Vries, still fails to solve the mystery completely, and appeal has been made to other agencies, even to teleology and to "unknown" and "unknowable" causes as well as to circumstantial factors. A combination of Lamarckian and Darwinian factors has been proposed by Osborn, Baldwin, and Lloyd Morgan, in the theory of organic selection. The theory of orthogenesis propounded by Naegeli and Eimer, now gaining much ground, holds that evolution takes place in direct lines of progressive modification, and is not the result of apparent chance. Of these and similar theories, all we can say is that if they are true, they are not so well substantiated as the ones we have reviewed at greater length. The task of experimental zooelogy is to work more extensively and deeply upon inheritance and variation, combining the methods and results of cellular biology, biometrics, and experimental breeding. We may safely predict that great advances will be made during the next few years in analyzing the method of evolution; and that a few decades hence men will look back to the present time as a period of transition like the era of reawakened interest and renewed investigation that followed the appearance of the "Origin of Species." For the present, we can justly say "that evolution, so far as it is understood, is a real and natural process." V THE PHYSICAL EVOLUTION OF THE HUMAN SPECIES AND OF HUMAN RACES The teachings of science that relate to the origin and history of the human species constitute for us the most important part of the whole doctrine of organic evolution and now, having completely outlined this doctrine as a general one, we are brought to the point where we must deal frankly and squarely with the insistent questions arising on all sides as to the way that mankind is involved in the vast mechanism of nature's order. These questions have been ignored heretofore, in order that the natural history of animals in general might be discussed without any interference on the part of purely human interest and concern. It now becomes our privilege, and our duty as well, to employ and apply the principles we have learned in order to understand more completely the origin of the human body as an organ
PREV.   NEXT  
|<   104   105   106   107   108   109   110   111   112   113   114   115   116   117   118   119   120   121   122   123   124   125   126   127   128  
129   130   131   132   133   134   135   136   137   138   139   140   141   142   143   144   145   146   147   148   149   150   151   152   153   >>   >|  



Top keywords:
evolution
 

completely

 

natural

 
experimental
 

general

 

origin

 

theory

 

organic

 

questions

 

history


factors

 
present
 

principles

 
interest
 
doctrine
 

teachings

 

SPECIES

 

relate

 

science

 

justly


reawakened

 

renewed

 

investigation

 

period

 

transition

 
appearance
 

Origin

 

process

 

PHYSICAL

 

understood


Species

 

species

 
EVOLUTION
 

discussed

 

interference

 

purely

 

animals

 

heretofore

 

concern

 

understand


learned
 
privilege
 

employ

 

nature

 

mechanism

 
brought
 

outlined

 
important
 
mankind
 

involved