1 8 READINGS IN EVOLUTION, GENETICS, AND EUGENICS 



pleasures and pains, and many of these acquired forms or propensities 

 are transmitted to their posterity." One could ask for no clearer 

 statement of the idea that acquired characters are inherited. 



The fierceness of the struggle for existence was clearly recognized 

 by Dr. Darwin. He considers that this struggle is beneficial to Nature 

 as a whole because it checks the too rapid increase of life. One step 

 farther in the argument, and he would have arrived at the idea of the 

 survival of the fittest, but he never took that step. He agreed with 

 the early Christian fathers in his belief that the powers of development 

 were implanted within the first organisms by the Creator and that 

 subsequent evolution of adaptive characters went on without further- 

 divine intervention. The power of improvement rests within the 

 creature's own organizations and is due to his own efforts. The 

 effects of these efforts, he believes, are transmitted to offspring so 

 that there might be a cumulative effect throughout many generations 

 of the results of effort. 



Erasmus Darwin was perhaps the first to express clearly the ideas 

 that millions of years have been required for the processes of organic 

 evolution and that all life arose from one primordial protoplasmic 

 mass. He writes as follows: 



"From thus meditating upon the minute portion of time in which 

 many of the above changes have been produced, would it be too bold 

 to imagine, in the great length of time since the earth began to exist, 

 perhaps millions of ages before the commencement of the history of 

 mankind, that all warm-blooded animals have arisen from one living 

 filament, which the first great Cause imbued with animality, with the 

 power of acquiring new parts, attended with new propensities, directed 

 by irritations, sensations, volitions, and associations, and thus possess- 

 ing the faculty of continuing to improve by its own inherent activity, 

 and of delivering down these improvements by generation to pos- 

 terity, world without end ? " 



LAMARCK 



Lamarck (1744-182 9), the greatest of French evolutionists, is now 

 looked upon as ''the founder of the complete modern Theory of 

 Descent. " Osborn considers him '' the most prominent figure between 

 Aristotle and Darwin. One cannot compare his Philosophie zoologique 

 with all previous and contemporary contributions to the evolution 

 theory or learn the extraordinary difficulties under which he laboured, 

 and that his work was put forth only a few years after he had turned 



