10 GENETICS AND EUGENICS 



1831, to October 2, 1836. Much time was spent by this 

 expedition in making surveys of southern South America, 

 ana of oceanic islands. For a large part of this time Darwin 

 was brought into intimate daily contact with the animals 

 and plants of an unexplored part of the world. What a post- 

 graduate course in natural history this was! It is probably 

 fortunate that his previous studies of natural history had not 

 been more specialized and detailed, and that he had no master 

 at hand to guide him in his studies during the voyage. Other- 

 wise he would certainly have been hampered by precon- 

 ceived ideas and have been less inclined to depart from ac- 

 cepted notions. But here he was face to face with a new world 

 of animals and plants awaiting explanation, and his it was to 

 study them without assistance or let up for three years. For 

 an ordinary boy of twenty-two, what a perplexing and be- 

 wildering task, what a fate, sentenced to five years of sea- 

 sickness, the effects of which were to last throughout his life! 

 But for a Darwin, what an opportunity, to study at first hand 

 the animals, the plants, the peoples of all lands and of all 

 seas! 



After Darwin had spent some three years on the Beagle he 

 returned home with impaired health which forced him to live 

 quietly at his country home in Downs, England. Here he 

 devoted a part of each day to working up the scientific results 

 of his journey, and published during the next twenty years an 

 attempt to correlate, to unify and to explain the various ob- 

 servations which he had made, an attempt which finally 

 found fruition in his theory of evolution through natural 

 selection. 



It had long been known to a number of Darwin's scientific 

 friends that he was working on a theory of evolution when, 

 in 1858, he received from A. R. Wallace, then in the East 

 Indies, the manuscript of a paper containing precisely the 

 same explanation of organic adaptations which he himself 

 had reached. Darwin was naturally much embarrassed, but 

 seemed willing to throw aside his own work and give prece- 

 dence to Wallace's paper. On the advice of friends, however. 



