EVOLUTION AND DISTRIBUTION OF ANIMALS. 317 



it is with, the other animals and with a large proportion of the 

 plants. . . . The naturalist, looking at the inhabitants of these 

 volcanic islands in the Pacific, feels that he is standing on Ameri- 

 can land." 



The question, then, is this : If these species have been created 

 as we find them on the Galapagos, why is it that they should all 

 be very similar in type to other animals, living under wholly dif- 

 ferent conditions, but on a coast not so very far away ? And 

 again, why are the animals and plants of another cluster of vol- 

 canic islands — the Cape "Verde Islands — similarly related to those 

 of the neighboring coast of Africa, and wholly unlike those of the 

 Galapagos ? If the animals were created to match their condi- 

 tions of life, then those of the Galapagos should be like those of 

 Cape Verde, the two archipelagoes being extremely alike in re- 

 spect to soil, climate, and physical surroundings. If the species 

 on the islands are products of separate acts . of creation, what is 

 there in the nearness of the coasts of Africa or Peru to influence 

 the act of creation so as to cause the island species to be, as it 

 were, echoes of those on shore ? 



If, on the other hand, we should adopt the obvious suggestion 

 that both these clusters of islands have been colonized by immi- 

 grants from the mainland, the fact of uniformity of type is ac- 

 counted for, but what of the difference of species ? If the change 

 of conditions from continent to island may on the island cause 

 such great and permanent changes as to form new species from 

 the old, why may not like changes take place on the mainlands 

 as well as on the islands ? And if possible on the mainland of 

 South America, what evidence have we that species are perma- 

 nent anywhere ? May they not be constantly changing ? May 

 not what we now consider as distinct species be only the present 

 phase in the changing history of the series of forms which consti- 

 tutes the species ? 



The study of these and many similar facts can lead to but one 

 conclusion : 



These volcanic islands rose from the sea destitute of land life. 

 They were settled by the waifs of wind and of storm, birds and 

 insects blown from the shore by trade winds, lizards carried on 

 drift-logs and floating vegetation. Of these waifs few came per- 

 haps in any one year, and few perhaps of those who came made 

 the islands a home ; yet, as the centuries passed on, suitable inhab- 

 itants were found. That this is not fancy we know, for we have 

 the knowledge of many similar transfers. Every one who has 

 approached our eastern shores by sea in the face of a storm will 

 realize this. Hosts of land birds — sparrows, warblers, chickadees, 

 and even woodpeckers — are carried out by the wind, a few fall- 

 ing exhausted on the decks of ships, a few others falling on 



