WHY WE MUST BE EVOLUTIONISTS 



nobler forms of life. Among back-boned animals the first 

 were the fishes. These led to the amphibians, and these were 

 succeeded by reptiles. Later there arose birds and mammals. 

 Throughout the ages, life has been slowly creeping upward. 

 Detailed pedigrees are disclosed in the rocks, some of them 

 with marvellous perfection, as in the evolution of horses 

 and elephants, camels and crocodiles. For some animals, 

 such as fresh-water snails and marine cuttlefishes, there is 

 an almost perfect succession of fossils, forming a chain in 

 which link 10 is very different from link 1, yet just a little 

 different from link 9, as link 2 is a little different from link 1. 

 For such animals we can almost see evolution anciently 

 at work! 



The geographical evidences are also endless. If the pres- 

 ent state of affairs is not the outcome of a natural process 

 of evolution, why should the fauna of oceanic islands be 

 restricted to those animals which can be accounted for by 

 transport over the sea by currents and by winds, or on the 

 feet of birds? Thus there are no amphibians on oceanic 

 islands, because few amphibians can endure salt water. 



The inhospitable Galapagos Islands are said to be the 

 submerged tops of cold volcanoes, which belong to an 

 ancient peninsula that became first an island and then an 

 archipelago. They have a peculiar fauna, which includes 

 the famous giant tortoises. There are ten different kinds 

 of giant tortoise on ten different islands, and those that are 

 on the islands that are farthest apart are most unlike. There 

 are five different kinds in different parts of the largest island, 

 which is called Albemarle. Now if we consider thought- 

 fully these facts what can we find them to mean except that 

 isolated groups of one ancient stock of the original peninsula 

 have varied slightly on one or another island and that the 

 isolation prevented any pooling or blending of the new 



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