APPLETO'NS' 



POPULAR SCIENCE 



MO:^TTHLY. 



MARCH, 1900. 



THE TKA:^SPLA:NrTATIOi^ OF A KACE. 



By N. S..SHALER, 



DEAN OF THE SCIENTIFIC SCHOOL OF HARVARD UNIVERSITY. 



THE experiments which have been intentionally or accidentally 

 made in transplanting organic species from the countries in 

 which they have been developed to others of diverse soil, climate, 

 and inhabitants are always of much interest to the naturalist — each 

 of them affords indications of some value as to the relations of 

 species to what we term " environment." In almost all instances 

 we find that the transplanted forms undergo changes in conse- 

 quence of the alteration of their circumstances. It is true that 

 certain of our domesticated animals, such as the horse, the dog, 

 and most cattle, follow men from the Arctic to the Antarctic Circle, 

 and that sundry insect pests appear to demand nothing of iSTature 

 save the presence of man; yet, as a whole, the creatures we have 

 turned to use, both plant and animal alike, have shown themselves 

 incapable of accommodating themselves to conditions of tempera- 

 ture differing much from those in which they were developed. 

 With hardly an exception, species or varieties which have been de- 

 veloped in the tropics perish when called on to withstand the winter 

 of higher latitudes. Few, indeed, do well when taken to stations 

 where the heat or the humidity differs greatly from that to which 

 they are accustomed. 



The intolerance of organisms to climatal changes is nowhere 

 more evident than in the varieties, or species, as we would term 

 them, of mankind. It is a well-attested fact that none of the 

 tropical races has ever of its own instance colonized in the tem- 

 perate zones. It is also clear that none of the northern peoples 



TOL. LVI. — 40 



