On general Zoological changes. 13 



Art. II. On the influence of Man in modifying the Zoological fea- 

 tures of the globe ; with statistical accounts respecting a few of 

 the more important species. By W. Weissenborn, D. Ph. 



The history of man does already, in a very appreciable degree', 

 involve the condition of a great many species of the lower ani- 

 mals ; and on account of the strict dependence of all the spe- 

 cies on others, or on the rest of the natural productions, which 

 man likewise modifies, we are perhaps warranted in conclud- 

 ing, that there is no species whose natural relations have not 

 been materially affected by human influence. 



The influence which our species exercises in this respect, 

 is either indirect or direct. The former, which I shall briefly 

 consider first, is a consequence of the change which man 

 brings about in the mineralogical, botanical, or even meteor- 

 ological features, of every part of the globe's surface subjected 

 to his agency. Wherever he makes his appearance, with 

 the exception of such tracts as are, on account of their low 

 temperature or aridity, utterly irreclaimable from their pre- 

 sent barren condition, the surface is gradually modified, as 

 to its constituent principles, state of irrigation, botanical pro- 

 ductions, and the proportion, as well as form, of the vapour 

 dissoh ed in the atmosphere ; whereby, of course, the animal 

 productions of such localities are likewise materially affected. 

 Swamps are drained, forests give way to cultivated fields, and 

 the primitive habitats of animals are thus exchanged with new 

 ones, that owe their origin to man. Plants migrate with him, 

 carrying with them their parasitic insects, or drawing after 

 them other species, that depend chiefly on them for their sub- 

 sistence ; and by these, and other means, he will evidently 

 change the zoological features of every country of which he 

 takes possession. 



Important as this indirect influence of man must appear, 

 even if considered in its mere outline, it is perhaps less great, 

 and at all events less striking, in its immediate effects, than 

 the direct influence which he exercises on the rest of the ani- 

 mals, as to their very existence, or relative numbers in certain 

 localities, or absolute numbers, by destroying or protecting 

 them. 



As a direct agent, man affects the condition of the lower 

 animals, either accidentally or methodically. In the former 

 case, he is but a blind instrument in the hand of the same su- 

 preme power, under whose guidance he unconsciously fulfils 

 his own destinies ; in the latter, he acts as a self-conscious 

 being, in regulating the condition of the lower animals, as he 

 does his own social existence : in the former, nature takes it 

 upon herself to fill the gaps which man makes in her ranks, 



