CHAP. VII The Industries of Animals 119 



are often utilised, the weak combine against the strong, 

 and the victims of even the strong carnivores often show 

 fight valiantly. 



2. Shepherding. — Although the ants are the only animals 

 which show a pastoral habit in any perfection, and that 

 only in four or five species (e.g. Lasius niger and Lasius 

 brunneus), I think that the fact is one about which we 

 may profitably exercise our minds. I shall follow Espinas's 

 admirable discussion of the subject. 



We may begin with the simple association of ants and 

 aphides as commensals eating at the same bountiful table. 

 But as ants discovered that the aphides were overflowing 

 with sweetness, they formed the habit of licking them, the 

 aphides submitting with passive enjoyment. Moreover, as 

 the ants nesting near the foot of a tree covered with 

 aphides would resent that others should invade their pre- 

 serves, it is not surprising to find that they should continue 

 their earthen tunnels up the stem and branches, and should 

 eventually build an aerial stable for some of their cattle. 

 Thither also they transport some of their own larvas to be 

 sunned, and as they carried these back again when the 

 rain fell, they would surely not require the assistance of an 

 abstract idea to prompt them to take some aphides also 

 downstairs. Or perhaps it is enough to suppose that the 

 aphides, by no means objecting to the ants' . attentions, 

 did not require any coaxing to descend the tunnels, and 

 eventually to live in the cellars of the nests, where they 

 feed comfortably on roots, and are sheltered from the bad 

 weather of autumn. In autumn the aphides lay eggs in 

 the cellars to which they have been brought by force or 

 coaxing or otherwise, and these eggs the ants take care of, 

 putting them in safe cradles, licking them as tenderly as 

 they do those of their own kind. Thus the domestication 

 of aphides by ants is completed. 



Now what is the theory of this shepherding ? (i) We 

 have no warrant for saying that the ants have deliberately 

 domesticated these ' aphides, as men have occasionally 

 added to the number of their domesticated animals. It 

 does not seem to me probable that even primitive man 



