368 POPULAR SCIENCE MONTHLY. 



Passing over to particulars, it is pertinent to enquire wherein this 

 specific superiority consisted. In what respect was the erect ground- 

 walking human prototype better fitted for advancement than his 

 stoop-shouldered arboreal ancestors? Favorable structural and en- 

 vironmental variations are, generally speaking, along two lines: those 

 that enable animals to escape more easily from their enemies, and those 

 that place them in a better position to acquire sustenance for them- 

 selves. It is impossible to conceive that the pliocene precursor gained 

 any advantage over his ape-like ancestors in the former direction by 

 adopting an upright attitude and abandoning his arboreal abode; for 

 in so doing he lost his earlier and easier means of escape through the 

 trees, without acquiring by way of compensation any corresponding 

 facility for taking flight on foot. The only alternative is, therefore, 

 to suppose that the superiority of the human species was in connection 

 with the food-quest. As far as quantity was concerned there was noth- 

 ing, however, to be gained by coming down from the boughs, for the 

 trees of the tertiary forest afforded a supply of nuts and fruits far in 

 excess of the demand. The advantage must, therefore, have been 

 qualitative, that is to say, in the way of a wider food-choice. As an 

 erect, surface-dwelling creature man was evidently able to secure a 

 greater variety of subsistence than his ape-like ancestors obtained from 

 the trees. Being arboreal their food was confined to nuts and fruits, 

 while by becoming terrestrial he was in a position to add roots and 

 berries, and, in the course of time, also fish and flesh to his fare. Hu- 

 man progress appears, accordingly, to have been away from a strictly 

 frugivorous in the direction of an omnivorous diet. A similar tendency 

 is observable among the other anthropoids. The arboreal apes, for in- 

 stance, are naturally frugivorous, but when taken from the trees and 

 bred in captivity they readily become omnivorous. The semi-terrestrial 

 types exhibit the same proclivities in their wild state. The gorilla, for 

 example, usually lives on fruits, but also eats birds and their eggs, 

 small mammals, reptiles and the like, and has even been observed to 

 devour large animals when found dead. What is only an incipient 

 tendency among the apes probably became an habitual practice with the 

 ancestor of man. The superiority of the human being may thus be said 

 to have consisted in the acquisition of qualities and the occupation of 

 an environment which enabled him to widen the range of his food- 

 choice. 



It is evident enough that the variation of environment was favor- 

 able in this respect, for the terrestrial habitat certainly offered bound- 

 less opportunities for the development of an omnivorous taste ; but it is 

 not so easy to see how the characters we have described as human ren- 

 dered these opportunities available. Berries and roots were plenty in 

 the woods, the streams were alive with fish, and the tertiary forest 



