Social Transmission and Instinct 67 



III. These positions are illustrated in a very fortunate 

 way by the interesting cases reported by Professor LI. Mor- 

 gan in his instructive discussion. He cites the beautiful 

 observation that his young chicks had the instinct to 

 drink by throwing their heads up in the air, etc., but that 

 it came into action only after they had the taste ^ of water 

 by accident or by imitating the old fowl. As LI, Morgan 

 says, the 'incidence of natural selection' is prevented by 

 imitation or instruction or intelligent adaptation (in cases 

 where experience is required). So, in this instance, 

 the instinct of drinking, which only goes so far as a 

 connection of certain muscular coordinations with the 

 sense of taste (wet bill) is made effective for the life inter- 

 ests of the chick. Thus kept alive the species has plenty of 

 time — in case it shotdd be necessary — to get a connection 

 established also between the sight centre and the same 

 coordination of movements ; so that future chicks may be 

 born with a capacity for drinking when water is seen only, 

 without waiting for instruction, a fortunate accident, or an 

 example to imitate. So we may imagine creatures, whose 

 hands were used for holding on with the thumb and 

 fingers on the same side of the object held, to have first 

 discovered, under stress of circumstances and with varia- 

 tions which permitted the further adaptation, how to make 

 intelligent use of the thumb for grasping opposite to the 

 fingers, as we now do. Then, let us suppose that this 

 proved of such utility that all the young that did not do it 

 were killed off; the next generation following would be 

 intelligent or imitative enough to do it also. They would 



1 Or other form of stimulation from getting the bill wet (this in view of a 

 later discussion, as to just what the stimulation is, in Science) — reprinted by 

 Mills in Nature and Development of Animal Intelligence, pp. 277 ff. 



