TROGLODYTES NIGER, THE CHIMPANZEE 557 



as though gi\ing the- tinu' lor thr ijaracic. Thr other animals followed suit 

 bv an cxaggeratc'ci accentuation ol the marching mo\ements. 



Not only chcl these apes show man\ modes ol employing objects which 

 they encountered m their eiuironnu'iU, but some ol them, going a step 

 lurther, manilested a degree ol ingenuity m the construction of implements. 

 Tlu' results of this constructive activity, it must be admitted, were relatively 

 simple. On the other hand, it showed a delmite tendency on the part of the 

 chim])anzec to combine objects m order to deri\e from such combinations 

 an even greater utilitx . Thus.oiu' of themostgiftedof theseanintalsultimately 

 learned to lit a smaller j^iece ol bamboo into a ca\ity ol a larger piece, thus 

 producing lor his special purposes a really long bamboo |)ole which was useful 

 for procuring desired food which had been sus|)t'ndcd above his head out of 

 reach. A similar teiidenc\ to constructi\eness was also observed in certain 

 buildmg propensities ultnnatelx cU'\H'lopt'd b\ these chim|)anzees. W hen the 

 animal cannot reach an ob|ecti\e hung high abo\t' it, it will utilize a box 

 which may In- Wtuncl in the enclosure and thus attempt to decrease the 

 difficulty of space intervening between it and the desired object. There is a 

 possibility also that tht' chimpanzee ma\ pile two (,r more boxes, one on 

 top of another, and thus reach his goal. By adequate e\j)enment it was 

 determined that nearly all the animals eventuall\- developed the ability to 

 construct this sort of tower arrangement in order to climb up and get the 

 banana suspended abo\e their heads. 1 he expert ness, as well as the elliciency 

 with which the chimpanzee learned to perlorm this leat, dillered considerably 

 in different indi\ iduals. The more alert and quickly reacting members of the 

 group accomplished the perlormance lirst. Tlie others were slower, aided no 

 doubt, to some extent, b\ imitation. I lu' (|uicki-r chimpanzees actuall\' j^ut 

 this procedure into operation eiitirelx ol their own initiatne and thus mani- 

 fested a definite constructional idea. Often, having constructed the tower, 

 a long stick was Lised in order to gain a nearer ap]jroach to the suspended 



