LECTURE VI. 



INSTINCT FOR COMMUNITIES OF ANIMALS. — ITS 

 RELATION TO THE DOCTRINE OF NATURAL SE- 

 LECTION. 



Illustrations of the Community System.— TJu Cow-bird.— Three kinds 

 belonging to the same species. — Necessity for slaves among Ants. — 

 The brood or annual flock. — Permanent organization. — Leaders. — 

 Sentinels.— Pelicans of Utah Lake.— The Beaver.— Morgan' s 

 Work.— The Rank of the Beaver.— The Muskrat.— Variation of 

 Instinct necessary. — Complexity of work no proof of Intelligence . — 

 Consideration of theories. — Accumulated work of Intelligence. — In- 

 stinct like it, in effect. — The Homy-bee. — Bumble-bees and Wasps. — 

 Slave- Ants. — Darwin's Explanation. — Difficulties. — Natural Se- 

 lection and Variation not sufficient. — Wallace on Natural Selec- 

 tion applied to man. 



In almost every manifestation of Instinct thus far 

 introduced, the act has been one for the preserva- 

 tion of the individual or species, but such as the in- 

 dividual could perform for itself. A single pair at 

 most, caring for their young, in all their instinctive 

 acts would represent not only so many individuals 

 but the species as a whole. 



We began, however, to see the introduction of 

 another principle, when we found adults uniting in 

 action to aid each other ; one species of birds even 

 calling to their aid others, of different species, against 

 a common enemy. And when we found a system 

 of instinctive acts, by which alarm-notes are sounded 



