ZOOLOGY 459 



the confines of my subject. But if the student of lower forms should 

 find well-defined principles of biological association and principles of 

 animal conduct, it is not only his privilege, it is in a sense his duty 

 as well to bring these to the consideration of the students of human 

 social and ethical relations. Unless in these matters there has been a 

 break in the continuity of evolution, the simpler relations to be observed 

 in lower animals must surely possess a profound interest — and perhaps 

 more. 



In a true sense, any of the many-celled animals is a community, 

 whose constituent members are the differentiated tissue-cells, which 

 have undertaken the various tasks of digestion, contraction, sensation 

 and the rest. By far the majority of animals are cell-communities of 

 this nature. Considering these as individuals, though of a secondary 

 order, we find some communities made up of several animals which 

 have banded together for mutual support and defense, giving us as 

 in the wolf -pack a counterpart of the lowest associations of savage men. 

 But among insects especially we find colonies of numerous multicellular 

 individuals which may be so rigidly specialized for the performance of 

 certain tasks that we can not avoid the use of terms applied to civilized 

 human groups in describing their differentiation and division of labor. 

 Some colonies of bees comprise queens and drones and only one kind 

 of sterile workers, though when newly hatched these last serve as guards 

 and nurses, taking the field as foragers for pollen and honey only later 

 in life. In various ant-colonies we shall find workers who serve as 

 herdsmen, devoting their time to the care of the ant-cattle or aphids; 

 again there are masons, and gardeners, and carpenters, and soldiers of 

 various ranks, while in the honey-ant some individuals may serve as 

 living receptacles for the tribal stores of food. Each kind undertakes 

 one of the tasks that are vital for the life of the community as a whole. 

 Instinctive and unreasoned their activities may be, and undoubtedly 

 are, but the economic and social relations of the component members 

 of the colony are strikingly analogous to certain fundamental phe- 

 nomena of human societies. But still more wonderful are the cases 

 that may be found among hornets and wasps. A fertile female over- 

 winters and places her first-laid eggs in the chambers of a simple nest 

 that she constructs herself. When the young of the first brood hatch, 

 she provides them with food, enlarges the nest, and continues the task 

 of egg-laying, while her first offspring relieve her of her former duties 

 as they become able. They enlarge the nest, they care for their younger 

 kin as they hatch, they forage abroad for the food-supplies for the 

 colony. And so the community that begins life in the early spring 

 with a solitary animal advances during the passing weeks to a degree 

 of complexity that is truly astounding. As an epitome of insect social 

 evolution it gives in a few weeks a review of the process that in other 



