426 



POPULATIONS 



The nasute soldier (Figs. 148, 149), 

 characteristic of a number of genera in the 

 sub-family Nasutitermitinae, has reduced 

 mandibles and a prolonged frontal portion 

 of the head with the glandular opening at 

 its tip. The frontal gland in the head se- 

 cretes a viscid and chemically irritating 



that are attached by silken threads spun 

 from the mouths of the larvae. Some 

 workers hold the leaves together while 

 other workers bring the larvae to the edges 

 of the leaves, where they are moved back 

 and forth as they spin the silk that attaches 

 the leaves firmly together. By the recipro- 



\\ 





- ^ 



k . jr j,.^ fc*^ ,^1, V V "° - s "^ 











Fig. 149. Nasute soldiers of tlae termite, Nasutitermes ephratae, standing guard at a break in 

 the surface of their nest. Heads of workers repairing the break can be seen at the edge of the 

 hole at the middle right and upper right. (Photograph by Ralph Buchsbaum.) 



fluid that is forcibly shot out of the "squirt- 

 gun" for a distance of half an inch. The 

 nasute soldier e£Fectively defends the col- 

 ony against such enemies as ants. 



DIVISION OF LABOR AND ONTOGENY 



Rosch (1930) reports a temporal divi- 

 sion of labor in the hfe of an individual 

 honeybee worker. This sequence of activi- 

 ties, roughly outlined in Table 29, is indic- 

 ative of an order often to be found, but 

 should not be construed rigidly. Rosch says 

 that the division of labor is flexible with- 

 out any hard and fast time schedule. 

 Young field bees may return to nursing 

 functions if there is a need. 



An example of a social function at differ- 

 ent stages in the life cycle is found in the 

 Old World genus of ants, CEcophylla. The 

 nests of these ants are constructed of leaves 



cal action of the workers and larvae, an ar- 

 boreal nest is constructed. 



MECHANISMS OF SOCIAL 

 INTEGRATION 



Division of labor and integration are as- 

 sociated principles. Integration has no 

 function unless there are differentiated 

 parts that must act in relation to the whole. 

 Specialization of function cannot occur un- 

 less the specialized parts are coordinated. 

 EflBcient homeostasis follows an increase in 

 the special functions of integrated parts. 

 These principles apply to every organismic 

 level (p. 683) from the cell to the ecosy- 

 stem, but are particularly well exhibited by 

 the population of a colony of social insects. 



These facts afford proof of the unity of 

 the population (p. 389). Of course, at this 

 stage of our knowledge we are far from 



