484 SOCIAL LIFE OF ANIMALS 



tion. Some biologists are disposed to regard the higher organisms 

 as colonies of lower forms. 



Communities. — (i) Bees have a queen (reproductive), the male 

 drones (reproductive) and the workers which are only short-lived 

 laborers. The chosen queen is fed " bee bread." (See Sex Deter- 

 mination, page 533.) (2) Termites or " White ants." The workers 

 are small, blind, wingless, pale in color and sexually immature but 

 with strong jaws. The " soldiers " are blind, wingless, immature but 

 have highly developed scissors-shaped jaws and an enlarged head, 

 both heavily chitinized and darker in color than the rest of the body. 

 The complemental females and males are blind, wingless, and not 

 completely mature, but may develop to supplement in the produc- 

 tion of young if the true sexed individuals are not sufficient. The 

 true or chief females and males are darker in color than the other 

 castes, winged and with well-developed visual organs. They live 

 above ground; the others are either subterranean or with covered 

 tunnels. (3) True ants consist of winged males Q.nd females, workers 

 and soldiers. We find that there is a social evolution in ants as in 

 man. (Wheeler.) Foraging or maraudifig ants, like Ecitor, have 

 officers and scouts. Slave-holding ants, like Polygerus, have become 

 unable to dig, care for their young, or store up food without slaves. 

 The herding ants live in beneficial association, keeping aphids for 

 their milk, " honey dew." The harvester ants store up grains and 

 seeds. The thief ants {Solenopsis molestd) feed on the larvae and 

 pupae of larger ants, escaping into burrows too small for the avengers 

 to follow. The commensal ants include Leptothorax emersoni which 

 secure food and shelter from Myt-micae brevinoides and in return 

 act as barbers and manicures, probably removing parasites and 

 keeping their benefactors more healthy. (Wheeler.) 



Gregariousness. — Herds of buffalo, packs of wolves and schools 

 of whales collect for protection and food. In sheep, a leader or 

 sentinel is characteristic of such groups. The same is true in many 

 other animals. Pallas states that the saiga antelopes of Siberia 

 change sentinels. In the •#nd reindeer, females act as sentinels and 

 are also said to change places when wearied by standing. 



When cattle or even sheep are attacked in the wilds, they form 

 a circle with the males and the most powerful females directing their 

 horns outward, while weaker females and the young are huddled in 

 the center, Man is sometimes less concerned for the welfare of his 

 own. 



