The Wonderful Ways of Insects and Spiders [ 255 



new tunnels and rooms; and as they dig and bring soil up to the 

 surface of the ground, the "anthill" grows larger. When the soil 

 becomes cold, they close the entrance to the nest and rest quietly 

 in the rooms until the next spring. 



Savage Ant Warriors: Not all ants are as settled in their ways as 

 the cornfield ant. There are some that do not bother to build 

 homes at all: They are almost constantly on the move, wandering 

 from place to place in search of food. Among these nomads are 

 the "driver" ants of Africa and tropical America. They march in 

 close formation, in columns an inch or two wide and sometimes a 

 mile long! Even animals as large as a deer will flee in terror from 

 such an army. 



Many species of ants are savage fighters. Sometimes battles are 

 fought by two colonies of the same species but more often there 

 is a struggle of one species against another. The fighting may 

 occur between two large groups or even between individuals. 



If you stop to watch a lively group of ants on the ground or 

 sidewalk, you may find it is divided into two factions struggling 

 over a bit of food or you may not even discover the cause of the 

 conflict. I have heard of a sidewalk ant battle that raged for more 

 than five hours, until each colony was reduced to a few battered 

 members. 



You may wonder how the ants in such a struggle know friend 

 from foe. Members of different colonies look exactly alike, yet 

 you see individuals meet and at once pass on to another warrior 

 or start fighting. Apparently an ant's antennae help it distinguish 

 its own team mates from the opposition for as two fighters meet, 

 the antennae of each touch the head of the other. There is also a 

 theory that ants have a characteristic odor that varies with each 

 colony and may thus be an aid to solving the "friend-or-foe" 

 puzzle. 



Ant Hangers-on: As you observe some ant colonies you may be 

 puzzled by the presence of other insects that act as though they 

 belong there. If you were able to study ant nests all over the 

 world, you would find there are actually several thousand differ- 

 <ent kinds of insects that make their home with ants. Some of 



