Insects and their world 



as in the wasps or the bumblebees, she lays eggs that hatch into workers, 

 and form the nucleus of a new colony. 



Most ants do Httle nest building, and do not make combs, but hve 

 in a labyrinth of communicating galleries in the soil, as we find when we 

 try to destroy a nest underneath a brick path. Instead of providing each 

 egg with a cell in which it can grow up as larva, and then as pupa, ants 

 keep the eggs, larvae and pupae separately, and often move them about. 

 If you break open an ant's nest you will see the workers seize all the 

 immature insects in the damaged parts and carry them quickly away. 



Queen ants have wings only for the brief nuptial flight. The workers, 

 which again are sterile females, do all their foraging on foot, running 

 quickly about, and touching things with their long antennae. The 

 antennae have a bend in the middle, Hke an elbow, and this is one of the 

 distinguishing marks of an ant. If you watch one running along it 

 continually waves its antennae, and often taps them against the ground, 

 or against stones and sticks in its path : or if it does not actually touch 

 objects it 'explores' them by bringing its antennae near. It is using its 

 highly developed sense of smell, which we have seen in Chapter IV 

 operates through sense organs in the antennae and the legs. 



The senses of ants are very highly developed. It has been shown that 

 as they go off on a foraging trip they keep track of their direction from 

 the nest by noting the direction of the sun, or if the sun is not visible, 

 they use the polarised Hght that comes from the sky. This is the so- 

 called 'light-compass' reaction, which we have mentioned before, and 

 which we shall come to again at the end of the chapter. 



After a single ant has found food and returned to the nest the other 

 workers follow the same route. It is annoying to find one of these ant- 

 trails leading under the back door and into the larder, but the behaviour 

 of the ants is fascinating to watch. The trail usually keeps along the 

 bottom of the walls, and winds round corner after corner, till it finally 

 leads up on to the shelf or table where the food is to be found. Ants 

 scurry along it in both directions, following the scent left by the others. 

 If you draw your finger across the trail the ants are baffled for a time, 

 and stop in a bewildered way when they come to the invisible barrier 

 of a strange scent : then some individuals find their way across or round 

 the patch, and set up a new scent trail for the others to follow. 



If social Ufe in insects is measured by the extent to which individuals 

 depend on each other, and exchange food material among themselves, 

 then ants have the highest level of all. All kinds of food, animal and 

 vegetable, are acceptable to them — another reason why they are at once 

 so successful as insects and so troublesome to man. The workers give 

 the larvae food, partly masticated and predigested : the larvae produce 



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