THE ANTS OR PISMIRES 



the nectar makes flowers attractive to bees. The ant thus acts 

 as an agent in seed-dispersal. Whether or not this is true, it 

 seems that ants do play some part in spreading plants such as 

 gorse which have heavy, edible seeds. In this example, the 

 ants eat only part of the seed; the seed consequently remains 

 capable of germination. 



The true harvesting ants live mainly on seeds, especially 

 of grasses. Their behaviour has an extraordinary analogy 

 with that of the honey-pot ants, for they store the seeds in 

 underground chambers and use them as a source of food 

 during periods of drought. Tracks leading to the nest often 

 look like well-marked roads, since many species of these ants 

 forage in large companies. Usually the seeds are brought in 

 enclosed in the chaff, and this is removed inside the nest 

 and brought out again and thrown on a rubbish heap 

 which forms a sort of ring round the nest. In some species 

 the nest may be a large mound, sometimes as much as 20-30 

 feet across and penetrating 6 feet or more into the soil. The 

 entrance may be large and lie in a crater made up of coarse 

 soil pellets. 



It is well established, and was indeed known to the ancient 

 Romans, that if the seeds get damp in their underground 

 chamber, the ants bring them out and spread them in the sun 

 to dry. Later they carry them in again. They may also bite 

 off the part of the seed called the radicle to prevent them from 

 germinating. In spite of these measures their stores do some- 

 times germinate; they are then thrown away on the rubbish 

 heap. This gave rise to a story that the ants planted seeds to 

 produce a crop near the nest for. the following year. Al- 

 though it is true that rejected seeds often germinate and grow 

 in the rubbish heap, and that the crop of seeds thus produced 

 may be harvested, there is no reason to suppose that this is 

 anything more than an accident. Many of the harvesting ants 



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