Ants, acacias and shameless bribery

AESOP’S FABLES are supposed to illustrate a moral point. If he had lived in Central America rather than Greece, though, he might have thrown in the towel at writing one entitled “The Ant and the Acacia Tree”. For, as Sabrina Amador-Vargas and Finote Gijsman of the Smithsonian Tropical Research Institute, in Panama, have discovered, the moral of this particular tale is that laziness pays.Acacias are a widespread group, but one member in particular, , is famous for its symbiotic relationship with ants. The ants attack herbivorous insects which eat the tree’s leaves, remove encroaching vegetation, and also protect it from disease by distributing antibiotics synthesised by bacteria living on their legs. In return, the tree rewards ants with food in the form of protein-rich Beltian bodies (the white objects in the picture above) and sugar-rich nectaries, and with secure housing inside hollow thorns that have evolved specifically for the purpose.