The ancient world had many independent city states: Uruk, Thebes, Tyre, Rome, Athens, and Tenochtitlan. Some of these cities expanded into powerful empires. Today the world has only three city states: Monaco, Singapore, and the Vatican City. Of the three, Singapore has become a global center of economic activity.
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Attacus atlas - The atlas moth, named for the wing pattern resembling an atlas, holds the record for having the largest total wing surface of any moth; almost 400 square centimeters. The atlas moth does not eat during its adult stage; it does not have a mouth. It survives from the fat reserves accumulated during the larva stage. The adult stage of the atlas moth is dedicated to breeding a new generation. Females secrete a pheromone during the mating season; males can detect this chemical scent through their long feathery antennae.
