A Byzantine general of “ignoble descent” oversaw the building of Petra, on the Colchian coast, and set up an import monopoly. “They are robbing us of all our gold as well as of the necessities of life, using the fair name of trade,” locals complained, according to Procopius. “There has been set over us as ruler a huckster who has made our destitution a kind of business.”

A growing market for ejiao—a gelatin made from donkey hide believed by practitioners of traditional Chinese medicine to increase libido and slow aging—has led to a global trade of millions of donkey skins each year. Asses are often kidnapped from rural African villages, where their labor is valued highly, then taken to markets and slaughtered for export. “The donkeys,” said a sanctuary manager while visiting a market in Tanzania, “are very stressed.”

For Kid Nation, a reality show that aired in 2007, forty children went to stay in a New Mexico ghost town for forty days. They lived as laborers, cooks, merchants, or an upper class; many worked fourteen-hour days to earn buffalo nickels to spend on root beer. In the final episode, some participants raided the dry goods store. “It’s free,” said one kid, his mouth stuffed with gummy bears. Another raider was heard announcing, “There is a god.”

Herodotus reports that after Cyrus the Great was warned by a Spartan herald not to tread further into Greek lands, the Persian king received a primer on Sparta, including an explanation of an agora, to inform his response. “I have never yet been afraid of any men,” he told the herald, “who have a set place in the middle of their city where they come together to cheat each other.”

The head female of a paper-wasp nest allows others to occupy space in her home—so long as they help raise her offspring. The labor market is, however, elastic: if other nests nearby have childcare needs, she maintains a lower work requirement from her “helper” wasps.