No anthropologist has ever found a barter economy
The story every economics textbook tells about the origin of money has one small problem: nobody can find it happening.
Adam Smith's version, still taught as a kind of creation myth, goes like this: before money, people bartered directly, my chickens for your cow, and barter was so inconvenient that societies eventually converged on a universal medium of exchange. Tidy, intuitive, and, as far as anyone can tell, never actually observed. Anthropologists have searched for a community anywhere in the world where everyday life ran on this kind of spot-trade barter, and the honest conclusion, per Cambridge's Caroline Humphrey, is that no example has ever been documented.
The late anthropologist David Graeber built Debt: The First 5,000 Years on the wreckage of that myth. His case: the earliest records we have of exchange, from Mesopotamia onward, aren't barter at all, they're credit. People kept running tabs, denominated in units of silver that often didn't even physically exist as coins yet, settled periodically within tight-knit communities that already trusted each other. Barter, when it does show up historically, tends to appear between strangers who don't have that trust, after money already exists, not before it.
Which flips the usual story on its head: money wasn't invented to escape barter's awkwardness. Debt came first, and money was one of the things people built to keep track of it.