An Evolutionary Biologist Explains Why We Speak
Geege Schuman stashed this
Humans are the only species that trade.
Sometime around 120,000 years ago in the desert near Oued Djebbana, in what is modern-day northern Algeria, a human acquired some small seashells. The shells were from a species known as Nassarius (Plicarcularia) gibbosulus, a grape-sized marine gastropod (like a garden snail) that lives in the shallow waters of the Mediterranean Sea, and they were perforated and made into beads, probably for a necklace.
If evidence of what anthropologists call symbolic behavior—the use of seashells for decorative and aesthetic purposes—as far back as 120,000 years ago isn’t striking enough on its own, Oued Djebanna’s location should be: It lies about 120 miles inland from the sea.
Our species arose in Africa about 160,000 to 200,000 years ago. Tens of thousands of years later, when that person acquired those seashells, all human groups were living as hunter-gatherers with only the most primitive of tool technologies and shelters. Farming would not be invented for another 110,000 years, and metalworking and writing not for another 5,000 or so after that. There were no roads, and no markets to buy things from.
And yet, at Oued Djebanna and at several other ancient sites around the Mediterranean, there is evidence that humans were engaged in economic activity. From our very earliest times, our ancestors were engaging in trade. The shells must have been carried inland and changed hands repeatedly, swapped over and over for other things of value.
Today this kind of behavior is taken for granted, and the commerce it generates is the basis of the world’s economy. But humans’ economic transactions, such as those at Oued Djebanna, go beyond every other species’: No other animal does it. Even in our extinct and big-brained cousins the Neanderthals, who were alive at the same time as these bead-trading humans of Algeria, there is no compelling evidence of symbolic behavior or trade apart from a few scattered instances of flower petals in shallow graves.
The reason might be that even the simplest of exchanges requires a sophisticated set of rules and understandings: How can I trust you to give me something of equal value for my shells? How do I know you won’t steal my goods and just run off? And how do we ever agree in the first place on the worth of our respective items?
This last question is in some ways the most important because the answer might just explain another enigma about humans: our possession of language. Just as we are the only species to have complex systems of trade and exchange, we are also the only species that has language, and it might just have its origins in our earliest economic behaviors.