Anthropologist Jennifer Perry has her bladder to thank for one of her favorite recent discoveries. Perry, a professor at the California State University–Channel Islands, was conducting an archaeological survey of Santa Barbara Island, a square-mile speck off the California coast that takes about three hours to get to, by boat. There are few buildings of any kind on Santa Barbara Island, and no fresh water. When Perry had to go to the bathroom, she simply found a clear spot away from her colleagues and crouched, looking out of a dig site she and her team had just finished cataloging. As it turned out, the position gave her a new vantage point over the dig, which let her spot something they had overlooked. "Especially for women—I don't mean to be gross, but you're seeing the ground really close. It's a different angle there," she says. That’s when she saw it: "Something shimmered at me."
It was a small, flat-bottomed, soapstone cup, the likes of which the team had never seen before, in part because Santa Barbara and its fellow Channel Islands have been subject to a century and a half of looting. The cup is one of hundreds of new objects Perry and her team found during their survey, which suggests Santa Barbara Island was much more important to ancient people than previously thought—and shows the people inhabiting the island might have figured out an innovative way of dealing with water scarcity, a problem that's still at the top of Californians' minds.
California's Channel Islands are a series of rugged mountaintops thrust up out of the ocean along 150 miles of the state's coastline. The archipelago has long been recognized as a rich spot for human prehistory. One of the oldest sets of human remains ever found in the Americas—the Arlington Springs Man—was discovered on Santa Rosa Island. It's thought that people first paddled to the islands 13,000 years ago, at which time four of the northern islands were one landmass and pygmy woolly mammoths may have roamed its peaks.
But little Santa Barbara Island has always been a bit of a footnote. After studying the island in the 1960s and '70s, archaeologists concluded that prehistoric people used it only as a stopover, a spot to dock and plan during expeditions to hunt sea lions and seals. The people are thought to be ancestors of the Gabrieleño tribes that live throughout Southern California today, and objects on the island have been dated to 500 to 4,000 years ago.
Santa Barbara Island seemed undesirable, thought only to have had a few reliable seeps of fresh water in the past. (Now there's nothing.) This year, however, a team–including Perry and folks from the University of California–Santa Barbara; the Channel Islands National Park; and Beyond Maps, a cartography company–undertook a re-survey of the island. The do-over brought the number of known archaeological sites on the island from 19 to 63, and they've convinced Perry that whole families sometimes lived on Santa Barbara. "They are setting up shop," she says. "They're bringing everything, including the metaphorical kitchen sink."
One important question is how these Gabrieleños gathered enough water to use. Perry has an interesting hypothesis. Her team has found concave stones on high points on the windward side of the island. People must have hauled the rocks up from the beach. "They're not just naturally sitting on the plateau," Perry says. She thinks these stones may have acted as fog-catchers. People could tuck them under low, scrubby plants, whose branches would collect and condense thick mist rolling off the ocean, and drip onto the stones. One or two stones might be enough to harvest enough water to support a person for a day.
There's no direct evidence of ancient Californians using fog-catchers, but archaeologists have found other structures that they used to control water, including a canal on Catalina Island and water caches on the mainland. "There's this constant manipulating of things to enhance where water is and to store water," Perry says. "That's constantly on people's minds." Living off fog would also help explain why Santa Barbara Island's largest and densest concentration of archaeological sites are on the windward side, whereas, typically, people try to build out of the way of the wind. "It's total conjecture," Perry says. "But there's so many indirect lines of evidence" suggesting Santa Barbara Islanders once lived off the moisture in the air.
"People are much more fluid, innovative, and flexible than we give them credit for," Perry says. "People understand their environment very well and can choose novel strategies to deal with that. They're not stuck on one trajectory. I think that's important today, especially when we think about climate change. I think that's part of the importance of the past, to think: 'There are different choices we could be making.'"
The ingenuity people needed to muster to get a good drink of water also means that someone must have really cherished that soapstone cup. "I just love artifacts that connect you to an individual. This was somebody's cup," Perry says, making an excited "wahhh" sound as she does. Maybe the cup's owner once squatted on the same plateau as Perry did, to grab a drink and get a different perspective on things.