Reaching the Twin Tanks area in Joshua Tree National Park from the Twin Tanks backcountry board requires a little bit of a hike, either cross country proper or up a wide wash.
The tanks referred to are dams built by cattle ranchers to enhance natural tanks that were used for years prior by the Native Americans who lived in the area.
The tanks are interesting enough by themselves, but today’s entry is about the older history of the area.
Directly below the larger of the two tanks is a narrow chasm cleft into the granite by years of flash floods from winter rains. Along the eastern side of this chasm, directly below the stone and mortar of the tank, are numerous cupules, carefully ground into the surface.
One of the Twin Tanks, with the cupules below it.
For all their apparent simplicity cupules are a very exciting find. Besides being one of the oldest forms of rock art in Northern America ( indicating likely great age to any sites they appear at ) they have some very interesting theories surrounding them.
The cupules are concentrated all along the scalloped side of the monolith.
In certain parts of California the ethnographic record directly supports their role in fertility rites. Women ground them into “baby rocks” in the hopes of transferring some of the rock’s strength to themselves so they could be assured healthy offspring.
In other parts of the state they are also present but no ethnographic record directly supports this interpretation. This doesn’t mean that their function wasn’t the same – it only means that we don’t have direct evidence.
The placement of these cupules are evocative. The seasonal rains provide water, associated with growth, and these cupules are ground into the surface right at a tank that would have held water.
A closer look. The cupules are fairly shallow and of uniform size.
The surrounding area doesn’t hold much evidence of habitation. There are no readily inviting rock shelters nearby. These cupules were likely ceremonial. Maybe they were a way of giving thanks for the water found below them, maybe they were associated with fertility rituals or other rituals. We don’t know.
Today they endure in solitude occasionally broken by visitors. The activity in the area at the time they were created is long gone and the cattlemen have also left: their enterprise, built on the hope that a brief unusually wet period was normal, fizzled out quickly.
If you visit, respect both the cupules and the tank above it. They are part of the area’s history, preserved by visitors like you who did not damage them. Pass that along to those that will visit after you.