Mud Daubers in Luckenbach, Texas
Hondo Crouch bought the town of Luckenbach in 1971 (population: three, plus one parking meter). He liked celebrations. Among other festivals, he fêted the ‘Return of the Mud Daubers.’
Mud daubers played a part in my career in ecology at Oak Ridge National Lab. A less festive part.
On the Oak Ridge Reservation, engineers dug some large earthen pits in the ground, for experimental studies of liquid radioactive wastes. Instruments that monitored the levels of radioactivity sat alongside the pits, sheltered in little wooden boxes. Mud daubers discovered them and built their mud nests inside the boxes. Sometimes they used radioactive mud from the waste pits. The instruments soon began to measure the radioactivity of the mud dauber nests; it overpowered the emanations from the waste pits. The nests had to be removed periodically.
Here’s the fun part. One type of wasp, the black-and-yellow dauber, builds a ‘blob’ nest, rather shapeless. The black-and-blue dauber constructs a neat ‘pipe organ’ nest, rows of clay tubes. (You’ve probably seen both of these types in your garage). Both wasps used the instrument shelters. Some of the “blob” nests were radioactive. But the ‘pipe organ’ nests weren’t. None of them were radioactive. Never.
And we wondered – could the black-and-blue dauber detect waves of radiation, and avoid them? Could they sense atomic radiation? Not a silly idea; wasps can see ultraviolet radiation that’s invisible to us. Maybe they could actually 'see' atomic radiation.
My postdoc, Alvin Shinn, put the daubers in cages and offered them mud. The Black-and-yellow wasp snatched up wads of mud and made nests from it. The black-and-blue dauber carefully selected a little here and a little there; it was a fastidious user of mud. It selected only one type of clay, very carefully. It didn’t like the coarse, radioactive mud.
Was that the answer? The pipe organ builder would use only pure clays? The question remains in my mind. Was the wasp using chemical cues to select clays? Or could it, perhaps, detect radioactivity? Wasps can dig, they can build earthen nests. They can use tools. Are they in line to be the next dominant animals on our planet?