Most scorpions glow under an ultraviolet light, but now a discovery on Alcatraz Island reveals that a certain species of millipedes will, too.

Forensic entomologist Robert Kimsey of the UC Davis Department of Entomology, who does fly research on Alcatraz, said that bait laced with a non-toxic fluorescent dye to estimate the rat population in February yielded the expected result: the glow of rat urine and feces.

But something else was glowing nearby: millipedes.

Had they consumed some of the rat bait?

No. An experiment at the Bohart Museum of Entomology on the UC Davis campus showed that these millipedes (Xystocheir dissecta (Wood) glow under black lights, just like scorpions.

Lynn Kimsey, director of the Bohart Museum and a professor of entomology at UC Davis, said the species is a relatively abundant species in the Bay Area. “This particular species of millipedes glowed all along, but nobody was paying any attention to it,” she said.

She suspects that the millipedes on Alcatraz Island originated from soil transported over from the nearby Angel Island when “The Rock” was just that—rock with little or no soil.

Meanwhile, if you attend the Bohart Museum's open house from 1 to 4 p.m. on Sunday, June 3 at 1124 Academic Surge, California Drive, you'll see scorpions and millipedes glowing.

And there's something else to draw you in: a special live display of the California dogface butterfly by naturalist/photographer Greg Kareofelas of Davis. If all goes as planned, an adult will emerge from its chrysalis. If this doesn't happen (well, you can't tell a buttterfly when to emerge!) you can watch the life cycle on his PowerPoint presentation, to run continuously throughout the open house.

And, you can ask Kareofelas all about the California dogface butterfly (Zerene eurydice), which, by the way, is close to royalty--it's California's designated state insect.