The ocean still holds deep secrets. It was only as recently as 1977 that ‘black smokers’ were discovered by Robert Ballard in a dive near the Galapagos Islands. That’s an apt description of hydrothermal vents; superhot geothermal water comes out of vents and chemical reactions create plumes with metal sulfides and more.
Unique bacteria and animals thrive there. One of them is a worm that clads itself in toxic armor. It is the only multicellular organism (i.e., not a microbe) that can live at the very hottest part of vents in the Okinawa Trench in the Pacific Ocean. This worm, named Paravinella hessleri, combines sulfur and arsenic to make orpiment. Both the sulfide form of sulfur and arsenic are truly toxic to almost every form of life that’s multicellular (some bacteria can deal with them).
Orpiment itself lends itself to beauty. It’s known to painters as a brilliant golden pigment. Titian, Tintoretto, and others used its brilliant yellow color. Some painters learned too well of its toxicity. The worm itself looks resplendent in its golden coat. How does it take two toxins and escape the lethal effects? The microscopic crystals of orpiment are right inside the worm’s cells. That remains to be discovered. It’s tough to study biological processes at extreme temperatures and pressures!
This has been an outreach activity of the Las Cruces Academy, viewable at GreatSchools.org.
Source: Nature, 11 Sept. 2025, 296
Image: From the article
