early 4,000 metres (xiii,000 feet) underwater in the Pescadero basin in the Gulf of California lie some of the Pacific’due south deepest hydrothermal vents – and they’re covered in small iridescent worms. “You’ll run into trivial pinkish sparkly worms, blue ones, red ones, black ones and white ones,” says Avery Hiley, a graduate researcher at the Scripps Institution of Oceanography in San Diego.
These are hungry calibration-worms, or
meaning “hungry” or “famished” in Greek – named every bit such considering they were first establish clustered effectually a pile of food that scientists had left experimentally on the deep-sea floor. For years they accept been nicknamed “Elvis worms” for their sparkling scales, reminiscent of the sequined jumpsuits worn by Elvis Presley.
In that location are six known species of hungry scale-worms, all roughly thumb-sized and living in the deep body of water, including four named in 2020. One of these, which boasts a coat of shimmering pink scales, is specifically named after the king of stone’n’scroll – Hiley and her colleagues named information technology
Hungry calibration-worms have been found on the carcasses of dead whales, and on volcanic seamounts, hydrothermal vents, and cold seeps, where marsh gas trickles up through the seabed like champagne bubbles.
It is likely the worms are feeding on chemical-harnessing leaner that abound on all these habitats. “They have jaws which we suspect they employ to graze bacteria,” says Hiley. “Then, we do think they’re bacteriovores.”
When Hiley and colleagues carried out genetic tests of the hungry scale-worms from the Pescadero basin, what they causeless were multiple species, each with its own color, turned out to be a single species. “Nosotros realised that with age information technology seems that [the] species changes in color, as it develops from a juvenile to an developed class.”
The worms’ colours are created non by pigments but past light reflecting and refracting within the internal construction of the scales, in the same way as with shining blue butterfly wings. The merely light bachelor in the deep ocean to brand them sparkle is the bioluminescence of other animals, merely they gleam brilliantly in the headlights of deep-diving robots and submersibles.
It’s possible that as worms become older their color changes because their scales grow thicker, altering how low-cal passes through them. The thickest scales are bluish. Slightly thinner are pink. “The littlest worms tend to always exist white and the scales are very flimsy,” says Hiley.
Previously, when scientists collected specimens of hungry scale-worms, many had fries in their thick scales; they assumed their scales were damaged while being picked up by a deep-diving robot and transferred to the surface. So, in 2017 at the Pescadero basin, a rare scene was caught on camera. “It turns out, actually, this species does this fighting ritual,” says Hiley.
Hungry scale-worms bounce on the spot and throw punches at each other, inverting their snout and biting chunks out of each other with their powerful jaws. “It was a slice of the puzzle that we didn’t know for a long fourth dimension,” says Hiley.
It is still non clear why the worms fight each other. “We have more observation to practise, definitely,” she says.
1 more puzzle that Hiley wants to solve is how hungry scale-worms evolved from ancestors living in shallow seas to be able to survive in the low-oxygen, hyper-pressurised environment of the deep sea. She is looking for clues in their genes.
“We are starting to see some weird things on a genetic level with these abyssal worms,” says Hiley. The 29 species of deep-sea scale-worms, including the hungry species, have a huge variation in their factor order compared with species of worms that live in shallow seas. Hiley is investigating whether this may somehow help explain how the worms take adapted to the rigours of the deep sea.