The beautiful bioluminescence of the Bermuda fireworm (Odontosyllis enopla), which lives throughout the Caribbean, was first documented in 1492 by Christopher Columbus and his crew just before landing in the Americas. The observations described the lights as “looking like the flame of a small candle alternately raised and lowered.”

The phenomenon went unexplained until the 1930s, when scientists matched the historic description with the unusual and precisely timed mating behavior of fireworms. During summer and autumn, beginning at 22 minutes after sunset on the third night after the full Moon, spawning female fireworms secrete a bright bluish-green luminescence that attracts males. “It’s like they have pocket watches,” said lead author Mercer R. Brugler, a Museum research associate and assistant professor at New York City College of Technology (City Tech).

“The female worms come up from the bottom and swim quickly in tight little circles as they glow, which looks like a field of little cerulean stars across the surface of jet black water,” said Mark Siddall, a curator in the American Museum of Natural History’s Division of Invertebrate Zoology and corresponding author of the study. “Then the males, homing in on the light of the females, come streaking up from the bottom like comets — they luminesce, too. There’s a little explosion of light as both dump their gametes in the water. It is by far the most beautiful biological display I have ever witnessed.”

To further investigate this phenomenon, Siddall, together with Brugler; Michael Tessler, a postdoctoral fellow in the Museum’s Sackler Institute for Comparative Genomics, and M. Teresa Aguado, former postdoctoral fellow in the Museum’s Sackler Institute for Comparative Genomics who is now at the Autonomous University of Madrid, analyzed the transcriptome — the full set of RNA molecules — of a dozen female fireworms from Ferry Reach in Bermuda.

Their findings support previous work showing that fireworms “glow” because of a special luciferase enzyme they produce. These enzymes are the principal drivers of bioluminescence across the tree of life, in organisms as diverse as copepods, fungi, and jellyfish. However, the luciferases found in Bermuda fireworms and their relatives are distinct from those found in any other organism to date.

“It’s particularly exciting to find a new luciferase because if you can get things to light up under particular circumstances, that can be really useful for tagging molecules for biomedical research,” said Tessler.

The work also took a close look at genes related to the precise reproductive timing of the fireworms, as well as the changes that take place in the animals’ bodies just prior to swarming events. These changes include the enlargement and pigmentation of the worms’ four eyes and the modification of the nephridia — an organ similar to the kidney in vertebrates — to store and release gametes.

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Materials provided by American Museum of Natural History. Note: Content may be edited for style and length.

Researchers at MIT have now embedded high speed optoelectronic semiconductor devices, including light-emitting diodes (LEDs) and diode photodetectors, within fibers that were then woven at Inman Mills, in South Carolina, into soft, washable fabrics and made into communication systems. This marks the achievement of a long-sought goal of creating “smart” fabrics by incorporating semiconductor devices — the key ingredient of modern electronics — which until now was the missing piece for making fabrics with sophisticated functionality.

This discovery, the researchers say, could unleash a new “Moore’s Law” for fibers — in other words, a rapid progression in which the capabilities of fibers would grow rapidly and exponentially over time, just as the capabilities of microchips have grown over decades.

The findings are described this week in the journal Nature in a paper by former MIT graduate student Michael Rein; his research advisor Yoel Fink, MIT professor of materials science and electrical engineering and CEO of AFFOA (Advanced Functional Fabrics of America); along with a team from MIT, AFFOA, Inman Mills, EPFL in Lausanne, Switzerland, and Lincoln Laboratory.

Optical fibers have been traditionally produced by making a cylindrical object called a “preform,” which is essentially a scaled-up model of the fiber, then heating it. Softened material is then drawn or pulled downward under tension and the resulting fiber is collected on a spool.

The key breakthrough for producing these new fibers was to add to the preform light-emitting semiconductor diodes the size of a grain of sand, and a pair of copper wires a fraction of a hair’s width. When heated in a furnace during the fiber-drawing process, the polymer preform partially liquified, forming a long fiber with the diodes lined up along its center and connected by the copper wires.

In this case, the solid components were two types of electrical diodes made using standard microchip technology: light-emitting diodes (LEDs) and photosensing diodes. “Both the devices and the wires maintain their dimensions while everything shrinks around them” in the drawing process, Rein says. The resulting fibers were then woven into fabrics, which were laundered 10 times to demonstrate their practicality as possible material for clothing.

“This approach adds a new insight into the process of making fibers,” says Rein, who was the paper’s lead author and developed the concept that led to the new process. “Instead of drawing the material all together in a liquid state, we mixed in devices in particulate form, together with thin metal wires.”

One of the advantages of incorporating function into the fiber material itself is that the resulting fiber is inherently waterproof. To demonstrate this, the team placed some of the photodetecting fibers inside a fish tank. A lamp outside the aquarium transmitted music (appropriately, Handel’s “Water Music”) through the water to the fibers in the form of rapid optical signals. The fibers in the tank converted the light pulses — so rapid that the light appears steady to the naked eye — to electrical signals, which were then converted into music. The fibers survived in the water for weeks.

Though the principle sounds simple, making it work consistently, and making sure that the fibers could be manufactured reliably and in quantity, has been a long and difficult process. Staff at the Advanced Functional Fabric of America Institute, led by Jason Cox and Chia-Chun Chung, developed the pathways to increasing yield, throughput, and overall reliability, making these fibers ready for transitioning to industry. At the same time, Marty Ellis from Inman Mills developed techniques for weaving these fibers into fabrics using a conventional industrial manufacturing-scale loom.

“This paper describes a scalable path for incorporating semiconductor devices into fibers. We are anticipating the emergence of a ‘Moore’s law’ analog in fibers in the years ahead,” Fink says. “It is already allowing us to expand the fundamental capabilities of fabrics to encompass communications, lighting, physiological monitoring, and more. In the years ahead fabrics will deliver value-added services and will no longer just be selected for aesthetics and comfort.”

He says that the first commercial products incorporating this technology will be reaching the marketplace as early as next year — an extraordinarily short progression from laboratory research to commercialization. Such rapid lab-to-market development was a key part of the reason for creating an academic-industry-government collaborative such as AFFOA in the first place, he says. These initial applications will be specialized products involving communications and safety. “It’s going to be the first fabric communication system. We are right now in the process of transitioning the technology to domestic manufacturers and industry at an unprecedented speed and scale,” he says.

In addition to commercial applications, Fink says the U.S. Department of Defense — one of AFFOA’s major supporters — “is exploring applications of these ideas to our women and men in uniform.”

Beyond communications, the fibers could potentially have significant applications in the biomedical field, the researchers say. For example, devices using such fibers might be used to make a wristband that could measure pulse or blood oxygen levels, or be woven into a bandage to continuously monitor the healing process.

This transport could not have begun much before 2.5 billion years ago, according to new research by Washington University in St. Louis, published in the August 9 issue of the journal Nature.

“Life on Earth cares about changes in the volatile budget of the surface,” said Rita Parai, assistant professor of geochemistry in Earth and Planetary Sciences in Arts & Sciences and first author of the study. “And there’s an interplay between what the deep Earth was doing and how the surface environment changed over billion-year timescales.”

Volatiles — such as water, carbon dioxide and the noble gases — come out of the mantle through volcanism and may be injected into the Earth’s interior from the atmosphere, a pair of processes called mantle degassing and regassing. The exchange controls the habitability of the planet, as it determines the surface availability of compounds that are critical to life — such as carbon, nitrogen and water.

The new model presented by Parai and collaborator Sujoy Mukhopadhyay, of the University of California, Davis, also establishes a range of dates during which the Earth shifted from a net degassing regime — again, think about those oozy volcanoes — to one that tilted the balance to net regassing potentially enabled by subduction, the conveyor-belt action of tectonic plates.

Mechanical properties change as water is added or removed from the mantle, so the onset of regassing had an important effect on the internal churning of the mantle, known as convection, which controls plate motions at the surface, Parai said.

Parai uses noble gases to address questions about how planetary bodies form and evolve over time. In this new research, she modeled the fate and transport of volatile compounds into the Earth’s mantle using xenon isotopes as tracers.

“Xenon is an excellent volatile tracer, because all minerals that carry water also carry xenon,” Parai said. “So if xenon regassing was negligible, water regassing must also have been negligible during the Archean (4 billion-2.5 billion years ago).”

Substantial regassing began sometime between a few hundred million to 2.5 billion years ago, the researchers found.

If plate tectonics and subduction began earlier than 2.5 billion years ago, then perhaps by then the Earth’s interior had cooled sufficiently for volatiles to remain in subducting plates, rather than getting released and percolating back to the surface through magmatism, Parai suggests.

“Most people rarely have an occasion to think about volatiles trapped in the Earth’s interior,” Parai said. “They’re present at low concentrations, but the mantle is huge in terms of mass. So for the Earth’s total volatile budget, the mantle is an important reservoir.”

She plans to focus her future research on pushing the limits of precision in xenon isotopic measurements in a variety of geological samples.

“The more observational constraints we have, the better,” she said.

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Materials provided by Washington University in St. Louis. Original written by Talia Ogliore. Note: Content may be edited for style and length.