In a discovery that blurs the road between biology and know-how, scientists have discovered that heart-shaped clams use fiber optic–like constructions to channel daylight via their shells in a lot the identical means that telecommunications firm use fiber optics to ship high-speed web connectivity into houses.
This innovation, a primary recognized instance of bundled fiber optics in a residing creature, helps to elucidate how coronary heart cockles (Corculum cardissa) — a marine bivalve present in shallow waters throughout the Indian and Pacific Oceans — harness daylight to nourish symbiotic algae residing inside, whereas defending them from dangerous ultraviolet rays. In return, the algae present the clams with sugars and different important vitamins.
The discovering highlights an evolutionary adaptation that parallels human technological ingenuity, and presents potential insights for the event of bioinspired optical methods sooner or later, researchers report November 19 in Nature Communications.
Coronary heart cockles are small, walnut-sized bivalves finest recognized for his or her distinctive shell form. However a detailed look reveals the shells are pockmarked with “home windows” — minute, clear constructions that allow mild to go via.
This distinctive structure is rooted within the particular properties of aragonite, a crystalline type of calcium carbonate (SN:1/21/03). These aragonite crystals are organized in micron-sized tubes that perform like fiber-optic cables, guiding mild with distinctive precision, whereas filtering out dangerous ultraviolet radiation that would injury the clams’ symbiotic algae or their very own delicate tissues.
Evolutionary biophysicist Dakota McCoy, of the College of Chicago, and her colleagues carried out microscope experiments demonstrating that the sun-facing facet of the shell permits greater than twice as a lot photosynthetically helpful mild to penetrate inside because it does dangerous, DNA-damaging ultraviolet mild.
In response to McCoy, this light-filtering capability probably helps cut back the chance of bleaching, a lethal phenomenon affecting each corals and clams alike that’s at present being exacerbated by local weather change (SN: 8/7/24).
Pc simulations additional demonstrated that the association of the fiber optic–like constructions represents an evolutionary trade-off, finely tuned to steadiness the shell’s mechanical power with its potential to effectively transmit mild.
“Lastly, any person has really labored this out,” says Jingchun Li, an evolutionary biologist on the College of Colorado, Boulder, who research the symbiotic relationship between coronary heart cockles and their algae.
The guts cockles aren’t alone in channeling daylight to symbiotic algae. Different marine creatures, reminiscent of large clams, do that too (SN: 6/22/18). However whereas these huge, ridged bivalves depend on specialised cells to attract in helpful daylight, coronary heart cockles, with their shells shut tight, reap the benefits of their distinctive aragonite structure.
“They’re utilizing minerals of their shells to do that and never organic constructions,” says Sarah Lemer, an evolutionary geneticist on the Leibniz Institute for the Evaluation of Biodiversity Change in Hamburg, Germany, who was not concerned within the examine. “It’s actually neat.”
McCoy and others now envision leveraging the properties of aragonite or its intricate lattice constructions to create new supplies with superior optical efficiency — probably revolutionizing wi-fi communication applied sciences and superior measurement instruments.
One high quality they hope to copy is aragonite’s potential to channel mild with out reflective coatings. Such coatings are wanted on telecommunications cables to restrict mild alerts, however aragonite naturally possesses its personal optical containment options.
“By mimicking the bundled fiber constructions present in coronary heart cockles, we might develop methods that supply enhanced mild assortment,” says Boon Ooi, a photonics researcher on the King Abdullah College of Science and Know-how in Saudi Arabia.
“Billions of years of product design have gone into this,” McCoy factors out. Tapping into the center cockles’ shell design, she says, might result in unmatched light-transmission capabilities — leaving the human end-users of those applied sciences as pleased as clams.
