There are dozens of tiny eyes—up to 200—along the edge of the muscular tissue lining a scallop’s shell. They are different from our eyes, eschewing a conventional lens to favor “living mirrors” made from guanine crystals, a highly reflective material found in the likes of chameleon skin and fish scales.
While guanine crystals often take on a bulky prism-like shape, marine bivalve crystals are submillimeter squares that create smooth surfaces. Museum scientist and mollusk expert Dr. Suzanne Williams explains in this Natural History Museum London video:
“The scallop eye mirrors focus light onto the retina, much as the mirrors in a reflecting telescope. And these result in an inverted but surprisingly clear image. They likely use their vision to detect and escape predators by jetting or swimming away.”
“Recent studies have shown that some species of scallop are drawn to light, and this has resulted in an innovative new method of fishing that is more sustainable: Instead of using a net to drag along the sea floor, fishermen can now use lobster pots equipped with little LED lights, a bit like an underwater disco.”
This Fishtek Marine promo video shares more about how scallop potting with lights avoids the use of harmful dredges that “are widely reported to cause damage to sensitive marine habitats and species.”
Watch this next: Scallops have lots of tiny eyes that act like tiny telescopes.
Plus, more sustainable fishing methods:
• Underwater farms vs. climate change?
• MarinaTex, a bioplastic made from fish waste
• How To Save Our Coastal Seas: Marine reserves and smart fishing
Bonus: How to make a light trap.