Science and the SeaAuthor: The University of Texas Marine Science Institute
22 Feb 2019

Science and the Sea

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The goal of Science and the Sea is to convey an understanding of the sea and its myriad life forms to everyone, so that they, too, can fully appreciate this amazing resource.

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    Purple, Pink and Blue—and They’re All New

    One is purple, one is pink, and one is blue, and it took 40 scientists from 17 countries to find them, more than 4 miles below the ocean’s surface. They are three new species of snailfish discovered in one of the deepest places on earth, the bottom of the Atacama Trench off the coast of Peru and Chile.

    A team led by researchers at Newcastle University in England has been exploring the deepest parts of the ocean with specialized landers fitted with HD cameras and traps. The landers free-fall to the ocean floor, in this case 24,600 feet below the surface, take photographic and video images, and collect samples. The devices collect data for up to 24 hours before the researchers send an acoustic signal that releases weights in the lander, allowing it to float to the surface so the researchers can collect their scientific booty.

    This research group has already deployed such devices more than 250 times and discovered new snailfish species at the bottom of the Mariana Trench. The Atacama snailfish they found are translucent, eellike fish that lack scales and feed on invertebrates in the trench. Their body tissue is almost entirely gelatinous, well adapted for the extreme conditions at such depths.

    But since they depend on the high pressure and low temperature to stay in one piece, it is extremely difficult for scientists to bring these fragile fish to the surface without them nearly melting away. Nevertheless, researchers managed to bring a live purple Atacama snailfish safely aboard, giving scientists the opportunity to observe and learn from this new species.


  • Posted on 01 Feb 2019

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    Christmas Tree Worms Stay Spirited All Year

    Families that celebrate Christmas will likely have a colorful tree lighting up their living room right now. But under the sea, millions of Christmas tree worms remain festive all year. Christmas tree worms, whose scientific name is Spirobranchus giganteus, have two spiraled crowns on their back that each resemble a tiny colorful Christmas tree.

    These “trees” can be a single solid color but are also often multi-toned, with a second color gracing the outer tips of their spirals like garland. And these worms don’t restrict themselves to red and green. Some are a brilliant blue or bright yellow, while others might be white with orange tips, ruby with white tips, gold with maroon and white tips or any number of other combinations.

    These colorful spirals help the worm breathe and catch food. The worms anchor themselves to coral and use the feather-like tentacles protruding from their spirals to catch tiny prey from the surrounding water and move it to the worm’s mouth. If the worm is startled, it retreats into burrows in the coral to hide from possible predators.

    Over time, these burrows in the coral can reach 10 inches in length, providing a roomy hiding place for a critter that lives up to 30 years. These worms also help coral recover more quickly from bleaching events and protect it from predators. In fact, in perhaps a bit of an ironic twist, scientists have seen Christmas tree worms literally push away the feet of predatory crown of thorns starfish.


  • Posted on 21 Dec 2018

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    Kidnapping Pays Off…for the Captor

    When two unrelated species help each other, their relationship is symbiotic, or mutually beneficial. When one species feeds off another, the feeder is a parasite. But some species find a different way to take advantage of another without consent: kidnapping.

    Scientists have recently learned that amphipods, small crustaceans popularly called scuds or sideswimmers, will do whatever it takes to avoid becoming a predator’s meal—even abducting another species for use as their own personal defense weapons. Several amphipods have been found toting around tiny sea snails, called pteropods, like backpacks, apparently because predators don’t find the sea snails very tasty.

    Amphipods range in size from one millimeter to one foot, though most are less than half an inch long. They look a little like a cross between a shrimp and a flea, and most are scavengers that are the prey of birds and fish. Pteropods are less than a quarter inch long and emit unpleasant chemicals to deter predators. Amphipods have no such secret weapon, so they exploit pteropods by carrying them around. As a result, cod icefish pass them by for meals.

    But this isn’t a symbiotic relationship where the pteropod benefits from palling around with an amphipod. In fact, the pteropod likely starves to death while the amphipod holds it hostage, preventing the pteropod from hunting. Scientists have identified two different amphipod– pteropod species pairings, but they don’t yet know if these are typical pairings or how many amphipod or pteropod species end up in these arrangements. They also don’t know if predators other than cod icefish avoid the pteropod-carrying amphipods—or whether an amphipod would accept a ransom to release a pteropod.


  • Posted on 01 Dec 2018

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    Hogfish and their Amazing Technicolor Skin

    Camouflage is one of the best evolutionary strategies there is for evading predators, and hogfish are masters of it. These pointy-nosed reef dwellers change skin color so rapidly to match their surroundings — literally in milliseconds — that it seems impossible for them to rely only on their eyes to perceive those surroundings.

    As it turns out, they don’t only use their eyes. Hogfish skin can “see” too. Scientists recently analyzed hogfish DNA and learned how this skin vision, called dermal photoreception, works. Hogfish skin cells include chromatophores, which contain a pigment that’s sensitive to light. When these cells sense light patterns, they can mimic those patterns by manipulating the distribution of their pigment, spreading it thin or clustering it together.

    But scientists also wanted to understand how hogfish skin detects light in the first place. Octopus and cuttlefish also rapidly change skin color to blend into their environments. Their skin uses the same basic mechanism that their eyes use. But that’s not how hogfish skin works. Duke University biologists compared genetic material in hogfish skin to genetic material in its retina, the sensory membrane at the back of the eye. They found the fish’s skin and eyes use different genes to detect light.

    Researchers are still studying the molecular chain reaction involved in this newly discovered form of dermal photoreception. They also want to learn how the hogfish combines visual information from the skin and eyes to match its coloration to the environment so quickly. As they learn more, they hope to discover whether this skin-sensing superpower helps hogfish in other ways too. Hogfish and their Amazing Technicolor Skin Hogfish


  • Posted on 01 Nov 2018

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    Sea Serpent…or Surreptitious Shark?

    Sailors’ lore about the ocean has captured popular imagination for centuries, from mermaids and sirens to the mythical Kraken. But often these stories are rooted in a case of mistaken identity. Tales of frightening sea serpents, for example, may have arisen in part from rare sightings of the elusive frilled shark, a long, slender fish that usually lives 400 to 4,200 feet below the surface.

    In fact, in the earliest existing written description of this bizarre creature, Pennsylvania zoologist Samuel Garman wrote in 1884, “its appearance in the forward portion of the body, particularly in the head, brings vividly to mind the triangular heads, deep-cleft mouths, and fierce looks of many of our most dreaded snakes.” The shark’s discovery led Garman to suggest that people should not dismiss too easily the possibility that a “serpent-like monster of the oceans” might actually exist.

    What makes these sharks so fierce are the 300 teeth that are arranged in 25 diagonal rows along its gaping mouth. The teeth all face backward, making it impossible for prey to back out of the shark’s jaws once snagged. Examinations of stomach contents suggest that squid and other cephalopods make up more than half the frilled shark diet. But scientists know almost nothing about their hunting habits.

    There is one problem, however, in blaming these serpentine predators for supposed sea serpent sightings. Although frilled sharks can grow as long as 6 feet, they more typically reach only 3 to 5 feet long, hardly the massive monster that superstitious sailors might fear. Are frilled sharks responsible for myths about sea serpents, or is that possibility a myth itself?


  • Posted on 01 Oct 2018

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