An international collaboration of scientists recently led a monthlong expedition to study the deepest point on earth in the Marianas Trench, the Challenger Deep. Researchers found evidence suggesting a trench teeming with life, footage of a new fish species, as well as various samples that may answer questions about deep-sea life in the future, according to the expedition\u2019s co-chief scientist, Dr. Jeff Drazen, in an exclusive interview yesterday.<\/p>\n
Researchers aboard the R\/V Falkor explored life in what is called the \u201chadal zone,\u201d which comprises some of the least explored and greatest depths in the ocean. The zone begins at about 6,000 meters and drops down the Challenger Deep, nearly 11,000 meters under the sea.<\/p>\n
\u201cThe deep sea is generally unexplored,\u201d Drazen said. \u201cWe have better maps of the surface of the moon than we do of the bottom of the ocean.\u201d<\/p>\n
Trench research can be \u201cvery, very challenging,\u201d because of pressure from the distance to the surface of the sea, according to Drazen. For this research, they used landers\u2014platforms that hold sampling equipment like cameras, baited trap, metal grabs, or cores.<\/p>\n
Drazen said there were a lot of custom-made titanium housing and customized cameras and sensors, as well as \u201cthe first very deep oxygen sensors in the world\u201d on some of their gear.<\/p>\n
The engineering, according to Drazen, helped researchers sample the hadal life that they discovered was \u201cfascinating and rich.\u201d<\/p>\n
\u201cI think some of the mistakes some scientists have made in the past is they have charged to the deepest part of the trenches. There\u2019s actually not as much there as in many other places,\u201d he said, recalling director James Cameron\u2019s 2012 expedition in the trench where Cameron drove straight down the Challenger Deep for 20 or 30 minutes, and eventually described it as a \u201cmonotonous plain of mud,\u201d according to Drazen.<\/p>\n
\u201cWe took a very different approach. We sampled the sides of the trenches. That\u2019s where all the action is. \u2026The camera systems saw boulder fields, and some crazy Dr. Seuss-like sponges, and a really diverse array and abundant groups of fishes.\u201d<\/p>\n
Ethereal fish<\/strong><\/p>\n The researchers also discovered a new species of snailfish.<\/p>\n \u201cYou can see right through the body,\u201d Drazen said of the snailfish. \u201cYou can see their liver, their bones.\u201d<\/p>\n In their discovery, researchers broke the deepest record of fish several times; the first time at 7,900 meters, the last at 8,143 meters. <\/p>\n They recorded the fish accidentally, according to Drazen, through a task camera intended to check on the functionality of equipment.<\/p>\n Technicians first saw the fish, he said, and called the fish biologists over.<\/p>\n \u201cWe sat down and they played it for us. And as it swam into the field of view, we just were totally surprised. Not that there was fish, but just at what it was. It looked so different than any other fish that we knew of in the hadal zone, or anywhere else in the deep sea.\u201d<\/p>\n \u201cWe knew it was a new species immediately,\u201d he added. Footage of the \u201cethereal\u201d and ghost-like snailfish can be viewed online.<\/p>\n Scientists looked for the fish as far as 8,300 meters but did not observe them there, according to Drazen. The furthest they saw the fish was at 8,143 meters, he said, and none were found at 8,200 m.<\/p>\n This, according to Drazen, lined up with the hypothesis of another scientist on board which basically said that no fish live beyond 8,400 meters deep as they are not molecularly suited to survive those deep pressures.<\/p>\n Researchers were able to catch several dozens of the shallower snailfish species but not of the deeper, newly discovered one. From what they have, scientists will study the fish to see what they eat, and how old they are. <\/p>\n Drazen said they would know more in the coming months.<\/p>\n \u2018Giant beach fleas\u2019<\/strong><\/p>\n Scientists also caught giant amphipods\u2014as large as 30 cm\u2014that to average beachgoers may look like beach flies, according to Drazen.<\/p>\n They deployed 30 baited traps that also caught fish and shrimp, he said.<\/p>\n The samples revealed a surprising discovery about the physiology of the amphipods, as they were composed mostly of liquid, according to Drazen.<\/p>\n \u201cWe opened them up and it was all liquid inside. It was like they were hollow. We had to scrounge to find little bits of muscle. There is almost nothing in them. We\u2019re still trying to find out why that is. We\u2019re not entirely sure.\u201d<\/p>\n Right now, their leading hypothesis is that these arthropods have evolved to become significantly large so that predators would not eat them, according to Drazen. <\/p>\n \u201cOne adaption to become very successful in this kind of environment, we think, is you become very large so you can\u2019t fit in these predators\u2019 mouths any longer. But you don\u2019t want to just get big and pay all the energetic costs of growing large. So we think they build their skeleton up and they don\u2019t put very much inside of it,\u201d he said.<\/p>\n The secondary advantage of this adaptation is that amphipods can \u201cgorge\u201d themselves if they find dead fish on the seafloor, Drazen said.<\/p>\n \u201cIf we actually caught some of these amphipods that had been feeding on bait for hours and hours on end, my guess is that they would have a gigantic gut just full of bait.\u201d<\/p>\n Muscles were found along their skeleton shell, a digestive tract and stomach near the center, and a nerve network and brain around the head of the animal, according to Drazen.<\/p>\n But he emphasized that more detailed study must be done.<\/p>\n \u201cI don\u2019t know what [the inner fluid] is composed of,\u201d he said.<\/p>\n Teeming with life<\/strong><\/p>\n Scientists also measured the activity of the mud in the deepsea floor. They did this through measuring how fast sediment organisms breathed, or how fast they used oxygen.<\/p>\n Researchers discovered that the rate at which the mud communities were using oxygen was similar to organisms at shallow depths near the surface, according to Drazen.<\/p>\n He said the rates were \u201cway higher than anything measured in other parts of the deep sea,\u201d and more similar \u201cto what you find off the Mississippi River delta.\u201d<\/p>\n Drazen said the trench can acts as a \u201cfunnel\u201d for detritus that comes from the surface, because of how the trench is shaped, and how sediments often slide downs from its sides.<\/p>\n This has led researchers to think that the trench is a \u201cbiological hotspot.\u201d<\/p>\n \u201cThat\u2019s not what you usually you find in the deep sea. The farther you get from the surface of the ocean, the less food there is. We think the [Mariana] Trench is very unique. There actually may be more food the deeper you go in the Trench,\u201d he said.<\/p>\n He added that he could speak more definitely on the matter once more analysis is done. Extensive study would probably begin early next year, he said, with updates possibly available around the middle of the year.<\/p>\n","protected":false},"excerpt":{"rendered":" An international collaboration of scientists recently led a monthlong expedition to study the deepest point…<\/p>\n","protected":false},"author":47,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[900,4],"tags":[42,21,250,44],"class_list":["post-188153","post","type-post","status-publish","format-standard","hentry","category-featured","category-local-news","tag-food","tag-life","tag-network","tag-study"],"_links":{"self":[{"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/posts\/188153","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/users\/47"}],"replies":[{"embeddable":true,"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/comments?post=188153"}],"version-history":[{"count":0,"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/posts\/188153\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/media?parent=188153"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/categories?post=188153"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.saipantribune.com\/index.php\/wp-json\/wp\/v2\/tags?post=188153"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}