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  • You unlock this world with a deep sea submersible.

  • At 1000 meters youre moving into a world of both shadows and wet substance,

  • of things and stranger things, you've just crossed intothe bathypelagic zone.

  • Hello there landlubbers, Julian here for DNews. Until July 10, 2016,

  • the National Oceanic and Atmospheric Administration ship Okeanos

  • will be over the deepest part of the Pacific ocean, the Marianas Trench, working 24 hours a day studying the ocean floor.

  • And luckily for you, you can watch the live stream and have the chance to see creatures no person has ever seen before.

  • Theyll be exploring areas of the ocean past the point where a little light gets through,

  • called the mesopelagic ortwilightzone, into a sea of constant darkness called the bathypelagic ormidnightzone.

  • Most of the volume of the world’s oceans is in the bathypelagic zone.

  • Even deeper than that, from 4 km to 6 km down is the abyssopelagic zone, akaThe Abyss.”

  • The Okeanos diving robots bottom out at 6 km in depth, where most of the seafloor is,

  • but the marianas trench can cut as deep as 11 km. When you look at the life forms at these depths,

  • the bathypelagic and abyssopelagic might as well be another planet.

  • Giant isopods, viperfish, gulper eels, glowing jellyfish, almost everything looks like a nightmare or a fever dream.

  • Even shrimp that cluster around hydrothermal vents are oddly pale and ghostly,

  • why does everything look so weird down here?

  • Well like all animals, their environment plays a huge role in their evolution,

  • and the deep sea is about as extreme an environment you can find. The biggest factor is the pressure.

  • For every kilometer you dive down, pressure becomes a hundred times greater than the air pressure we experience on the surface.

  • That means at the ocean floor a body would have to withstand 600 times the pressure it would up here.

  • To do that it helps to be flexible, with soft bodies or cartilage that bends without breaking.

  • More watery bodies keep them from compressing, and

  • it’s hypothesized that an elongated shape would help organisms cope with pressure too,

  • which would explain the abundance of eel-shaped fish in the depths.

  • Flat rays would really feel the pounds per square inch across their large area bodies.

  • The pressure even affects deep sea life at a cellular level.

  • Their cell membranes need more unsaturated fats to keep them liquid,

  • otherwise their walls would become crushed and frozen solid and they wouldn’t function.

  • Inside they have more organic molecules called piezolytes, which bind to water and keep their proteins from being distorted.

  • Fish also need to find new ways to manage their buoyancy down there.

  • Gas bladders that fish near the surface use would be crushed, so species develop workarounds.

  • The blob fish’s flesh is gooey and low density. At depth the water crushes it into a workable shape, but

  • unfortunately for the blobfish when we catch them and bring them to the surface they puff out and

  • become the poster child for ugly animals. Other fish have fins so long they act as a tripod,

  • allowing them to stand on the ocean floor. The long stilts sense vibrations and help them catch prey.

  • That’s another problem in the deep: food scarcity. Since no light penetrates there is no plant life.

  • Everything either survives off falling dead organic matter, chemicals coming out of occasional plumes,

  • or the rare other living organisms they find. Unique hunting

  • strategies are adopted, like anglerfish that lure in prey with bioluminescent light.

  • They rely on ambush because it takes less energy, and have slow metabolisms to stretch out each meal.

  • Anglers, viperfish and fangtooths have long teeth that trap prey like a cage.

  • Other fish use lights to confuse predators, and some predators use lights to see, like lanternfish.

  • Many animals have given up on sight entirely and may have non-functioning eyes or no eyes at all.

  • While it’s hard to see and find food this deep, it’s even harder to find a mate.

  • To overcome this, some fish are hermaphroditic, so no matter what mate they bump into they can reproduce.

  • Anglerfish females release pheromones to attract tiny males. When a male comes along, it attaches himself to her,

  • eventually fusing to her and providing sperm in exchange for sustenance.

  • It’s not a hospitable environment, but even at these depths there is still life. Aside from the bizarre nightmare fish,

  • there are also, sponges, sea stars, squid, and crabs. No word on pineapple houses though.

  • Even though there are lots of fish in the sea, were still taking a pretty big bite out of them.

  • To learn about one proposed solution to overfishing check out Trace’s video here.

  • At the moment of international community has agreed to fish in seasons, with catch quotas and minimum size limits -

  • with the hope this would allow time for the fish to mature, spawn and build the population back. News flash, it ain't working.

  • More people have been to the moon than the bottom of the Marianas trench.

  • So would you rather travel to the ocean floor or the surface of the moon? Let us know in the comments. Subscribe for more. And I will see you next time on DNews.

You unlock this world with a deep sea submersible.

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Why Does Deep Sea Life Look So Strange?

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    Freyja posted on 2016/07/29
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