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What lives in the Mariana Trench?


Did you know that more than 80 percent of our oceans are unmapped? That's a huge part of the planet that we don't know a lot about. Sure, space is cool and all, but there are still mysterious hidden places right here on Earth, waiting to be explored... maybe by you!

The Mariana (or Marianas) Trench is a deep-sea trench at the bottom of the western Pacific Ocean. It formed when two tectonic plates collided millions of years ago. At the southern end of the trench is the Challenger Deep, the deepest known point on Earth. At more than 35,000 feet, it's deeper than Mount Everest is high!

The ocean can be divided into different zones. At the very bottom is the hadal zone, named for Hades, the Greek god of the underworld. No light from the surface can reach down there, but there is life! Many amazing species evolved to survive in those extreme conditions.

Total darkness, intense cold and crushing pressure? Home sweet home for the Mariana snailfish! According to National Geographic, it can withstand the water pressure of more than 1600 elephants standing on its head. Super tough for an animal that looks like an oversized pink tadpole.

Lots of other weird and wonderful creatures live in the trench. Sea cucumbers, like the one in the picture. Arrowtooth eels. Acorn worms and spoon worms. Brittle stars and basket stars. Scientists continue to discover new species!

Unfortunately, they are also finding garbage like plastic bags and candy wrappers. A team of scientists collected amphipods (tiny shrimp-like creatures without shells) to study. They found microplastics inside every amphipod! Humans need to do a better job of protecting our oceans. We celebrate World Ocean Day on June 8, but we can help fight plastic pollution and raise awareness year-round. What are some things you can do? Jot down some ideas and take action!

Want to explore underwater worlds without going 20,000 Leagues Under the Sea? Check out cool photos or watch a documentary for your next family movie night. (We love the award-winning Blue Planet series! Deep Ocean: Descent into the Mariana Trench is also on YouTube.)


Image source: the NOAA Office of Ocean Exploration and Research, 2016 Deepwater Exploration of the Marianas

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