April 04, 2021
The Earth is a big place. With five ocean basins (the Pacific, Atlantic, Indian, Southern and Artic) water covers two thirds of the earth’s surface. Think of the ocean as a layer cake, broken into zones based on sunlight, temperature and water pressure, just not as tasty.
It’s time to preheat the oven, and grab that cake knife to cut into that ocean layer Pinterest cake you’ve been craving.
The Sunlight Zone (Epipelagic Zone) is like the top layer of icing sprinkled with many different toppings (or animals) that call it home. It stretches from the surface down to about 600 feet deep. This is the part of the ocean that gets the most sunlight (or the most instagramable pictures for your cake design), and where plants are able to grow. About 90 percent of all marine life lives in this zone so load that cake up with sprinkles, fruit and rose icing designs.
In nature, animals like Anchor, our great hammerhead shark (Sphyrna mokarran), Pacific blacktip reef sharks (Carcharhinus melanopterus), Bob, our loggerhead sea turtle (Caretta caretta), jellyfish (Scyphozoa) and coral (Anthozoa) are found in this zone.
Think of the Twilight Zone (Mesopelagic Zone) as the first layer of dense chocolate cake beneath the icing.
This layer of the cake, we mean ocean, is about 600 to 3,000 feet beneath the surface. There is very little light and the water pressure starts to build up reaching 5,850 lbs per square inch. While there are a good amount of animals that live in this zone, like crabs (Brachyura), krill (Euphausiacea), squid (Teuthida) and chain dogfish (Scyliorhinus retifer), most have adapted to survive on little light, or to produce their own light. The animals that glow with their own light are "bioluminescent," including some species of squid and jellies.
The deepest, darkest and largest zone of the ocean is called the Midnight Zone (Bathypelagic Zone). This is the ooey, gooey, fudge layer of the cake.
This ocean zone makes up about 90 percent of the ocean, but has rarely been explored because of its extreme conditions. With no light, temperatures that hover just above freezing and water pressure that no human (and most submarines) can withstand, humans have actually explored more of the solar system than this part of planet Earth. Some animals that live here are purple sea urchin (Strongylocentrotus purpuratus) and deep-sea angler fish (Ceratioidei). The sperm whale (Physeter macrocephalus) is able to dive deep into the midnight zone to feed.
The word “abyss” comes from the Greek word meaning “no bottom,” and don’t we all wish there was no bottom to some cakes. In this zone (Abyssopelagic Zone), it is pitch black and extends from 13,000 feet to almost 20,000 feet. There are few sea creatures found at this level, but sea spiders (Pantopoda) and basket stars (Euryalina) do call this dark space home.
This layer of the ocean has our mouths watering thinking about that dark chocolate cake layer.
The Trenches (Hadalpelagic Zone) is the deepest part of the ocean. There is little known about this level of the ocean, but we can’t help but imagine it as that scoop of ice cream next to your cake. It melts and seeps under your cake, and occasionally drips from the countertop to parts of your kitchen you didn’t know existed. The Mariana Trench off the coast of Japan is the deepest known part of the ocean measuring at 36,070 feet deep. Organisms that live here like giant tube worms (Riftia pachyptila), cusk-eels (Ophidiidae) and sea cucumbers (Holothuroidea) eat debris that float down from the upper layers.
Hungry for more cake… we mean, science? When you visit the aquarium, try to figure out what level of the ocean our species can be found, and don’t forget to save us a piece of your oceanic cake!