slideshow

A Look at Life in the Deep Sea

These are just some of the animals that live in the deep ocean or in the midwater, the slice of ocean above the seafloor where light is scarce. This vast habitat is filled with billions of animals, many unlike anything you’ve ever seen before. Animals found in the midwater have evolved interesting features and adaptations that are key to their survival in the deep, dark habitat.

Explore these photos taken of organisms found off the coast of California by Dr. Karen Osborn, a curator and zoologist at the Smithsonian National Museum of Natural History. The team used remotely operated vehicles (ROVs) or underwater robots to explore this part of the ocean.

Click through the gallery below to see 15 of Karen’s favorite images!

Aegina, a type of jellyfish, swims through the water.
Corolla moves through the water by flapping a wing plate nearly twice the size of its gelatinous shell, giving it the nickname “sea butterfly”.
Known as “viperfish”, these cryptic fish use their giant teeth to prey on other fish and can grow to be 2 feet long (24 inches).
Bathochordaeus stygius are filter feeders closely related to sea squirts in the phylum Chordata, the same phylum to which humans belong.
Aegina citrea are stealth predators that push their tentacles ahead of their body or bell as they swim through the water.
Chuniphyes are siphonophores—colonial organisms in the same phylum as jellyfish, working together to survive.
Cystisoma (a type of hyperiid crustacean) has one huge pair of eyes.
This female hyperiid (Phronima sedentaria), a type of marine crustacean, is surrounded by her young inside the hollowed out barrel-shaped body cavity of a salp.
These shrimp-like crustaceans called Gnathophausia are incredibly hardy and only need to eat every few months.
This young Gonatus squid is still translucent, making it tricky for predators to spot it.
Like a typical jelly, the tentacles of Haliscera biglowi trail behind it as it moves, causing water flow to push small organisms into the path of the jelly’s deadly stinging grip.
Hastigerinella digitata's many spines support sticky, hair-like “fishing lines” made from cytoplasm (the living part of a cell – mostly fluid, salts and proteins) that entangle prey.
In this photo, the jellyfish Pandea rubra may have been surprised by a camera light or in a defensive state, causing it to contract its red mantle and reveal its complex muscle anatomy.
Rhabdosoma’s uncommon eye arrangement allows the animal to see 360 degrees.
Tomopteris's bristles produce yellow bioluminescence, a unusual color among midwater animals, nearly all of which make some sort of light.
Aegina, a type of jellyfish, swims through the water.

Deep Sea Jellyfish

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Aegina
Amazing adaptation: This jellyfish uses its bell-shaped body and long tentacles to propel itself through the open midwater ecosystem. 
 

Corolla moves through the water by flapping a wing plate nearly twice the size of its gelatinous shell, giving it the nickname “sea butterfly”.

Sea Butterfly

Credit: @ 2012 KJ Osborn, Smithsonian

Scientific name: Corolla sp. 
Amazing adaptation: Corolla are sea snails that catch their prey by producing a mucus net many times the size of its body, and waiting while plankton and other organic material become entangled.

Known as “viperfish”, these cryptic fish use their giant teeth to prey on other fish and can grow to be 2 feet long (24 inches).

Viperfish

Credit: @2012 KJ Osborn, Smithsonian

Scientific name: Chauliodus sp. 
Amazing adaptation: Scientists believe that the photophores (light-emitting organs) seen here underneath the eye are used to signal other viperfish.

Bathochordaeus stygius are filter feeders closely related to sea squirts in the phylum Chordata, the same phylum to which humans belong.

Larvacean

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Bathochordaeus stygius
Amazing adaptation: Larvaceans are filter feeders that build a three-foot-long mucus net to trap savory small particles and keep bigger unwanted particles out. 

Aegina citrea are stealth predators that push their tentacles ahead of their body or bell as they swim through the water.

Lemon Jellyfish

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Aegina citrea
Amazing adaptation: These jellies push their stinging tentacles ahead of their body or bell as they swim through the water to catch prey before their prey even know they are near. 

Chuniphyes are siphonophores—colonial organisms in the same phylum as jellyfish, working together to survive.

Siphonophore

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Chuniphyes sp. 
Amazing adaptation: Siphonophores are colonial organisms in the same phylum as jellyfish and possess a chain of alternating feeding stomachs that can grow indefinitely.

Cystisoma (a type of hyperiid crustacean) has one huge pair of eyes.

Cystisoma Amphipod

Credit: © 2012 KJ Osborn, Smithsonian

Scientific name: Cystisoma sp. 
Amazing adaptation: This crustacean has one huge pair of eyes (the entire surface of its head, including the orange sheet of retinal cells!) that look almost exclusively upwards, possibly to watch out for animals overhead.

This female hyperiid (Phronima sedentaria), a type of marine crustacean, is surrounded by her young inside the hollowed out barrel-shaped body cavity of a salp.

Phronima Amphipod

Credit: © 2012 KJ Osborn, Smithsonian

Scientific name: Phronima sedentaria
Amazing adaptation: Phronima eyes see blue light best and are well-suited to look for other animals horizontally out the front of their barrel. 

These shrimp-like crustaceans called Gnathophausia are incredibly hardy and only need to eat every few months.

Lophogastrid

Credit: © 2012 KJ Osborn, Smithsonian

Scientific name: Gnathophausia sp.
Amazing adaptation: The body of this tiny crustacean is red, a common adaptation among deep-water animals. Red is invisible when you shine blue or green light on it, the color of most animals’ bioluminescent searchlights.

This young Gonatus squid is still translucent, making it tricky for predators to spot it.

Deep Sea Squid

Credit: © 2012 KJ Osborn, Smithsonian

Scientific name: Gonatus sp. 
Amazing adaptation: This young squid is translucent, making it tricky for predators to spot it. As it grows, it becomes increasingly costly to keep its muscles transparent, so the squid’s body color changes from white to red.

Like a typical jelly, the tentacles of Haliscera biglowi trail behind it as it moves, causing water flow to push small organisms into the path of the jelly’s deadly stinging grip.

Haliscera Jellyfish

Credit: © 2015 KJ Osborn, Smithsonian

Scientific name: Haliscera biglowi
Amazing adaptation: This jelly’s stomach is red to prevent it from glowing when it eats bioluminescent prey.

Hastigerinella digitata's many spines support sticky, hair-like “fishing lines” made from cytoplasm (the living part of a cell – mostly fluid, salts and proteins) that entangle prey.

Foraminifera

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Hastigerinella digitata
Amazing adaptation: This single-celled organism is a small but ambitious predator, using its many spines to support sticky, hair-like “fishing lines” that entangle prey.

In this photo, the jellyfish Pandea rubra may have been surprised by a camera light or in a defensive state, causing it to contract its red mantle and reveal its complex muscle anatomy.

Red Paper Lantern Jellyfish

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Pandea rubra
Amazing adaptation: When startled, this jelly retracts and coils its long tentacles, which can be up to 6 times its body length.

Rhabdosoma’s uncommon eye arrangement allows the animal to see 360 degrees.

Rhabdosoma Amphipod

Credit: © 2014 KJ Osborn, Smithsonian

Scientific name: Rhabdosoma sp. 
Amazing adaptation: The sphere in the middle of this crustacean’s head is actually a pair of compound eyes containing multiple lenses and retina, allowing the animal to see 360 degrees.

Tomopteris's bristles produce yellow bioluminescence, a unusual color among midwater animals, nearly all of which make some sort of light.

Gossamer Worm

Credit: @ 2012 KJ Osborn, Smithsonian

Scientific name: Tomopteris sp. 
Amazing adaptation: These worms are usually transparent, making it easy to camouflage in the open midwater, except when they take on the color of the prey they’ve just eaten. 

Tags: National Museum of Natural History