My blog this week is about creatures of the deep. Obviously, I love marine science, so I thought it would be really interesting to take a look at the scary looking creatures that live 1000's of meters below the surface. Who lives there? How do they survive? What are some common characteristics? What fish was found the deepest?
- Epipelagic: Top layer of ocean near the surface where the water is warmed by the sun and photosynthesis is most effective.
- Mesopelagic: Mid-ocean layer between 200m and 800m where sunlight can still penetrate.
- Bathypelagic: Deep-water between 800m and 4,000m where sunlight penetration is extremely low.
- Benthopelagic: The layer of water just above the seafloor.
- Abyssal: The sea floor.
- Hadopelagic: The really really deep ocean water that is found within trenches.
Now that we know all that, lets take a look at who lives there:
Viper Fish
Rat Tail
Okay, you get the point... these guys are UGLY!!!
How do they survive all the way down there?:
Many species of deep ocean fish have special adaptations to living in extremely high pressure, low light conditions. Viper fish (Mesopelagic - found at 80-1600 meters - about a mile down) are some of the most wicked looking fish dredged up from the depths. Some of them are black as night all over with light organs (called photophores) in strategic places on their bodies, including one on a long dorsal fin that serves as a lure for the fish it preys upon. Some viperfish (and many other deep ocean fish species) don't have any pigment (color) at all - they're "see through". They also have enlarged eyes, presumably for gathering as much light as possible where there is little or no light at all. The light organs create lights by using a chemical process called bioluminescence. Other deep ocean fish, such as the the gulper eel have a hinged skull, which can rotate upward to swallow large prey. They also have large stomachs which can stretch to accommodate a fish much larger than itself. The gulper eel is particularly well-known for its impossibly large mouth - big enough to get its mouth around (and swallow!) creatures much bigger than itself. Fish that live down here must adapt to a very low food supply, eating only "scraps" that sink down from above, or sometimes eating each other.
So who wins the prize for being the deepest fish in the ocean???:
The world's record holder for deepest fish goes to the brotulid family, about which scientists know almost nothing. These fish are benthopelagic, living at depths of 7000 meters or more. The world's deepest fish (Abyssobrotula galatheae) was found in the Puerto Rican Trench at a depth of 8,372 meters (that's over five miles down!).Their eyes appear to be virtually nonexistent. Maybe it's because there is never enough light for the fish to see, so why bother with the eyes? After all, eyes in most organisms are designed for gathering light in the creature's visual field and transmitting it to the brain - giving it useful information about its environment. In a world where no sunlight ever penetrates there's probably little use for eyes. The brotulids probably have other, highly developed senses to compensate for their lack of vision, which help them to find their way around in the dark depths.
All of this info and more can be found at Creatures of the Deep.
