Totally Tubular

Researchers have finally cracked the case involving a bizarre deep-sea fish that has a transparent head and rotating tubular eyes

By Brooke Borel Posted 02.25.2009 at 1:08 pm 10 Comments

Barreleye The fish's tubular eyes are capped by bright green lenses. The eyes point upward when the fish is looking for food overhead. They point forward when the fish is feeding. The two spots above the fish's mouth are are olfactory organs called nares, which are analogous to human nostrils. MBARI

Ever since the fish's discovery in 1939, scientists have believed that the tube-shaped eyes of Macropinna microstoma, commonly called the "barreleye," were fixed in place, limiting its vision to whatever was directly overhead. Recent research from Monterey Bay Aquarium Research Institute (MBARI) proves this theory wrong: in reality, this crazy fish can rotate its eyes from an overhead view, which helps it locate prey swimming above, to the front of its face. This helps explain how the fish is able to actually capture the prey with its tiny mouth.

The MBARI scientists observed the fish up to half a mile below the ocean surface using remotely operated vehicles -- robot submarines equipped with high-def video cameras -- and they captured their eerie green, moveable eyes on film (see video). They also were able to capture a live barreleye, and observe the eye movement in person in an aquarium aboard their research ship.

The fish likely evolved this way in order to survive in the pitch-blackness of the deep sea. Its super-light-sensitive eyes make out shadows and shapes of prey above. Once it spots a potential meal, the eyes shift forward and the fish swims towards it. If all goes according to plan, it has a tasty treat. The researchers think that the green pigment in the eyes may help the fish locate bioluminescent prey, including jellyfish, by filtering out the rare sunlight that does make it to the sea depths.

The new research also turned up another surprising fact about the fish: its head is enclosed by a see-through, fluid-filled shield. The researchers speculate that the fish not only eats jellyfish, but also steals copepods and other small animals trapped in the jellyfishes' tentacles. The shield likely helps protect the eyes from jellyfish stings during this thievery.

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10 Comments

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Meisem

02/26/09 at 12:09 am

Wow, that truly is incredible. It just goes to show that there are so many strange and weird creatures down in the oceans, including ones we still haven't discovered.

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SpeedyB

02/26/09 at 11:09 am

A fish with a built-in visor thats very cool. Looks like some kind of alien fish.

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dipap

02/26/09 at 1:20 pm

This is really far out! My first reaction, i have to admit was " cryptozoology hoax" but i don't know... it does look very impractical from an evolutionary point of view, even in the depths. Either way, nature never stops to amaze anyway and it doesn't give a damn about what i think is practical.
Love to see some more videos though.

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thunderstorm

02/27/09 at 11:40 pm

This is amazing. Just goes to show how much God still has to show us and science.

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stempo4

03/03/09 at 1:20 am

Wow, that is so wonderful, let's hope we don't destroy this amazing creature, as we tend to destroy everything.

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randallflagg

07/09/10 at 4:56 pm

The scientists observed the fish up to half a mile below the ocean surface using remotely operated vehicles and that is totally cool with me.
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maradonasports

09/15/10 at 4:57 am

Really impressed! Everything is very open and very clear explanation of issues. It contains truly information. Your website is very useful. Thanks for sharing. Looking forward to more!
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HarryKK

10/26/10 at 4:18 am

Well, i agreed on above comments..we should preserve such wonderful creature and we should not destroy them..This fish is beautiful creature..
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soodsoi

11/26/10 at 8:15 am

Wow, that is so wonderful, let's hope we don't destroy this amazing creature, as we tend to destroy everything
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