Saturday, October 31, 2009

Freaky fish? That is not a freaky fish, THIS is a freaky fish!

Oceana (a PAC concerned with oceanic affairs) apparently has an annual "freakiest fish" contest on their blog, the Beacon.  I viewed this year's candidates and am by and large unimpressed; the only fish that I think legitimately belong on that list are the wolf-fish, hairy angler, hagfish and maybe the crown-of-thorns starfish.


Why are coelacanths on there?  Yeah, they're not conventionally attractive, but they're hardly freaky; if anything, their behavior is kind of dull.  And leafy seadragons?  All they do is look pretty!


Past winners of the Freaky Fish voting include:


2008 - Fanfin seadevil.  This is not surprising, as anglerfish ALWAYS excel in this kind of contest.  Seriously, look at that thing.



ANGLERFISH PROTIP: As terrifying as they look, they tend to be pretty small, less than a foot (~30 cm) long; and that's the big females, males tend to be very small and essentially are free-swimming gonads before becoming just plain gonads.  I'll elaborate on this later.


2006 - Blobfish, fangtooth, monkfish.  Blobfish are Internet famous due to an e-mail meme claiming that they're an example of deep sea creatures washed up during a tsunami.  Fangtooth?  Well, they can live in the abyssopelagic zone, which pretty much implies that they're going to be freaky looking.

ABYSSOWHAT?

Abyssopelagic!  TIME TO TALK ABOUT LAYERS (or ZONES) OF THE OCEAN 


"Abysso-" - the abyss.  I'm reasonably sure that everyone reading this knows what "abyss" means/implies.  For our purposes, let's say that it means "stupid deep".  The average person will have no interaction with the abyssopelagic zone due to the pressure/temperature/general conditions down there; for a general idea, here's a demonstration of what happens to styrofoam cups.  The current record for human free-diving is around 530 feet (161.5 m); so, as you can see, without a submersible, even the most enthusiastic human diver will never plunge below the euphotic/epipelagic zone. 


"-pelagic" - if a fish is described as "pelagic", it means it lives in open water, not near/on the bottom of a body of water (those organisms are called "demersal") or in reefs.  There are further subdivisions within these categories, but this definition of "pelagic" will suffice for the time being.



 



It kind of reminds me of the internal structure of the earth:

 
Earth's polar diameter is 7,899.80 miles (12,713.5 km); the average thickness of the continental crust is 21-43.5 miles (35-70 km), while oceanic crust is only 3-6 miles (5-10 km) thick; bear in mind that humans have never even dug to the mantle.  We interact with very little of earth's interior, similarly to how little of the ocean most of us personally access.



Brief tangents into geology aside, the ocean is typically divided into about five layers; only the two uppermost layers receive any light from the sun.  Generally speaking, we're most familiar/comfortable with forms of life that ultimately depend on sunlight to survive, either directly or by consuming organisms that directly use sunlight for life (i.e. plants).  Note I certainly do recognize that abyssopelagic scavengers depend on the sun indirectly, by eating things like dead whales that sink to the ocean floor.  Things that live in places with no sunlight (such as the aphotic zone and deep caves) tend to seem a little freaky to us.



Continuing on though, we have monkfish.  I first encountered monkfish in this context, familiar to readers from the Pacific Northwest:




That is at Seattle's famous Pike Place Fish Market, where fish are tossed daily for your pleasure!  Every time I've visited, they've also had at least one monkfish amid the salmon, with his happy monkfish sign.  If you look closely at them, you'll figure out why they're ugly - monkfish are anglerfish!  

Though I've never had them myself, they've been called "the poor man's lobster" and are evidently tasty enough to have led to an overfishing problem.  They're also known as "headfish" or "goosefish"; monkfish liver used in sushi is called "ankimo".  Research also reveals that their flesh is known to be marketed as a substitute for scallop, so if you're trying to make ethical seafood choices, please read your labels carefully to avoid consuming monkfish.


Okay, I'll admit - the illustration of the John Dory doesn't do this fish justice.  In its blurb, they also neglected to mention that it has protusible jaws, which ups the freak factor considerably.  


Additionally, my research on John Dories allows me to provide you a source for frozen John Dory halves and monkfish!, straight from the marine processors of China!  If that's not enough, how about these tasteful John Dory plates, yours for the princely sum of £29.95 (~$49 US)?

OTHER NOMINEES I OBJECT TO:


The upside-down jellyfish.  Jellyfish have a pretty high base level of "weird"; this one is by and large pretty normal looking, aside from the upside down business, but does that actually surprise anyone?  I personally nominate the granrojo jellyfish (Tiburonia granrojo), Nature's very own Metroid:


 

They're about 2-3 feet wide (60-90 cm), have gross fleshy arms and live 650 to 1500 meters (2000 to 4800 feet) down.  They're not much to say about them, because we don't know much about them.  However, one interesting feature is that their number of arms of variable between individuals.  George Matsumoto, an MBARI (Monterey Bay Aquarium Research Institute) biologist who was lead author on the paper in which granrojo was first described, has this to say about it:



The feature that researchers find most intriguing is a collection of short stumps protruding from Big Red's surface—so- called "oral arms" that might be used for feeding. What mystifies Matsumoto is why some of these jellies have four arms, whereas others have six or seven.

"It is like finding one human with four arms, another with three, and another with two," says Matsumoto. 

 (2003, May 5). Mbari news - big red jelly surprises scientists. Retrieved from http://www.mbari.org/news/news_releases/2003/nr03-matsumoto.html


They're huge, freaky and AWESOME.  The MBARI press release also has links to more images of granrojo, which I strongly recommend you look at.

My final objection is the crown-of-thorns starfish.  Yes, I changed my mind from earlier.  While yes, their appearance is can be kind of concerning, starfish (more appropriately called "sea stars" because they are echinoderms, not fish, but I call cuttlefish "cuttlefish" so I clearly don't care all that much) are by and large a pretty freaky group.


Starfish are popular with children because of their familiar shape.  However, their familiar shape is kind of inherently freaky because they exhibit radial symmetry.  Humans and most animals exhibit bilateral symmetry; that is, we have a left and right side that would more or less match up if we were folded in half along a vertical axis.  Organisms with radial symmetry only have a top or bottom, no right or left.  Think about that for a second and recognize how utterly alien that would be to the human experience, to have no right or left.  The evolutionary biology of starfish

Other organisms that exhibit radial symmetry include jellyfish, some types of sea anemones, sea urchins (bearers of custardy gonads, considered a delicacy in many cultures), sea lilies and many plants. 

Then there's the way that starfish eat.  To put it bluntly, they have two stomach, one which they evert (basically, push out of their bodies) to engulf/digest food, one to further digest food.  Some are able to force their everted stomachs inside the protective shells of soft-bodied mollusks (e.g. clams) to devour them within their own homes.


But as far as plain freaky visual appearance goes, the crown-of-thorns starfish is a non-entity compared to say, the basket star:





Tanenbaum, J. (2006, June 15). Jacob tanenbaum: teacher at sea: 06/01/2006-07/01/2006. Retrieved from http://jacobtanenbaum.com/~tasblog/2006_06_01_archive.html 

I know I am not the only one getting a Lovecraftian vibe from this thing.  Look at the arms!  The mouth!  The everything!  Also, they're pretty large, with the central disk growing up to 5.5 inches (15 cm) across.  JUST THE DISK.  Did I mention they don't have blood?  And look like dendritic structures inside the brain, except they're mobile, huge and have regenerative limbs?

Here's a video to help drive home how...special...they are:



In case you didn't find that unsettling, let's also meet their cousins, the brittle stars!



And a final video, in honor of Halloween.  One of the defense/stress mechanisms of sea cucumbers (another echinoderm; while many cultures eat them, they are NOT sea vegetables, they are mobile organisms) is to violently expel parts of its respiratory organ out of its anus.  It is things like this that make me happy to be a human, for while I may cope with stress poorly, my reactions do not include violently crapping out my lungs. 

When they do this (called "evisceration" for obvious reasons), they may expel a nasty chemical soup that will hopefully take care of the predator...however, if you're keeping sea cucumbers in a tank, it may also kill all the other inhabitants in a charming process called "cuke nuke".  GAME OVER, PLEASE INSERT COIN AND TRY AGAIN.  They do grow these organs back, but depending on the violence of the evisceration, the cucumber may be injured in the process.

So, for your pleasure, here are some divers molesting a sea cucumber to get it to demonstrate this marvelous ability.  While I personally think molesting sea cucumbers is rather rude, evisceration evidently pretty normal for them.



Hope you enjoyed, have a Happy Halloween! 

1 comment:

  1. SCIENCE: BEST FOR HALLOWEEN.

    That sea cucumber is strangely adorable and scary at the same time. Also, fun exercise: try to apply radial symmetry to human beings. This is probably why I find the flag for the Isle of Man so creepy.

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