Mimic Octopus at Aer_Parang, originally uploaded by Stephen Childs.

The fascinating Thaumoctopus mimicus, filmed at Aer Parang (Indonesia?).

We interrupt Plush Week to bring you this awesome video by the Monterey Bay Aquarium Research Institute (MBARI). I’m virtually certain that the first few are Humbolt Squid (Docidicus gigas), but can anyone identify the rest?

(Tip o’ the tentacles to Pharyngula and Deep-Sea News)

UPDATE!

In the comments, Linda Kuhnz from MBARI comes to the rescue. She says…

The squids featured in this video were filmed in Monterey Bay (except for the Piglet Squid, which was filmed in the Gulf of California) at depths ranging from 980 to 3,150 feet.

A) Black-eyed Squid (Gonatus)
B) Humboldt Squid (Doscidicus gigas)
C) Swordtail Squid (Chiroteuthis)
D) Market Squid (Doryteuthis opalescens)
E) Cockatoo Squid (Galiteuthis)
F) Swordtail Squid (Chiroteuthis)
G) Octopus Squid (Octopoteuthis)
H) Piglet Squid (Heliocranchia)
I) Swordtail Squid (Chiroteuthis)

Glow: Living Lights

Don’t miss the first-ever museum exhibition to explore the phenomenon of bioluminescence — an organism’s ability to produce its own light.

Visitors to Glow: Living Lights start their journey by investigating the chemical process that produces “cool” light. They then explore the world of light-producing terrestrial organisms like fireflies, glow worms and foxfire fungus before traveling on to the mid-ocean, where an estimated 90 percent of the animals produce light. Here visitors encounter alien-looking creatures like viper fish, which dangle a light lure to attract their next meal, and cookie cutter sharks, which earned their name from the cookie-size chunks of flesh they take out of unsuspecting prey in the dark. Visitors continue on to demonstrations of the interesting techniques and equipment used by scientists to study bioluminescence, and then explore the many benefits of this research — from helping to speed the study of cancer-fighting drugs to the detection of anthrax spores in public places.

The exhibit is open from 10 am–5 pm Monday–Saturday and noon–5 pm Sunday, with the last entry at 4 pm every day.

Tickets prices are: $7 Adults; $5 Seniors/Students; $4 Children (5–11); free to Members.

Although cephalopods aren’t specifically mentioned in the above description, they use an image of a biolumenescent squid on their site and their print ads for the exhibit, so I’m confident our glowy, tentacled friends will be included!

If you’ve never been to the NC Museum of Natural Sciences, I highly recommend it. Their permenent exhibits include a nearly complete mounted skelton of Cretaceous Theropod Acrocanthosaurus atokensis (aka, Acro, Terror of the South!), a specimen of the Cretaceous Ornithopod Thescelosaurus which was found with a fossilized heart (aka, Willo), and an impressive collection of mounted whale skeletons.

The museum is located at 11 West Jones St, Raleigh, NC. It’s open seven days a week and admisson is Free (except for special exhibits).

The episode is a little over 1 hour long, and I haven’t had a chance to listen to it yet. Of course, I have quite a bit of extra time on my hands these days (in theory at least), so I’m sure I can block out some time for one of my favorite topics!

You can download the episode (June 16, show 019) and read the show notes here.

Monster Talk is a skeptical look at the creatures of cryptozoology and folklore. Hosts Blake Smith, Ben Radford, and Dr. Karen Stollznow interview scientists and other experts about the science (or lack thereof) behind the word’s legendary beats.

You can subscribe to Monster Talk for free via RSS or iTunes.

First, we have some new research about the metabolism of Mesonychoteuthis hamiltoni, Sensational Squid #2;

National Geographic: “Colossal Squid a Soft, Sluggish Drifter”

Summary: A study published in the Journal of the Marine Biological Association of the United Kingdom finds that M. hamiltoni is not a ferocious hunter as often imagined, but rather a slow, passive ambush predator. The researchers measured the metabolic rates of smaller cold water squid species and scaled up the results to account for the size of the Colossal Squid. Their analysis indicates that the Colossal Squid has a very low metabolic rate, low energy requirements, and moves very slowly. The study team estimates that a single 11 pound fish can sustain a 1,100 pound squid for 200 days.

The next story is directly related to last week’s Argonaut video;

Wired Science: “Argonaut Octopus Mystery Solved”

Summary: In a study published in the Proceedings of the Royal Society B, biologists Julian Finn and Mark Norman (both of Museum Victoria, Melbourne, Australia) have found that female Argonauts use air bubbles trapped in their shell-like egg cases to control their buoyancy. When wild Argonauts lost the air bubble, they were observed quickly swimming to the surface to take in more air. They positioned their bodies within their cases to create an air-tight seal and then descended to a depth where the water pressure compressed the trapped air enough to achieve neutral buoyancy.

Parapuzosia seppenradensis. (replica), originally uploaded by muzina_shanghai.

I’m still in a paleontological mood after yesterday’s big news, so here is another big fossil…literally. Parapuzosia seppenradensis is desmoceratid ammonite from Late Cretaceous Germany, and it is the largest known ammonite species. An incomplete specimen found in 1895 had a diameter of 1.95 meters (~6 ft), and in life it is estimated to have been 2.55 meters (over 8 ft) across.

As big as P. seppenradensis was, it was by no means the largest prehistoric cephalopod. That honor goes to the giant Ordovician orthoconic (i.e. straight-shelled) nautiloid Cameroceras, which may have been as much 11 meters long (~36 ft). Of course that is the topic for another post…

[UPDATE: The image I originally used in this post seems to have been removed from Wikipedia Commons. Follow this link to see before and after reconstructions.]

The original Nectocaris specimen was discovered 100 years ago, but it wasn’t formally described until 1976. However, the phylogenetic identity of the two inch long creature remained uncertain. It seemed to have similarities to both arthropods and chordates, but didn’t clearly fit into any known group. In this new report, researchers Martin Smith and Jean-Bernard Caron examined 91 additional specimens and came to the conclusion that N. pteryx is a mollusk, specifically a primitive, non-mineralized (i.e. shell-less) cephalopod. This revelation pushes the origins of cephalopods back at least 30 million years.

As we can see from the above reconstruction, Nectocaris resembled a modern cuttlefish. It had a flat “kite-shaped” body with large lateral fins, but only a single pair of long, grasping tentacles. It had a pair of non-faceted eyes on short stalks and a large anterior funnel, suggesting that cephalopod jet-propulsion evolved very early on. The lack of a shell disproves a long held assumption that shell-lessness is a relatively recent adaptation. It now seems that cephalopods didn’t evolve shells until much later, most likely “in response to increased levels of competition and predation in the Late Cambrian.”

Nature 465: 469-472 “Primitive soft-bodied cephalopds from the Cambrian”

Architeuthis "princeps" Modified from Verrill, 1879

At long last, we come to the end of my countdown of Ten Sensational Squids, a close-up look at a few of my favorite Teuthids. The top spot belongs, of course, to the rock star of the squid world, the darling of cryptozoology, and the species that got me started on this whole cephalopod obsession in the first place, the one, the only, the Giant Squid!

1. Architeuthis dux (Giant Squid)

First officially recognized by science in 1857, the Giant Squid was considered for more than a century to be the world’s largest Invertebrate (both in length and mass), a title that now appears to belong instead to the Antarctic species Mesonychoteuthis hamiltoni, the Colossal Squid. However, this claim is not universally accepted, and some researchers still ascribe to Architeuthis a maximum total length of 18 meters…nearly 60 feet! The more conservative estimate, and one that has become commonly accepted in recent years, is that female Giant Squid max out at a mantle length of 2.25 m (a little over 7 ft) with a total length of 13 m (~43 ft), which falls just short of the estimated 14 m Colossal Squid. (Male Architeuthis, at a mere 10 m, are a bit smaller than their mates.)

So, what is the source of this size disparity? It all seems to go back to a single specimen which washed ashore at Thimble Trickle Bay, Newfoundland on November 2, 1877 (unless it was Nov 8, 1879). This particular squid was reported to have had 35 foot tentacles and a mantle and head which together measured an astounding 20 feet long! This means that just the body of this monster would have exceeded the total length of most Architeuthis specimens known to modern science! For comparison, the largest Giant Squid currently on display is an 8.62 m (28.3 ft) specimen caught off the Falkland Islands in 2004. Based on current data and the fact that the elastic nature of squid tissues (particularly their feeding tentacles) makes them notoriously difficult to measure accurately, the veracity of this 130 year old report is highly suspect.

There are several other unverified reports of similarly sized Giant Squids from the later part of the Eighteenth Century, and the cryptozoological literature contains accounts of even bigger squids. Could it be possible that 60 ft (or greater) Giant Squid actually do exist, lurking undetected in the ocean depths? Of course! In fact, that would be sweet as hell. However, the facts as we know them just don’t quite support such a claim. For further reading on this, I highly recommend you check out Cameron McCormick’s (aka, The Lord Geekington) pair of excellent articles that explore this issue in more depth.

Speaking of recommended reading, The Search For the Giant Squid: The Biology and Mythology of the World’s Most Elusive Sea Creature (Penguin, 1999) by Richard Ellis is still, despite being over ten years old at this point, the definitive guide to the history of humanity’s relationship with Architeuthis.

Bonavista Bay, Newfoundland specimen, circa 1981 (photo by derekkeats, from Flickr)

So now that we’ve tackled the size issue, what else to we know about the Giant Squid? They have long, narrow mantles, small ovoid fins, and huge eyes. Their arms and tentacles are lined with serrated suction cups. In life, they are a deep red color, but this is generally not retained in recovered specimens. Architeuthis is found world wide at depths of 300-1000 m (~984-3,280 ft). There may only be a single global species, A. dux, or possibly three, based on geographic distribution: A. dux (Atlantic), A. martensi (North Pacific), and A. sanctipauli (Southern). Wikipedia lists an additional five nominal species, and as many as 20 different species have been named over the years (many named from single, badly damaged specimens). They are predatory, feeding on fish and other, smaller squid, and, in turn, they themselves are preyed upon by Sperm Whales. If one assumes that Giant Squid make up a significant percentage of the whales’ diet, it would seem that are actually quite common, despite their uncanny ability to evade human detection. Because they are so seldom seen, however, little else is known about their behavior.

Melbourne Aquarium specimen, photo by Fir0002 (from Wikipedia)

Nearly all known Architeuthis specimens have been found either in the stomachs of Sperm Whales, washed up on shore, floating dead on the surface, or accidentally caught by deep-sea trawling. Sadly, none of these scenarios are kind to delicate soft tissues, and consequently, most specimens on display around the world are in pretty rough shape. The first photographs of a living adult Giant Squid were taken in 2002 on Goshiki Beach, Japan (the 13 ft individual was found at the surface and died soon after). It wouldn’t be until 2004 that a living Giant Squid was photographed in its natural habitat. Japanese researchers were able to lure a 26 ft Architeuthis to a baited line at a depth of 3,000 ft off Japan’s Ogasawara Islands. They took 500 pictures over the course of four hours, and you can see some of them at NationalGeographic.com. In 2006, the same research team filmed video of a live Giant Squid for the first time. Again using a baited line, the squid, an 11 ft female, was brought to the surface, as seen in this segment from Japanese television.

In October of last year (as reported right here on ISK), a professional underwater photographer captured the first pictures of Sperm Whales in the act of eating a Giant Squid. (You can see some of these amazing photos here.) This took place, yet again, in the waters off the Ogasawara Islands, further proving that Japan is the new center of modern Architeuthis research. Maybe one day soon someone will finally get footage of the legendary battle that is thought to take place when a hungry Sperm Whale sets his sights on an unsuspecting Giant Squid. This encounter has likely been mythologized, but it is mysteries like this, still unknown after nearly two centuries, that have helped make Architeuthis such a fixture in popular culture. Clearly, it is one of the Most Awesome Animals Ever.

PZ Myers posted this video of Argonauta argo (aka, the Greater Argonaut) on Pharyngula this morning, and I just had to follow suit.

See my article Eight Awesome Octopuses for more information on this fascinating pelagic cephalopod. (It’s octopus #4 on the list.)

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