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The mighty lion is clearly the king of beasts…or is he?  For your holiday pleasure, here is a gallery of octopuses wearing crowns.  Octopuses have short lives and they do not grow to immense sizes, but they are extremely intelligent.  All of the regal tentacles below put me in mind of the Ordovician, a geological age when mollusks (in the form of giant cephalopods) truly were the kings of the animal world.

A Young Lady with an Octopus wearing a Crown

A Young Lady with an Octopus wearing a Crown

A tattoo of an octopus wearing a crown and bearing a trident

A tattoo of an octopus wearing a crown and bearing a trident

A poster of an octopus wearing a crown by Octopus Wearing Crown by Pop Ink - CSA Images

A poster of an octopus wearing a crown by Octopus Wearing Crown by Pop Ink – CSA Images

An tiny tattoo of an octopus wearing a crown

An tiny tattoo of an octopus wearing a crown (Sidney Collins)

A rhinestone octopus wearing a crown (jewelry pendant)

A rhinestone octopus wearing a crown (jewelry pendant)

An Octopus Crown Indicolite Crystal European Bead (whatever that is)

An Octopus Crown Indicolite Crystal European Bead (whatever that is)

A tattoo of a crowned octopus collecting shells (by Jason Stephan)

A tattoo of a crowned octopus collecting shells (by Jason Stephan)

A sweater necklace

A sweater necklace

Retro hand drawn graphics of an octopus wearing a royal crown (from vector graphics)

Retro hand drawn graphics of an octopus wearing a royal crown (from vector graphics)

Decorative art Mixed Media Digital Illustration of an Octopus with golden crown (by Cocodeparis on Etsy)

Decorative art Mixed Media Digital Illustration of an Octopus with golden crown (by Cocodeparis on Etsy)

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An Adult Female Blanket Octopus

“Blanket octopus” sounds like an endearing nursery game, but the blanket octopuses are actually pelagic hunters which have adapted to living in the ultra-competitive environment of the open ocean.  There are four species of blanket octopuses (Tremoctopus) which can be found ranging from the surface to medium depths of open tropical and subtropical seas worldwide.  Because they often live far from any land, some of the methods which other octopuses use to escape predators do not work very well for them.  Fortunately Blanket octopuses have adapted in their own unique bag of tricks.

An Adult Female Blanket Octopus

Blanket octopuses are named after the distinctive appearance of adult female octopuses which grow long transparent/translucent webs between their dorsal and dorsolateral arms.  Blanket octopuses use these webs as nets for hunting fish, but they can also unfurl and darken their nets in order to appear much larger than they actually are.  Since blanket octopuses do not produce ink and can not camouflage themselves as rocks, coral, or sand, they rely heavily on their blankets.  As a last resort they can jettison the blankets as a decoy and jet away while the confused predator attacks the highly visible membranes.

Blanket octopuses exhibit extreme sexual dimorphism.  Whereas the female octopus can grow up to 2 meters (6 feet) in length, the male octopus is puny and does not grown longer than a few centimeters (1 to 2 inches).  Males store their sperm in a modified quasi-sentient third right arm, known as a hectocotylus.  During mating this arm detaches itself and crawls into the female’s reproductive vent.  As soon as the hectocotylus is detached the male becomes unnecessary and dies.

Male Blanket Octopus

Tiny males and immature females do not have blankets, but they utilize another trick to protect themselves.  Because they hunt jellyfish and other hydrozoans, the little octopuses are immune to the potent venom of the Portuguese man o’war.  The octopuses tear off stinging tentacles from the man o’war and wield them in their tentacles like little whips to ward off predators.

An amazing illustration of a blanket octopus sheltering in a Portuguese man o’war’s tentacles

Woodblock prints of ages past show giant octopuses ripping apart boats and feasting on sailors like popcorn.  These artifacts of ancient sea-lore make for rousing images, but they are quite wrong:  octopuses are fierce and cunning hunters but they present little danger to humans—with a noteworthy exception.  The truly dangerous octopuses are not giant monsters (perhaps the artists of yesteryear were thinking of the mighty giant squid?) but rather tiny jewel-like beauties from the genus Hapalochlaena which includes only three or four species.  Known as blue-ring octopuses the tiny creatures swim in tide pools and shallows of the Indo-Pacific Ocean from Japan down to Australia (where they are most prevalent).  Blue-ringed octopuses live on shrimp, crabs, minnows, and horseshoe crabs.  They are tremendous hunters who use camouflage, stealth, and guile to catch their prey.  However, these tools pale before their greatest weapon: the little octopuses are among the most poisonous creatures on planet Earth.

(photo by Aluki from Flickr)

Like the flamboyant cuttlefish, the blue-ringed octopus does not like to bite without giving warning but advertises its toxicity with vivid coloration.  The octopus can conceal itself with tremendous prowess however, as soon as it becomes aware of a predator or some other threat, it dials up its coloration changing from muted reef tones to brilliant yellow with iridescent blue rings.  If you see something like this in the ocean, for heaven’s sake don’t touch it.  The octopus’s warning colors let ocean predators know to leave it alone but immediately attract humankind’s magpie urge to grab shiny things.  Although blue-ringed octopuses are good natured and have been known not to bite people who were provoking them rather intensely, their bites have caused more than seventy recorded fatalities in Australia. The octopus has a tiny beak and often a victim does not realize they have been bitten until they began to fall into paralysis and their respiration starts to fail.

Argh, I said don't touch it

The venom of the blue ringed octopus is a complicated pharmacological cocktail which includes tetrodotoxin, 5-hydroxytryptamine, hyaluronidase, tyramine, histamine, tryptamine, octopamine, taurine, acetylcholine, and dopamine. The most active ingredient tetrodotoxin blocks the sodium channels which conducting sodium ions (Na+) through a cell’s plasma membrane.  This causes total paralysis for the octopus victim, however if clever and persistent rescuers are present at the time of the bite they can rescue the unfortunate soul with continuous artificial respiration.  This is no small matter as bite victims are often rendered completely unresponsive by the paralytic victim.  Although completely conscious they are unable to communicate in any way or even breathe.  If artificial respiration is initiated immediately and continued until the body can metabolize and eliminate the toxin, bite victims can survive (although it sounds like rather an ordeal).

Blue ringed octopuses are tender and solicitous mothers.  The mother octopus lays a clutch of approximately 50 eggs in autumn which she incubates beneath her arms for about six months (during which time she is unable to eat).  When the eggs hatch, the mother octopus dies. The baby octopuses reach sexual maturity in about a year.  Despite their cleverness and beauty, the animals are as ephemeral as they are deadly.

Under its mother's watchful eye a baby southern blue-ringed octopus (Hapalochlaena maculosa) emerges from its egg.

Stauroteuthis syrtensis (photo by David Shale and Claire Nouvian)

One of the reasons I chose mollusks as a topic is to illustrate how diverse life on our own planet is. The mollusks are an insanely heterogeneous phylum of creatures and they have been successful around the globe for the last 540 million years (at least). Even today in the ultracompetitive Holocene world, mollusks thrive just about everywhere.  To illustrate this point I am showcasing the enigmatic deep water octopus Stauroteuthis, of which two species are currently known.  These octopuses are only found more than 700 meters underwater in the Atlantic Ocean.  Although they are most common around 2 kilometers beneath the surface the creatures have been spotted as far as 4 kilometers down.  The Stauroteuthids are small benthopelagic octopuses (they are free-swimming but live in close proximity to the ocean floor).

(photo by David Shale)

The Tree of Life Web Project gives us the following overview of Stauroteuthid morphology:

Stauroteuthids are peculiar, gelatinous cirrates with a mantle opening that forms a complete tube around the funnel. They also have peculiar gills and internal shells and a large web that is nearly equally developed between all arms. When observed from submersibles, this octopod commonly has its arms and web formed into a bell-shape (bell-shape posture). Sometimes when the octopod is disturbed, it will inflate the web and draw the arms together at their tips to form a “balloon” with the arms and web (balloon posture). These postures are thought to be involved in feeding and/or defense.

That is nearly all we know about them—it is difficult to study creatures which live 2 kilometers underwater. However I have left out the most exciting fact: the Stauroteuthids are bioluminescent.  Certain muscle cells around the suckers have been replaced with photophores which allow the Stauroteuthid octopuses to light up their eight legs like plane runways.  The purpose of this luminescence is unknown but it is believed to be for predatory purposes (the lights are thought to direct prey to the octopus’ beak). Possibly the lights also help the octopuses to find and communicate with mates.

Bioluminescent Suckers (photo by ORCA)


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