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Fontana del Tritone  (Gian Lorenzo Bernini ca.1624-1643, Piazza Barberini, Rome)

Fontana del Tritone
(Gian Lorenzo Bernini ca.1624-1643, Piazza Barberini, Rome)

Triton (the moon) and tritons (the gastropods) are named after…Triton, a Greek sea god who was the son of Poseidon (king of the sea) and his wife Amphitrite (herself a daughter of the ocean titans Nereus and Doris).  Triton was portrayed as a mighty merman who carries a musical conch with which he calms the seas…or whips them into a frenzy.

Triton1

Triton lived with his parents in a golden palace beneath the waves (according to Hesiod).  He has a few cameo appearances in classical mythology (most notably in the story of Jason and the Argonauts) but he is generally overshadowed by his mighty father.  In late antiquity and the Renaissance, Triton came to be a sort of progenitor of mermaids and mermen (a role which he occupies in Disney’s “animated film The Little Mermaid”).

Triton and Ariel (from "The Little Mermaid")

Triton and Ariel (from “The Little Mermaid”)

Geologists know that oceans and seas are indeed ever-changing and protean.  Whenever I think of Triton, I imagine how the oceans of the world will be entirely different in a few hundred million years (just as today’s oceans are no longer the Tethys or the Panthalassic Ocean).  Neptune’s reign will end and the oceans and seas will change–and yet they will really be the same great world-sea as they have been since the beginning.

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A Giant Triton (Charonia tritonis) on an Indonesian Reef

A Giant Triton (Charonia tritonis) on an Indonesian Reef

Yesterday this blog took us to the depths of space to explore the frozen ice-moon of Triton.  Today we atone for that cold voyage with a trip to the inviting tropical seas of the Indo-Pacific.  In these vibrant waters can be found one of the greatest living gastropods, a prince among predatory sea snails, the mighty Charonia tritonis, (commonly known as the giant triton or Triton’s trumpet).

A Giant Triton climbs over a pillow coral in Hawaii

A Giant Triton climbs over a pillow coral in Hawaii

Charonia tritonis grows to over half a meter (20 inches) in length: it is one of the largest living snails in the world (and it is not much smaller than the biggest extant snails). Equipped with a powerful muscular foot, acute senses (particularly smell), and an agile tentacle-like proboscis, the snails are formidable hunters.  Additionally they are protected from predators—even big fierce ones–by their beautiful spiral shells which are vibrantly colored orange, brown, yellow, and cream.  Of course such a shell would become a liability for the snail if an animal ever evolved which killed the snails in order to harvest the magnificent shells solely for their beauty (but what are the chances of that?).

A man sounds a blast on a triton shell--which has spiritual significance in Hawaii

A man sounds a blast on a triton shell–which has spiritual significance in Hawaii

Giant tritons hunt at night.  Their main prey are echinoderms—starfish, which can be large powerful and armored.  Fortunately the snails are not just equipped with powerful muscles and superior brains.  They also have salivary glands that produce sulfuric acid AND a chemical which paralyzes starfish.  The tritons find starfish—even big spiny poisonous starfish like the invasive and all-consuming crown-of-thorns which bedevils the reefs of the Indo-Pacific—then hold them down and inject saliva into them.  As the starfish dissolves from within, the snails rip them apart and feast!

A triton kills a crown of thorns

A triton kills a crown of thorns

Tritons have a specific gender—they are male or female.  They seek each other out for courtship and the female then lays a large clutch of eggs.  When the eggs hatch, the young snails become part of the oceanic plankton for a (poorly understood) time before developing into adults.  Triton shells are esteemed by many cultures as sacred musical instruments.  The shells themselves are collector’s items and are arguably better known then the formidable long-lived predators which make them.  Although the snails are not threatened with extinction as such, there are fewer and fewer really big adult ones (or even small ones) on today’s reefs. This is a real shame, since those same reefs are being devoured by the horrible crown-of-thorns. Hopefully a new generation of divers and wildlife enthusiasts will appreciate the triton on the reef and leave them to their invaluable hunting.  Resist the urge to buy the beautiful shells and help save the reefs of the Indo Pacific!

Charonia_tritonis_a1

Japanese Bonnet Snail (Phalium/Semicassis bisulcata)

Japanese Bonnet Snail (Phalium/Semicassis bisulcata)

The helmet and bonnet snails (Cassidae) are slow moving hunters which live along sandy coasts in the tropics and subtropics.  Depending on the species (of which tere are approximately 60), these sea snails live anywhere from the intertidal zone to a depth of 100 meters.  During the day they bury themselves in the sand and at night they emerge to hunt their favorite prey—echinoderms (particularly sea urchins).

A Horned Helmet (Cassis cornuta) from the Hawaii coast

A Horned Helmet (Cassis cornuta) from the Hawaii coast

Most of the Cassidae are large snails with big mantles and heavy, muscular foot. They see by means of two eyes located at the base of a single pair of head tentacles and they use an extensible tube for smelling.

A helmet snail closes in on a sea urchin (image from wannadivekona.com)

A helmet snail closes in on a sea urchin (image from wannadivekona.com)

When a helmet snail catches a tasty echinoderm, the snail immobilizes its prey by holding the smaller animal within its mighty foot and releasing a paralytic enzyme from its salivary gland (which prevents urchins from using their spikes in self-defense).  The snail has a sharpened radula (an organ which consists of a chitinous tongue-like strip covered with razor sharp teeth) and two proboscis glands which produce a secretion rich in sulfuric acid.  Using the combination of radula and acid, the helmet snail bores a hole in the echinoderm’s armored body and devours the creature from within!

Shells from the Cassidae family (from OuterBanksShells.com)

Shells from the Cassidae family (from OuterBanksShells.com)

The shells of helmet snails are frequently large and beautiful.  Shaped like a heavy helmet, these shells consist of dextral (right sided) coils which whorl outward from a tight spiral spire.  The snails are divided into males and females (unlike many mollusks which are hermaphrodites or swap genders) and the females lay large masses of hundreds of eggs which can either hatch into planktonic free swimmers or into miniature crawling snails—depending on the species.  Some Cassidae are prized by shell-hunters and artisans such as Cypraecassis rufa, a snail from the coast of Southeast Africa which is favored by cameo carvers.

Bullmouth Helmet Shell (Cypraecassis rufa) from the store "Evolution"

Bullmouth Helmet Shell (Cypraecassis rufa) from the store “Evolution”

Vishnu in glory

Vishnu in glory in Vaikuntha (with Lakshmi and Ananta-Shesha)

Vishnu is one of the supreme Vedic beings of Hinduism.  He is an all-powerful deity who sustains and protects the universe–indeed, all beings within the universe are part of him.  Vishnu is the past, present and future.  He creates, sustains, and ultimately destroys all aspects of existence.  The multiple avatars of Vishnu—worldly incarnations which he assumes to directly experience and affect existence—lie at the center of Hindu myth.  Vishnu has lived many lives as Varaha, Rama, Krishna, and Buddha (well, at least to some of the devout), and performed many heroic deeds but his true divine nature transcends human understanding.

vishnu

When not incarnated as an avatar (and slaying demons, seducing milkmaids, or explaining the Bhagavad Gita to Arjun), Vishnu dwells in an abode known as Vaikuntha which transcends the material universe.  Sometimes Vaikuntha is imagined as floating atop a sea of milk or suspended in the infinite blackness of space.  In this numinous cosmological state of being, Vishnu reclines with his consort Lakshmi, the Goddess of wealth, beauty, and prosperity. In his four arms he holds a great conch shell, a mace, a chakra, and a lotus (padmus) which may or may not be the universe itself.

Vishnu-Ananta

Most interestingly, in his ultimate aspect of godhood, Vishnu reclines on another supreme deity, Ananta-Shesa, the king of all nagas, who is simultaneously a dasa (servant) of Vishnu and an incarnation of Vishnu himself.  Ananta-Shesa is sometimes portrayed as a five or seven headed cobra, but he is most commonly imagined as a naga (snake spirit) with immense numbers of cobra heads. Each one of these snake heads supports a planet and all of the heads constantly sing praises to Lord Vishnu. In Hindu iconography the heads are typically topped with crowns (but maybe you should imagine exoplanets instead).

vishnuWhen Kalki–the final incarnation  of Vishnu–manifests himself and ends the Kali Yuga (the current fallen incarnation of the universe) Ananta-Shesha will be one of the only things left.  The great snake god is eternal and stands outside the eternal cycle of death and rebirth of the universe.

Vishnu_and_Lakshmi_on_Shesha_Naga,_ca_1870

Aplysia californica (The California Sea Hare)

Aplysia californica (The California Sea Hare)

Behold Aplysia californica–an extremely large sea slug which grazes on red algae along the California coast.  The mollusk is rarely found at depths deeper than 20 meters.  It grows to seventy-five cm (thirty inches) in length and weighs a whopping 7kg (15.4 lbs).  Aplysia californica belongs to a family of sea slugs known as the sea hares –so called because the two rhinophores (smelling organs) atop the creatures’ heads are fancifully said to resemble a rabbit’s ears.

Aplysia californica (photo by Chris Nelson)

Aplysia californica (photo by Chris Nelson)

Although this Pacific gastropod is interesting in its own right, the slug is of greatest importance to humankind as a research animal (like the regenerating axolotl).  Aplysia has only 20,000 neuron cells–as opposed to a human brain which contains between ten and a hundred billion–and the slug’s neurons are extremely large.  This allows neuroscientists to easily observe and assess physiological and molecular changes which take place in the cells when the slug learns something.  Aplysia research is thus at the cutting edge of neuroscience.  Nearly everything we know about the molecular basis of memory and learning started out as research with the humble gastropod.

A Cartoon of a Sea Hare Learning

A Cartoon of a Sea Hare Learning

A news piece on CNN today featured Dr. Eric Kandel of Columbia University who won the 2000 Nobel Prize in Medicine & Physiology for neural research (mainly on these slugs) and made immense headway on what is probably the great cellular biology mystery of our time.  It is a pleasure to see a science article on CNN online but it was also somewhat dismaying to see how many comments were basically “why are we wasting money on studying slugs?”  In case it is not self-evident why we are trying to discover the fundamental molecular mechanisms of memory and cognition, here is a brief and not-at-all comprehensive list.

Understanding these underlying biological processes would probably help us find therapy for neuro-degenerative disorders (such as Parkinson’s disease, multiple sclerosis, and Alzheimer’s disease).  It might also allow us to comprehend a number of psychiatric conditions, such as schizophrenia and depression.  At some point in the future, understanding the molecular basis of memories and thoughts might also allow for the engineering of some sort of bioimplant for the nervous system.  You could learn Sanscrit by popping a chip in your head or record your nightmares via wire!   Beyond such science fiction concepts, knowing about how the brain works is an end into itself—understanding the most complicated known structure in the universe is a necessary step to building structures of greater complexity.

brain-storm

Although perhaps the politically polemicized commenters who object to studying the sea hare actually reject the creature’s sex life–which is indeed somewhat at odds with traditional notions of romance and propriety.

edus826016Like all sea hares, Aplysia californica is a hermaphrodite with both male and female reproductive organs.  Because of its physiology it can (and does!) use both sets of organs simultaneously during mating. Multiple Aplysia have been known to form chains of more than 20 animals (somewhat like pop beads) where each animal simultaneously acts as a male and female at the same time with its fore and aft partners.  Copulation lasts for many hours (or sometimes for days). One can see how the creatures’ amorous predilections might not sit well with puritans and fundamentalists, however for providing a window into molecular neurophysiology we owe this gentle sea slug a big round of thanks.

"Take a bow! Hmm, somebody teach the slug to bow."

“Take a bow! Hmm, somebody teach the slug to bow.”

Adult Asian Small-clawed otters (Aonyx cinerea)

Otters (subfamily Lutrinae) are the aquatic branch of the splendid Mustelidae family which includes all sorts of highly successful predators like weasels, ferrets, polecats, otters, fishers, and wolverines.  We have already described the giant river otter of the Amazon, a magnificent apex predator which lives on anacondas and piranhas but there are also 12 other species of otters living throughout the Americas, Eurasia, and North Africa (and in the ocean).

European Otter (Lutra lutra)

All of the otters partake of the tremendous strength (and weakness) of the Mustelidae family.  They are ridiculously fast, powerful, and agile, but in order to keep up their swift lifestyles they have huge metabolic intake.  This means they must eat all of the time, and as predators their life is one endless hectic hunt.  Northern otters are at a particular disadvantage since they live in freezing rivers, lakes, and oceans.  In cold weather, European river otters have to eat 15% of their weight every day, while Sea otters must daily down an incredible 25% of their mass.  Fortunately a fast metabolism brings its own incredible reward: otters (like weasels and ferrets) seem to be effortlessly moving while everything else is standing still.

A group of sea otters (Enhydra lutris)

Otters eat a startling variety of prey.  Although fish is the staple of their diet they also opportunistically eat snakes, frogs, lizards, birds, eggs, small mammals, mollusks, crustaceans, and sundry other invertebrates.  Their need for calories keeps them from being too picky.  Despite their speedy metabolisms, otters live as long as dogs (and can survive even longer in captivity).  Different otters have different levels of sociability—the Oriental small clawed otters and the river otters are quite clannish and live in big playful groups.

Baby Asian Small-clawed otters (Aonyx cinerea)

In addition to being great hunters (and eaters) otters are famous for playing.  Their frolicksome antics are a joy to behold, so I found some video on Youtube, but be warned: the sound on my computer is broken so I have no idea what the narrator/soundtrack/music is like.  It might be slidewhistles or it might be 2 minutes and 56 second of the foulest curse words.  Maybe you should watch it on mute.

 

 

Perhaps because otters seem to appreciate life, people have a reverence for them (not that reverence stopped furriers from nearly driving several species extinct during the course of the past three centuries).  In the  the shapeshifting dwarf Otr prefers to spend his time as an otter until he is killed by the malicious trickster god Loki.  Loki is forced to cover the otter skin with treasure, but one whisker remains uncovered and so Loki was forced to part with his magic ring of power (which went on to wreak havoc, as magic ring inevitably do).  To Zoroastrians, the otter was reckoned to be truly pure–and thus sacred to Ahura Mazda, the uncreated god who represents the apogee of wisdom, light, and goodness in their pantheon.  So if, by bad luck, the evil dragon Ahriman happens to burn his way into this world and begins to destroy existence you might want to go be near some otters.  You know, even without the evil dragon, you should go spend time watching otters.  They’re just great animals.

The North American river otter (Lontra canadensis)

Clione or “sea angels” swimming in a Tokyo aquarium (Photo by REUTERS/Kimimasa Mayama)

In terms of taxonomical diversity the gastropods are second most diverse class of animals on Earth (outnumbered only by the teeming class Insecta of the other great invertebrate phylum Arthropoda).  This means that there are some deeply strange arthropods out there. While we traditionally think of gastropods as snails and slugs there are odd subcategories of these creatures, like the subject of today’s post, sea angels (of the clade Gymnosomata).

A “Sea Angel” (Clione limacina)

Sea angels consist of six different families of pelagic marine opisthobranch gastropod molluscs.  Gastropods are named for their famous foot (the name means “stomach-foot”–a misnomer since gastropods all have true stomachs elsewhere) however the name is even more inappropriate for sea angels.  In these free-smimming predators, the gastropod foot, so familiar to us as seen on snails, has evolved into a pair of delicate wings for swimming through the water. Sea angels are very small: the largest species only reach 5 cm (2 inches) in length and most varieties are much more miniscule.  They prey on other tiny creatures swimming among the plankton—particularly other smaller slower species of gelatinous mollusks.

A hunting sea angel (photo by Alexander Semenov)

Adult sea angels lack any sort of shell—which they discard when they metamorphose into adulthood.  Their feeding apparatuses can be strangely complicated—pseudoarms and tentacles which recall their cousins the cephalopods. Sea angels are numerous in the oceans but some scientists are concerned that the acidification of the world’s oceans will cause substantial problems for the tiny translucent gastropods.

Sea Angel (Platybrachium antarcticum)

Man O’ War (Photograph by Enrique Talledo)

The Portuguese man o’ war (Physalia physalis) is not a jellyfish, in fact it is not a discreet animal at all, but instead a siphonophore—a colonial medusoid made up of specialized animal polyps working together as an organism.   These siphonophores have stinging tentacles which typically measure 10 metres (30 ft) in length but can be up to 50 metres (165 ft) long.  Being stung by a man o’ war does not typically cause death, but sailors and mariners who have survived the experience assert that it taught them a new definition of agony.

Glaucus atlanticus

But the fearsome man o’ war is not the subject of this post.  Instead we are concentrating on the animal which feeds on the man ‘o war (as well as other siphonophores which drift in the great blue expanses of the open ocean).  One is inclined to imagine that men o’ war are eaten only by armored giants with impervious skins and great shearing beaks (and indeed the world’s largest turtles, the loggerheads, are the main predators of siphonophores), however another much less likely predator is out there in the open ocean gnawing away at the mighty stinging colonies.   Glaucus atlanticus, the blue sea slug, is a tiny shell-free mollusk which lives in the open ocean.  The little nudibranch only grows up to 3 cm in length but it hunts and eats a variety of large hydrozoans, pelagic mollusks, and siphonophores (including the man o’ war).

Glaucus atlanticus eating velella colony animal

Although not quite as gaudy as its lovely cousins from tropical coral reefs, Glaucus atlanticus is a pretty animal of pale grey, silver, and deep blue with delicate blue appendages radiating out from its six appendages.  The little mollusks live in temperate and tropical oceans worldwide. They float at the top of the water thanks to a swallowed air bubble stored in a special sack in their gastric cavity. Because of this flotation aid, the slug is able to cling upside down to the surface tension of the waves.  Since it is entirely immune to the venomous nematocysts of the man o’ war, the sea slug can store some of the man o’ wars venom for its own use.   The tendrils at the edge of Glaucus atlanticus’ body can produce an extremely potent sting (so it is best to leave the tiny creatures alone, if you happen to somehow come across them).

Glaucus atlanticus inshore

Each and every Glaucus atlanticus is a hermaphrodite with a complete set of sex organs for both genders.  Incapable of mating with themselves they ventrally (and thoroughly) embrace another blue sea slug during breeding, and both parties then produce strings of eggs.  The hatchling nudibranchs have a shell during their larval stages, but this vestige quickly disappears as they mature into hunters of the open ocean.

This blog has featured replicas of two ancient sailing ships–the Greek trireme Olympias and the Norwegian Viking ship Dragon King Harald—however the prettiest modern replica of an ancient ship is a reconstruction of a much older vessel.  The ship Min of the Desert was hand built by 4 men and 2 teenage boys in the modern Hamdi Lahma & Brothers shipyard in Rashid, Egypt (which was called Rosetta in classical times).  The builders used traditional tools and original techniques to craft the Min after a sea-going Egyptian trade ship from 3500 years ago.

Archaeologists know a great deal about the boats which sailed the Nile–since they have the actual ships (which were preserved in tombs in order that Pharaohs could sail in the next world).  However sea-faring ships were not preserved in the same way and only trace evidence from underwater archaeological sights survives.  To build the Min, the modern shipwrights looked to river ships from tombs for technique, but they looked at ancient Egyptian art for a design. A 3,500-year-old bas relief from the pharaoh Hatshepsut ‘s funerary temple at Deir el-Bahri near Thebes, provided the basic design for the Min of the Desert.

Bas-relief from the temple of Hatshepsut

The ships pictured on the bas relief were trade ships which participated in Hatshepsut ‘s trade expedition to Punt, which took place in the ninth year of her reign (Hatshepsut was a lady pharaoh who lived in the 15th century B.C. and reigned as the fifth pharaoh of the eighteenth dynasty). From the time of the old kingdom onward, Egyptians had launched expeditions to the land of Punt, a kingdom rich in gold, frankincense, myrrh, and exotic timber. Numerous ancient Egyptian sources mention Punt (which was a trade destination for the Egyptians for over a thousand years) but none actually mention where it is—apparently everyone back then just knew. The actual location has eluded Egyptologists for 150 years.  To get to Punt, ships were carried in pieces across the desert to the Red Sea port of Saww.  Then the vessels sailed on the Red Sea…to where? Modern day Somalia and Arabia are the best guesses, but the issue remains in doubt.

Detail of Bas Relief of Voyage to Punt (from the temple of Hatshepsut)

When completed Min of the Desert measured 20 meters (66 ft) long and nearly 5 meters (16 ft) wide with a cargo capacity of about 17 tons. Held together entirely by mortise-and-tenon joints, the ship proved to be surprisingly seaworthy and fast.  Sailors rowed the Min in to position to raise the sail (a labor which required substantial physical strength) and then traveled along at speeds between 5 and 9 knots.  The ship handled 25 knot winds and 3 meter swells with ease. The modern sailors were surprised by the excellence of the 3500 year old ship.

An Ogham Stone at Derrynane

Saint Patrick’s Day spirit is beginning to pervade the land and the mind turns to all things Hibernian.  Last week, Ferrebeekeeper investigated Leprechaun tattoos and, though visually interesting, that subject quickly turned dark and scary.  This week, we plunge into the green forests of ancient Celtic Ireland to pursue the roots of Ogham, the mysterious tree alphabet of the Druids.  Get out your golden sickles and put on your mistletoe haloes, the nature and origin of Ogham are shadowed by primeval mystery and this whole journey could easily veer off into the fantastic realms of pre-Christian myth.

To begin with the basics, Ogham was a runic alphabet from early medieval times which was in use throughout the lands ringing the Irish Sea, but which seems to have been most prevalent in Munster (Southern Ireland).  Ancient objects inscribed in Ogham are most commonly found in Kerry, Cork, and Waterford, but are also known in Wales, Scotland, the Orkney Isles, the Isle of Man, and the Devon coast.  Stone monuments inscribed in Ogham are usually written in Old Irish or an unknown Brythonic tongue—probably Pictish.  The alphabet seems to have been primarily used from the 4th century AD to the 8th century AD (although correct dates are a subject of contention).

Um, Ogham, I guess....

There are many historical theories explaining the origin of Ogham, but none are conclusive.  Some scholars hold that the script originated during the Roman conquest of Britain as a sort of non-Roman code language used between Celtic people.  Others assert that the language grew up as a means for denoting Celtic sounds—which the Roman alphabet is not well suited for—and became more complex and complete only as Christian scholars set up communities in Ireland. Wilder theories involve ancient primitive peoples as diverse as Mesolithic hunter-gatherers, the lost tribes of Israel, and the mysterious Sea People who destroyed Minoan palace civilization in the Mediterranean (please, please don’t tell my Irish history professor that I let you know about any of these hare-brained ideas).  My favorite mythical (as in “not-real”) story of the origin of Ogham involves the legendary Scythian king, Fenius Farsa, who invented the Gaelic language and then crafted Ogham out of scraps recovered from the fallen Tower of Babel (there’s more than a soupçon of world-famous Irish blarney in this folktale).

Brueghel's "Tower of Babel" (I never noticed the workmen wearing green eating potatoes in the left corner)

Whatever the actual origins of Ogham were, a large number of inscribed stones have been found in what were once Celtic lands.  Most of these were territorial markers and memorials—the oldest of which come from Ireland (although it is believed there was a heritage of inscribing the lines on sticks and bark which predated stone inscriptions).  Some scholars believe the Welsh, Manx, Scotish, British, and Orkadian Ogham stones date from Post-Roman Irish incursion/invasions.  Ancient tradition assigns the names of trees or shrubs to each of the letters of Ogham (although such a naming convention may only date from the tenth century).  A comprehensive glossary of letter names can be found here along with a translation of an ascetic Ogham joke (of sorts).

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