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Leopard nudibranch / Photo by John Williams
Nudibranchs are gastropod mollusks which live in the oceans worldwide from the polar regions to the tropics. The slugs live in virtually all depths and various species range from the shallow intertidal surf to depths of more than over 700m. Although the majority of nudibranchs are benthic creatures which crawl along the seafloor, some prefer other lives and float upside down under the oceans surface or swim in the water column.
Blue-tipped Nudibranch (Janolus Christus)
Nudibranchs lose their vestigial shell during a larval phase. To protect themselves they rely on toxins or unpleasant tasting chemicals which are advertised with extremely vivid colors. In order to enliven the gray winter months, here is a little parade of lovely nudibranchs. Enjoy!
Nudibranch by Hani Amir
Piggy Back Nudibranch M4 Cava.jpg (33601 bytes)
Piggyback Nudibranch (Risbecia Tryoni) Photo by Laurie Cava
from jaysdaysaway
Nudibranch (Nembrotha kubaryana)
Image: cosmicmache.blogspot.com
Image: cosmicmache.blogspot.com
Hopkin’s Rose Nudibranch (Hopkinsia rosacaea)
Nudibranch by Dermal Denticles
Nembrotha cristata
Ray Troll painting large amoonites for “Night of the Ammonites” exhibit at Seattle’s Burke Museum
One of my favorite living artists is not interested in the fatuous self-absorption and navel gazing which characterizes most contemporary artwork. Instead of falling in love with himself, Ray Troll fell in love with aquatic animals—and his art is a pun-filled paean to the astonishing diversity and complexity of life in Earth’s rivers, lakes, and oceans both in this epoch and in past geological ages. Although Troll’s vibrant biology themed art is humorous and fantastic, it also resonates at a deeper level. Themes of ecological devastation and the broad exploitation of the oceans are unflinchingly explored, as is the true nature of humankind. Troll (correctly) regards people as a sort of terrestrial fish descendant who still have the same aggressive territoriality, unending hunger, and crude drives that propelled our distant piscine forbears. This sounds deterministic and grim until one comprehends the high esteem which Troll holds for fish of all sorts. After looking at the beauty, grace, and power of his fish art, one feels honored to be included in the larger family (along with all the mammals, birds, reptiles, and amphibians which trace their roots back to fish-like tetrapod ancestors).
‘Crusin’ the Fossil Freeway’ by Ray Troll (the artist is visible on the driver’s side)
Troll is a favorite artist because he endeavors to understand paleontology, ecology, and biology and synthesize these extraordinary disciplines with broader human experience. The result is a whimsical and surreal mixture of creatures and concepts from different times and places rubbing elbows as though Hieronymous Bosch were having a happy daydream. Troll is a “popular” artist in that he makes a living by selling books, tee-shirts, and posters rather than swindling billionaire bankers into multi-million dollar single purchases, so you should check out his website. In keeping with the themes of Ferrebeekeeper, I have added a small gallery of his mollusk and catfish themed artwork (although such creatures are only featured in some of his paintings and drawings). Unfortunately the online sample images are rather small. If you want to see full resolution images you will have to buy his books and artwork (which is a worthwhile thing to do).
“The Encante”, (Ray Troll, 2004, colored pencil on paper, 11” x 30”)
The Encante is a paradisiacal underwater realm where shapeshifting river dolphins lure humans. The aquatic creatures are able to be themselves in this realm of magic and dance. Not only does Troll’s work feature the beauty of the Amazon and the otherworldly magical river dolphins, there are also a host of amazing catfish, including several armored catfish, and a giant bottomfeeder which has apparently developed an unfortunate taste for human flesh.
Got Ink? (Ray Troll)
Octopi Wall Street (Ray Troll)
Here are a handful of Troll’s pun-themed tee-shirt drawings involving amazing cephalopods. I like to imagine the populist octopus in battle with the fearsome vampire squid which is so emblematic of Goldman Sachs.
Night of the Ammonites (Ray Troll)
Finally, here is a naturalistic portrayal of how the ancient ammonites most likely came together to spawn on moonlit nights of the Paleozoic (such behavior is characteristic of the squids and cuttlefish alive today). The long-extinct cephalopods are portrayed with life and personality as though their quest to exist has immediate relevance to us today. Indeed–that might is Troll’s overarching artistic and philosophical point: life is a vividly complex web of relationships which knit together in the past, present, and the future.
Life around a Cold Seep
This week Ferrebeekeeper has been concentrating on the theme of discovering new life—a search which is very much ongoing even in today’s used-up overpopulated Anthropocene world. This concept has taken us to the mid levels of the ocean and the mountain jungles of Thailand and Vietnam to encounter species unknown (like this mystery sea slug, the tiny parasitoid wasp, and even a large hoofed mammal). However what is even more shocking is that our world features entire ecosystems rich with life that have only just been discovered.
A photograph of a pool of brine on the bottom of the ocean
A cold seep is an ecosystem on the bottom of the ocean formed around hydrocarbon-rich fluids which seep out of the earth and either “bubble up” or pool at the bottom of the ocean. The geography of such areas is alien to our perceptions: black pools of asphalt, barite chimneys, and undersea lakes of dense brine (which traps hydrocarbons and sulfites) are surrounded by otherworldly “reefs” of tube worms and benthic mollusks. The tube worms symbiotically partner with bacteria capable of “feeding” off the hydrocarbons while the mollusks filter feed on the archaeobacteria. Whole communities of grazers, scavengers, and predators then form around this base. Such communities are remarkable because they do not rely on photosynthesis as a source of energy and nutrients (much like more famous “black-smoker” ecosystems which are also chemotrophic ecosystems—but which form around hot volcanic vents). Cold seeps themselves were only discovered in 1983! Now that oceanographers know what to look for, cold seeps are being discovered in locations where we would never have looked for large complicated webs of life.
A Map of the collapsing Larsen Ice Sheet
In 2005, an oceanographic research team studying the seas once covered by the Larsen ice shelf (a melting shelf of ice located off the eastern side of the Antarctic Peninsula) discovered a cold seep community thriving in a glacial trough 850 meters (2,800 feet) beneath the ocean’s surface. The scientists found great mats of bacteria living on methane. These bacterial mats were in turn grazed on by strange bivalve mollusks and brittle sea stars. To quote EOS (a journal of the American Geophysics Union):
These results have implications for the discovery of life in extreme environments, including those found beneath the enormous extent of existing ice shelves and large lakes that lie beneath the Antarctic Ice Sheet. Because of its restricted conditions, the seafloor beneath ice shelves may provide a suitable, widespread habitat for chemotrophic systems; given this, there may be many more such habitats waiting to be discovered beneath existing ice shelves….The seafloor beneath Antarctica’s floatingice shelves covers more than 1.54 million square km [Drewry, 1983], an area of the same order of magnitude as the Amazon basin of Brazil or the Sahara desert.
So science is only just beginning to apprehend the sorts of biomes which are found across huge swaths of Earth. There are even more remote areas which are wholly unknown—like Lake Vostok, a subglacial lake wholly isolated from the rest of Earth (including the atmosphere) for 15 to 25 million years. As continental drift and the Antarctic Circumpolar Current froze Antarctica, Lake Vostok was trapped beneath 4,000 m (13,100 ft) of ice, and it has remained so until this year (when an intriguing but sloppy Russian drilling expedition means to pierce the lake). What scientists discover beneath the other ice dwindling shelves, and what the Russians find beneath the East Antarctic Ice Sheet will have broader implications for how we conceive of life on Earth–and beyond.
A watercolor painting by of chemotrophic life by Karen Jacobsen, an artist who has traveled to the bottom of the ocean via bathysphere to record her impressions!
Cast your imagination down to the bottom of the ocean—not at a beach or a bright coral reef just offshore, but the true ocean floor—the abyssal plains which cover much of Earth’s surface. Here vast flat swaths of mud lie in black silence. Only the occasional seamount or shipwreck breaks the monotony of plains as big as continents. Tides do not particularly affect the bottom of the ocean. The most violent storms do not perturb the waters. Even humankind’s restless activities, which have so much affected the rest of the planet, mean little here. At first it seems bleak, but soon enough you realize that life is everywhere here. There are spiderfish, lizardfish, deep sea octopuses, bizarre roving sea cucumbers, and all sorts of strange creatures, but we are not here for them. Instead we are concentrating on an inconspicuous worm-like animal. The tiny cylindrical creatures are only 5 cm (2 inches long) and they shimmer strangely when exposed to light. It would be reasonable to assume that they were worms or tiny sea cucumbers, but they are not. The benthic beasts are members of the aplacophora class of mollusks—the naked mollusks. They are presumed to be similar in appearance and nature to the basal mollusks from which the other classes of mollusks have evolved (although both fossil and molecular evidence is frustratingly exiguous). To look at aplacophorans is to see back to the Cambrian (540 million years ago) and to glimpse an even earlier era when the ancestors of the mollusks diverged from the annelids.
Two specimens of the aplacophoran Simrothiellidae (photographed by G. Rouse)
The aplacophoran shine because of tiny calcareous spicules embedded in their skin. There are about 320 known species split between two clades: the caudofoveates and solenogasters. To quote the University of California Museum of Paleontology website, “Caudofoveates are burrowers that feed on detritus and bottom-dwelling microorganisms, while solenogasters feed on cnidarians. Both groups have a radula and lack true nephridia.” There is an even more important distinction between the two different clades: whereas solenogasters are hermaphrodites, caudofoveates have two genders, and reproduce by external fertilization.
Epimenia australis (Photo by R. Willen)
The depths of the ocean are known to harbor animals which have vanished from the rest of the Earth long ago, and such is believed to be the case with aplacophorans. For a half billion years they have gone about their business in a part of the world which is resistant to outside change. The next time you fly across an ocean, imagine all of the naked mollusks in the muck at the very bottom and think about the vast amount of time they have been there.
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)
A very lovely photograph of an octopus kite by Nigel Bence
Ferrebeekeeper has written about actual flying squids which dart above the water waving their lateral fins to extend their gliding ability. But real squid are not the only cephalopods that one sees in the skies–especially around springtime. Two of the classical shapes for kites are squid & octopus shape. The squid’s finned oblong shape, and the octopus’ round shape are perfect for balance and for catching the wind. The dangling tentacles act perfectly as multiple tails. This spring has taken a cold gray turn—at least in New York, but while you are inside planning what to do during May, perhaps you should build some octopus and squid kites. Here is a little gallery of images from different kite festivals and kite makers around the world.
A Commercially available Octopus kite/kit
Like squids and octopuses, none of the kites I had when growing up ever lasted long (well none of the ones I actually flew). The beautiful range of mollusks suspended on the wind in the sky makes me wonder if I have any time to get out some dowels and crepe paper and build some more kites [sadly you do not have any such time—ed.]. As the soon as the weather clears up again, I hope you enjoy some kite flying!
A few weeks ago Ferrebeekeeper featured a post about belemnites, extinct cephalopods from the Mesozoic which teemed in immense schools through the reptile-haunted oceans of that bygone era. Yet belemnites were certainly not the only cephalopods which swam in the Mesozoic seas. Numerous shelled cephalopods—the ammonites—were widespread in every sort of marine habitat. Ammonites are personal favorites of mine so I am not going to write a comprehensive explanation/description of the subclass. Instead I wish to provide you with an idea of how big ammonites could get by providing a few pictures of large ammonite fossils which have been discovered. Imagine these monsters jetting through the water with huge tentacles and big intelligent eyes scanning for giant predatory reptiles and you will have a better idea of the Mesozoic Oceans!
This one is only .7 meters (two feet) in Diameter but it sure is pretty.
Odobenocetops as digitally rendered by the BBC for "Chased by Seamonsters"
This blog has featured posts concerning saber-toothed seals and saber-toothed marsupials but did you know that the oceans around South America once contained a saber-toothed whale? Odobenocetops lived during the Pliocene era (around 2.5 to 5 million years ago). Two similar species are known in the genus from fossils discovered in coastal Peru. An early member of the dolphin superfamily, Odobenocetops was probably more closely related to narwhals and belgugas then to modern dolphins and killer whales.
Measuring only a little longer than 2 meters (6 feet) in length, Odobenocetops was remarkable (at least among whales) for its flexible neck–which could turn 90 degrees. The powerful blunt snout of the endearing little whale suggests that it fed from beds of mollusks and other bottom dwelling shellfish, which it rasped from their shells with a muscular tongue. Additionally, the Odobenocetopsidae had echolocation abilities like modern dolphins–although probably not so amazingly precise, since the extinct whales’ echolocation melons were much smaller than those of living dolphins.
Odobenocetops feeding
Of course the most distinctive features of Odobenocetops were their long spiky teeth running parallel along their sides. Scientists speculate that these tusks could have been used to seek food or as a sensory organ–like the narwhal’s sensitive tusk. Perhaps male whales used their tusks to battle for females, like walruses do (although they seem awfully brittle for such battles). Some males had uneven tusks. The sole known skull of a male Odobenocetops leptodon features a right-hand tusk 1.2 m (4 ft.) long, while the left-hand tusk is only 25 cm (10 in.) long. Since this is the only male O. leptodon skull currently known, it is unclear whether such asymmetry was normal.
It is striking that the whales’ saber teeth were held next to the body and it makes one think that the whale did not execute many sharp turns. A humorous but somewhat sad cartoon which I found unattributed on the web demonstrates the potential drawbacks of the Odobenocetops’ striking saber toothed design.
Aww...the poor whale...
For Saint Valentine’s Day here is a collection of “sailor’s valentines”. These were ostensibly a form of nautical art—like scrimshaw–created by old sea dogs in the days of canvas and manilla. On the long voyages the grizzled sailors would tenderly glue shells together in wooden (particularly octagonal cases) to give to their family and sweethearts when they returned to port. There is something appealing about this picture–but seashells come from shore. Additionally one wonders how much craft space sailors were allowed in the age of wind.
A counter narrative has arisen that sailors would buy these shell designs from a merchant in Barbados who was responsible for most of the early examples. Once the idea became popular, artisans began to make the little seashell mosaics at home. To be honest, I can picture my great-grandmother at a table filled with shells and glue much more easily than I can sea Captain Haddock putting together something like this. Whatever the case, the carefully arranged shells create delicate and lovely little artworks. Even if they were not made by sailors or given at Valentine’s Day, I am repurposing them as a valentine to all of my readers!
To reiterate: Happy Valentine’s Day!
Sealife Mosaic from "the House of the Dancing Faun" in Pompeii (ca. 1st century AD)
So much of Roman artwork is lost. Except in remarkable circumstances, Roman paintings, textiles, and drawings were too fragile to survive the long centuries of neglect. Almost all are now long gone. Fortunately the Romans were masterful mosaic artists and mosaics are durable. Many mosaics concerning all sorts of aspects of classical life have lasted through the millennia. Some of these tile artworks present the loves of gods or the wars of men but quite a few are more humble and show the aftermath of a banquet or fishermen hauling in a day’s catch . Since Romans ate a huge amount of seafood, it is no surprise that many mosaics showcase mollusks of one sort of another. Here is a gallery of Roman mosaics featuring octopuses, squids, bivalves, or snails. I have tried to add as much information as I could but some of the photos I found were poorly labeled
Marine Life Mosaic from House viii in Pompeii demonstrating the vermiculatum technique (ca. 2nd century BC)
Detail of a Roman bath mosaic depicting a murex. (ca. late second to early first century BC)
Floor mosaic from "House of the Faun" Pompeii: Cat with bird, ducks, and sea life.
Ancient Roman Mosaic Prtraying Sealife from the British Museum
Triton with an octopus and squid (Forum Baths, Herculaneum)
Roman Mosaic of an Octopus
Modern mosaic makers were inspired by the Roman example and flamboyant cephalopods are a major theme of contemporary mosaics as well as ancient ones. Here are some modern octopus and squid mosaics for millionaires’ swimming pools, elementary schools, or even everyday bathrooms. Enjoy!
Modern copy of a Roman era mosaic from Milreu, Portugal
A Kraken for the bottom of a swimming pool (by Laurel Studios)
Octopus Mosaic for a public school
Contemporary Octopus Mosaic
A squid mosaic in downtown Pittsburgh, Pennsylvania
Octopus Mosaic from Seattle Country Day School
Navigation Mosaic by Mia Tavonatti
