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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.
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!
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).
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 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.
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.
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.
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).
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.
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.
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 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.
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.
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!
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
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!