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Flatfishes are an order (Pleuronectiformes) of predatory fish found in oceans worldwide.  There are over 700 distinct species in 11 separate (and sometimes very distinct) families.  Familiar flatfish include flounder, turbot, plaice, sole, and tonguefish (to name only a few).

Megrim-Stórkjafta-Lepidorhombus-Whiff

Flatfish undergo two great changes.  First they hatch out of an egg and become transparent tiny fry living among the zooplankton.  These baby flounder have an eye on each side of their heads–like all the other vertebrates.  Then, when they reach adolescence, they change a second time in a bizarre way.  One eye migrates over the young fish’s forehead.  Half of their body becomes pale and smooth.  To reach adulthood they abandon the vertebrate’s familiar symmetry and become strange asymmetric monsters.

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(An Adolescent Flounder, as its eyes migrate and it becomes opaque)

Very few animals have asymmetry of any sort (wrybills, hermit crabs) and even fewer are asymmetric in a systemic way (sponges).  Flatfish give up their symmetry on adulthood: they lose their ability to swim smoothly and see all around them…but, in turn, they gain prowess as lurkers. This helps them to hide in an ocean full of strife and peril. Equally importantly, it helps them to hunt.

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Flatfish are exceedingly gifted predators.  They thrive by eating unsuspecting fish, mollusks, arthropods, and worms which are scampering (or crawling… or propulsing?…or whatever) along the ocean bottom.  Pleuronectiformes are powerful, quick, agile, and invisible.  The horrifying hunting strategy of the flatfish is to lie perfectly still on the ocean bottom and gradually change color to match the substrate (they can match sand and pebbles and ripples and even chessboards).  Then, when a happy little shrimp minces endearingly along the ocean floor, suddenly the land itself opens a huge maw and SNAP! delicious shrimp supper for the stealthy flatfish.

flounder-fishing

For all of their gifts as predators, flounders are hardly the apex predators of their watery ecosystems.  They live in a world of super-predators: diving birds, grabby cephalopods, sharks, bigger fish, and cunning marine mammals. And that is to say nothing of all-consuming humankind: fisherfolk hunt for flounder with spears, traps, hooks, and nets.

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The flatfish, like most teleosts, are being fished to oblivion (even as their habitats rapidly change due to thermal fluctuation, invasive species, pollution, and acidification).  This troubles me for all sorts of reasons.  It represents the growing doom in the world ocean, from whence came all Earth life and upon which all life depends. We evolved from teleosts. Flounder are distant cousins.  Also I think they are beautiful in a bizarre way.  Their asymmetry strikes me as amazing and alien, yet somehow completely appropriate, practical, and compelling.

grill-flounder_975475d5adbf7e38Also, um, I like to eat flounder.

Anyway, I mention all of this because lately flatfish have supplanted doughnuts as the central fixation of my art.  They represent life to me…and so I have been drawing them by the dozen (and I am working on a book of intricate pen and ink flounder). Here is a teaser flounder.  More next week!

Russian flounder

Benevolent Flounder (Wayne Ferrebee, 2016, color pencil and ink)

 

 

Rock Ptarmigan (Lagopus muta) by Ólafur Larsen

Rock Ptarmigan (Lagopus muta) by Ólafur Larsen

The Rock Ptarmigan (Lagopus muta) is an Arctic gamebird from the grouse family. It lives in northern regions of Scotland, Scandinavia, Iceland, Greenland, Canada, Alaska, Russia, and China.  The birds are capable of surviving in extremely harsh winter conditions: indeed they do not fly south during the Arctic winter.  Instead they hunker down to last out the 24 hour long nights of bitter ice and cold.  In order to survive in permafrost landscapes, ptarmigans have water and wind proof feathers (which seal the chilling moisture away from their insulating down).  They also have feathered feet which act like snowshoes—their taxonomical name “Lagopus” comes from Greek roots meaning “hare foot”).  Ptarmigans are omnivores and they eat insects, seeds, berries, and leaves during the fleeting summers.  More remarkably, during the brutal winter months they can find food in the form of catkins, twigs, and buds buried beneath the snow and ice.

Rock Ptarmigan (Lagopus muta)

Rock Ptarmigan (Lagopus muta)

Not only are ptarmigans adapted to the cold, they are also astonishing masters of camouflage.  In winter they can fledge to become completely white.  In spring and fall the birds are white with black and gray blotches.  During the summer, the birds’ plumage becomes brown and yellow so they can blend in with the gorse and lichen. The following two pictures of brooding mothers should illustrate this point: the mama ptarmigans are hard to find even though they are pretty much the only things in the pictures!

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In spring male ptarmigans find a mate by emitting a guttural croak (although there is also a correlation between the size of a male’s comb and his testosterone level).  Females lay up to six eggs. Even in the egg, ptarmigans are masters of being inconspicuous.  Their eggs are stippled with spots and specks in order to blend in seamlessly with the rocks and tundra for the brief moments that ptarmigans are not sitting their nests.

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During the last ice age, the rock ptarmigan had an even wider range (which is astonishing, considering how widespread the birds are today).  Ptarmigans are a beautiful and timeless emblem of the north. Vikings carved the birds on knife hilts and the creatures are also a mainstay of Sami and Inuit art.

A bronze ptarmigan charm made by the Sami

A bronze ptarmigan charm made by the Sami

Felis silvestris lybica

Felis silvestris lybica


Aww! Wook at the wittle puddy-tat… Argh! Wait, that isn’t a puddy cat at all, it is actually Felis silvestris lybica, the African wildcat, a formidable crepuscular predator which ranges across the Sahara and Sahal up through the Arabian Peninsula and around the Caspian Sea. Although they are remarkable hunters, African wildcats are not large—males measure 46–57 cm (18–22 in) in head-to-body length (discounting the elegant tail) and weigh from 3.2 to 4.5 kg (7 to 10 lbs). Using stealth, speed, retractable claws, and athletic lunges, the wildcats hunt and kill everything smaller than themselves: small mammals are their main prey but cats also kill birds, reptiles, insects, amphibians, and miscellaneous arthropods. African wildcats hunt mostly at dawn and dusk, but thanks to incredibly keen senses, they can also hunt at day or night.
An African wildcat executes an insane flip while hunting doves

An African wildcat executes an insane flip while hunting doves


The senses of the African wildcat are truly astonishing. Their large vertically slitted eyes are extremely efficient in brightest day or in the faintest light (thanks partly to the tapetum lucidum—a layer of reflective cells at the back of the eye which reflects light back into the photoreceptors). Wildcat hearing is among the best in the animal kingdom—they can hear many ultrasonic noises inaudible to humans and dogs (cats developed this sense because many rodents and insects communicate with such noises). Their large mobile ears further augment their acute hearing. Although they do not have the unbelievable noses of dogs or wolves, wildcats have an amazing sense of smell which is estimated to be 14 times more acute than a human’s. Additionally, their heads (and particularly their faces) are covered with vibrissae (whiskers) to help wildcats sense vibrations and navigate in tight pitch black spaces.
African wildcat close-up

African wildcat close-up


As well as keen senses, African wildcats possess other features which help them fit into their harsh arid environment. They have striped stippled coats which are the color of rocks, dry grass, and earth—so they blend in to most environments effortlessly (although they tend to have lighter colored bellies). Living in vast deserts, African wildcats have shockingly efficient kidneys. The animals can live without water on the fluid from prey animals. If necessary, they can rehydrate with seawater. They can also survive extremely hot temperatures and do not show discomfort until 52 °C (126 °F).
African wildcat kitten

African wildcat kitten


Felis silvestris lybica is actually one of several subspecies of old world wildcat Felis silvestris which ranges across all of Europe, Africa, and Asia. Wildcats are very, very versatile, resilient, and effective predators, yet all of the subspecies of wildcat are gradually losing their genetic diversity except for the African wild cat. This is because of interbreeding with the domestic cat Felis silvestris catus. As you have probably gathered by now, domestic cats descend directly from a handful of African wildcats which were domesticated in the Fertile Crescent between 10,000 and 9,000 years ago when humans first became grain farmers. The first domestic cat was found buried in a Neolithic grave in Cyprus which dates back to 9,500 years ago. The wildcats (Felis silvestris) are all fully fertile when breeding across species, so some of the differences between the wildcat and the domestic cat are fairly arbitrary.
Eek, there is an African wildcat in my living room! Wait, that's my beloved housepet Sepia. You can tell by, um, the white bib and gloves...I guess?

Eek, there is an African wildcat in my living room! Wait, that’s my beloved housepet Sepia. You can tell by, um, the white bib and gloves…I guess?

Mountbatten Pink

Mountbatten Pink

Mountbatten pink is a color invented by and named after Admiral of the Fleet Louis Francis Albert Victor Nicholas Mountbatten (1900-1979), the 1st Earl Mountbatten of Burma, KG, GCB, OM, GCSI, GCIE, GCVO, DSO, PC, FRS, and the last Royal viceroy of India.  Mountbatten was a nobleman and a Royal Navy officer (as you could probably tell from his rank and title there).  In 1940 he was escorting a convoy carrying vital war supplies, when he noticed that one ship would constantly vanish from vision at twilight.  This phantom ship was still painted a strange grayish pink color from pre-war days.  Mountbatten became convinced that the pink was an ideal camouflage color and he had all of the destroyers of the Fifth Destroyer flotilla painted in the same shade (which not surprisingly came to be identified with him).

A Model of the HMS Kelly built by Ian Ruscoe

A Model of the HMS Kelly built by Ian Ruscoe

Mountbatten pink was a mixture of medium gray with a small amount of Venetian red.  The resultant neutral pink mimicked ocean and atmospheric colors of dawn and dusk.   Additionally, the German navy used pink marker dye to identify their shells, so Mountbatten pink ships often threw off spotters who were unable to tell ship from clouds of smoke (at least according to some Naval historians). One cruiser, the HMS Kenya, was even nicknamed the Pink Lady because of its color and panache.

Mountbatten pink (top) versus USN 5-N Navy blue (bottom)

Mountbatten pink (top) versus USN 5-N Navy blue (bottom)

Other British captains also painted their ships in Mountbatten pink (or used it as a component of the dazzle camouflage) either because of its effectiveness as battle camouflage, or to suck up to Lord Mountbatten, or out of genuine fondness for the surprisingly attractive lavender-pink, however the color had a critical flaw which ultimately caused the Royal navy to abandon it.  Although Mountbatten pink blended into the offing at dawn and dusk, it stood out against the ocean at midday.   By 1942 the color was phased out for large ships (although some smaller ships still had the color for a while).   Most photos and films of the day were black and white.  Imagine that some of the grim British fighting ships engaged in life & death fire fights with the Germans were actually pink!

A freighter with a WWII era dazzle paint scheme based around Mountbatten pink.  Is it just me, or does it look ready for an 80s installation?

A freighter with a WWII era dazzle paint scheme based around Mountbatten pink. Is it just me, or does it look ready for an 80s installation?

The Frogmouth Catfish (Chaca chaca)

I have always liked looking at underwater ambush predators like wobbegongs, wolf fish, stargazers, and frogfish. There is something appealing about the way that a pile of pebbles will suddenly resolve into a wide toothy mouth with little pebble eyes.  In freshwater environments from Nepal down through India, Myanmar, Bangladesh, and into Indonesia, the niche for highly camouflaged bottom predators is filled by Chaco Chaco, the frogmouth catfish.

 

The Frogmouth Catfish (Chaca chaca) photographed by K.Dreymann

The frogmouth catfish grows to a size of 8 inches (20 centimeters) and feeds on tiny shrimp and minnows.  The animal is mostly head and can swallow creatures nearly as large as itself.  Although the frogmouth catfish is already camouflaged, it prefers to bury itself in the mud or sand so that only its tiny black eyes protrude from the substrate.

 

The closely related Chaca bangkanensis

The catfish are extremely committed to their camouflage and even when captured they will not move (although they growl menacingly when removed from the water).  When kept in aquariums they rapidly raise the acidity of the tank which suggests that they either have potent gastric juices (for digesting large prey) or they might emit an unpleasant taste.      Aquarium keepers sometimes keep the little predatory catfish in tanks which appear to be empty except for a blank spot of mud.  The frogmouth catfish will only accept live food.  Here is a video of one eating some shrimp!

The Green vine snake (Ahaetulla nasuta)

The green vine snake (Ahaetulla nasuta) looks so ridiculously wicked and serpentine that it almost doesn’t look like an actual l snake but instead resembles an animated snake from a lurid 80’s cartoon.  Ahaetulla nasuta is mildly toxic and feeds on lizards and tree frogs which it catches by means of stealth and camouflage.  Native to most of southern India, the snakes are diurnal and arboreal.  Their great specialization is imitating tangled green vines, a feat which they pull off so successfully that most people never notice them, however, when startled they are capable of changing their color from bright green (which blends with the jungle) to a checkered black and white warning pattern.  In duress they also gape open wicked smiles to threaten off potential predators.  The snakes are viviparous and have astonished zookeepers by giving birth after being alone for years. It remains a matter of herpetological dispute as to whether the female snake is able to delay fertilization within her body for extremely long periods of time or whether she is capable of parthenogenesis (a rare but not unheard of trait among snakes).

The Green vine snake (Ahaetulla nasuta) displaying a threat posture. Photo bySandilya Theuerkauf

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.

Common cuttlefish - Sepia officinalis (photo by David Nicholson)

When I was a child, my family went to the invertebrate house in Washington, DC.  Upon entering the building, there was a very beautiful aquarium which contained the most alien creature I have ever encountered.  It was a beautiful glistening red…and then it instantly changed color to bright white with pale dun spots.  Next the strange being sank through the water column and changed color and texture. Its smooth skin knotted up into ropey bumps.  The speckled white tuned to wavy deep brown lines.  Intelligent eyes with W-shaped pupils regarded me from what suddenly seemed to be a hunk of rock. I had encountered my first live cuttlefish.  In fact there were two in the tank, as I discovered when a patch of unremarkable sand changed shape and color and jetted to the surface while flashing rainbow colors.  They were worked up because they were about to be fed and, when eating their suppers, the cuttlefish put on a particularly good show.  They changed color like digital screens and waved their eight arms about and then ZAP!  elongated feeding tentacles shot out from under their mantles to grab the anchovies from across the length of the tank. Then they rocketed around with uncanny torpedo speed.

Cuttlefish by Doug Deep

Cuttlefish are cephalopods like octopuses, argonauts, squid, and nautiluses.  Across the long ages they have descended from those magnificent nautiloids and othocones who ruled the world during the Ordovician era.  Cuttlefish are one of the most intelligent invertebrates: their brains make up a substantial portion of their body mass, and their behavior when hunting, hiding, and courting is complex. The unusually shaped eyes of the cuttlefish are among the finest in the animal kingdom.  Their blood makes use of copper rather than iron to fix oxygen so it runs green.  All cuttlefish possess poisons in their saliva.  In fact the Pfeffer’s Flamboyant Cuttlefish is as toxic as the Blue-ringed octopus.

Camoflaged Cuttlefish

But why am I talking about these extraordinary mollusks during a week devoted to blogging about color? First of all cuttlefish are “the chameleons of the sea.” As I observed at the zoo, they can change color with a speed and facility unrivaled by any other creature. They use their mastery of color to camouflage themselves, to hunt, and to communicate with each other.  The animal’s existence literally hinges around the color-changing chromatophores in their skin. But the association of cuttlefish and color doesn’t stop there. Cuttlefish produce a dense ink which they squirt into the ocean to disguise their movements when frightened. This sepia ink, collected from the ink-sacks of common cuttlefish destined for the table, was prized for writing and for drawing during the classical era.  Many of the great histories and literary masterpieces of Greco-Roman thought were first penned in sepia ink. Although other inks took the place of sepia for writing, it maintained its place in the artist’s studio up until the late nineteenth century when it was supplanted by synthetic pigments.

sketches for "The Last Supper" (Leonardo da Vinci, 1495, sepia ink on paper)

This means that many of the masterpieces of draftsmanship were also created with sepia ink.  A particularly effective and pleasing style was to sketch something in watered down sepia washes and finish the details with black india ink. Like chartreuse, magenta, and vermilion, the name sepia itself has become synonymous with a color.  This reddish brown is famous in old masters pen-and-ink drawings, antique photos, and memory-hazed movie flashbacks.  Not only has this ink provided some of the most beautiful drawings in history, recent studies have shown that cephalopod ink is toxic to certain cells—particularly tumor cells, so we may not have written the last concerning sepia ink.

Giant Grave by the Sea (Caspar David Friedrich, 1806-1807, sepia wash and graphite on paper)

A Brown Creeper beautifully photographed by Tom Munson

The other day I was outside enjoying the garden when I noticed that a piece of bark was hopping up and down the fence in a peculiar spiral pattern.  When I looked more closely, I realized that it was not bark at all, but an amazingly camouflaged hunter—the brown creeper (Certhia Americana).  This tiny North American songbird lives in deciduous and conifer forests, wooded meadows, and even in towns with sufficient tree cover (like Brooklyn, apparently!).  Brown creepers range from the southwest United States up to the Canadian provinces…even up to southern Alaska, but I’ve never seen one before (or probably I have, I just never realized it was a bird).  The pattern of its feathers, which looked so random and wood-like was actually quite beautiful and subtle when the bird was seen in the real world.  I have included some professional photos because mine didn’t come out.  The brown creeper also had an endearing little pale belly.

The brown creeper's call (does anyone have a flute or a harpsichord?)

The little bird acted much like a nuthatch (of which I am greatly fond) making short rapid hops up and down the aging wood of the garden fence.  It was clearly looking for tasty insects with its sharp curved beak and I believe it caught quite a few of the pests.  Then in a flash it was gone.  I’m used to the popular songbirds or the northeast, but I have never noticed the brown creeper and I found it rather touching.  Has anyone else seen these around here (or anywhere else)?

Brown Creeper (another amazing photo--this one by John Brierley)

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