Cloud watchers

I've always had a fascination for the weather.  Especially violent weather; if I hadn't become a mild-mannered high school biology teacher, I'd have been a tornado chaser.  One of my favorite movies is Twister, and yes, I'm well aware of how ridiculous it is, but still.  Who didn't cheer when the Bad Meteorologist got smashed to smithereens, and the Good Meteorologist and his wife survived and decided they were still in love?

*looks around*

*silence*

Okay, maybe it was just me.  But still.  There's something compelling about weather, which is why I frequently give my wife urgently-needed updates about frontal systems in South Dakota.  Like everyone does, right?

*looks around*

*silence*

Anyhow, having been a weather-watcher for years, I was absolutely flabbergasted to find out that recently, the powers-that-be in the meteorological world have added twelve new types of clouds to the International Cloud Atlas.  Which is a book I didn't even know existed.  I mean, I've known since I was a kid and got a copy of The Golden Guide to Weather that there were different sorts of clouds, classed by height, shape, density, and pattern (if any) -- with wonderful names like altostratus and cirrus and mammatocumulus.  It honestly never occurred to me, though, that there was an entire atlas devoted to them, much less that there might be new ones.  After all, people have been watching the skies for millennia, not to mention describing it and drawing pictures of it.  How could they see anything truly new?

Well, it turns out that some of the new ones only form under really specific conditions.  Take, for example, one of the newly-classified cloud types, named cavum, sometimes known as a "hole-punch cloud" or a "fallstreak hole."  This occurs in an altocumulus cloud bank, when something causes sudden evaporation in a region, leaving behind a hole through which you can see the blue sky.  It's sometimes triggered by an airplane or even a meteor.

A cavum formation in Austria in 2008 [Image licensed under the Creative Commons H. Raab (User:Vesta), HolePunchCloud, CC BY-SA 3.0]

Another is the volutus, or "roll cloud," often associated with windy weather near bodies of water, and thought to be caused by a soliton wave -- a single, stable standing wave front:

A volutus cloud, Punta del Este, Maldonado, Uruguay, 2009 [Image licensed under the Creative Commons Daniela Mirner Eberl, Roll-cloud, CC BY-SA 3.0]

Another new one is the murus cloud, or "wall cloud."  Although this one has been seen many times, especially if you live in the midwestern United States, it just recently received its own nomenclature.  It's a part of a cumulonimbus formation -- the kind of cloud that gives rise to thunderstorms and tornadoes -- and results from an abrupt lowering of the cloud base.  This indicates the area of strongest updraft, which is why murus clouds are a good indication that it's time to head to the storm cellar.

A murus cloud near Miami, Texas, 1980 [Image is in the Public Domain courtesy of the National Oceanographic and Atmospheric Administration]

One last one is the asperitas formation, which has an undulating, underwater appearance.  While they look threatening, they're more often seen after a thunderstorm has passed, and usually dissipate quickly without any further violent weather.

Asperitas clouds over Talinn, Estonia, 2009 [Image licensed under the Creative Commons Ave Maria Mõistlik, Beautiful clouds, CC BY-SA 3.0]

Anyhow, I was really surprised to hear that those only recently got their own official classification.  I guess it just goes to show that there is still a lot to be learned from the things we look at every day.  Speaking of which, it's time for me to check the NOAA forecast site and see about those frontal systems in South Dakota.  Carol is waiting for her update.  You know how it goes.

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Mammals of unusual size

When we've gone to the Museum of Natural History in Washington, D.C., I always gravitate toward the prehistoric animals.

I guess that's understandable enough, given that I made my career as a biology teacher.  Judging by the crowds, I'm not alone.  However, unlike most folks -- who seem especially taken by dinosaurs like T. rex and triceratops -- I always head toward the prehistoric mammals.

I love to picture what "endless forms most beautiful and most wonderful" (to pilfer a phrase from Darwin's Origin of Species) crawled, ran, jumped, scampered, and thundered across the planet long before we ever showed up on the scene.  Mammals have been around for a long time, a lot longer than you might think if you learned that "mammals arose once the dinosaurs were extinct" in grade school.  The first certain mammal fossils date from the late Triassic, about 225 million years ago, so at that point the non-avian dinosaurs still had around 160 million years to enjoy their hegemony before the double-whammy of the Chicxulub Meteorite Impact and the eruption of the Deccan Traps in India wiped them out.

The mammals were small for a while, of course.  Prior to the Cretaceous extinction, most of them fell into one of three groups; multituberculates (which looked superficially like rodents, but were only distantly related), eutriconodonts (a bit weasel-like, but again, not related), and spalacotheriids (something like a modern mole, but once again...).  None left any living descendants, and the biggest ones were the size of a small dog.

Understandable that they did what they could not to be noticed when there were loads of hungry dinosaurs around.

It's true that once the non-avian dinosaurs were wiped out, there was significant evolutionary pressure to diversify and get larger, to take advantage of the niches emptied by the mass extinction.  And one of the groups that got big fast were the brontotheres -- Greek for "thunder beasts."

They, like other mammal groups, started small.  They're perissodactyls -- the "odd-toed ungulates," a group that contains modern horses, rhinos, and tapirs.  And although they looked superficially like rhinos, their teeth show a closer relationship to horses.  One of the classic brontotheres is the slingshot-horned Megacerops (formerly named Brontops):

[Image licensed under the Creative Commons Creator:Dmitry Bogdanov, Megacerops-coloradensis, CC BY 3.0]

The reason this comes up is a paper last week in Science, which I found about from my author friend (and frequent contributor to Skeptophilia) Andrew Butters, in which a team from the University of Alcalá in Madrid used patterns of evolution in brontotheres to investigate Cope's rule -- that in the absence of other factors, larger individuals have a higher survival rate, and species evolve to get larger over time.

The results certainly seem to hold here.  The survival rate of brontothere species during the Eocene Epoch, from 55 to 34 million years ago -- their heyday -- is directly proportional to their size.  However, one corollary to Cope's rule is that when conditions suddenly change, large species are less able to respond flexibly, and are more prone to extinction.  Which is exactly what happened at the end of the Eocene; by the beginning of the next epoch, the Oligocene, the brontotheres were gone.

It was hardly the end of the large mammals, however.  Another perissodactyl group, the rhinos and their relatives, stepped in to fill the empty niches, and this led to the largest terrestrial land mammal known, Paraceratherium (formerly called Baluchitherium and Indricotherium).

[Image licensed under the Creative Commons Dmitry Bogdanov creator QS:P170,Q39957193, Indricotherium11, CC BY 3.0]

Standing next to Paraceratherium, you'd have come up to his kneecap.

If that's not scary enough, the Oligocene also saw mammals like the enormous Daenodon -- the name means "terrible teeth" -- which looked a bit like a pig on stilts:

[Image licensed under the Creative Commons Max Bellomio, Daeodon shoshonensis , CC BY-SA 4.0]

Oh, and there were also phorusrhacids stomping around the place.  Colloquially known as "terror birds."  Think of an enormous carnivorous ostrich on steroids, and you have the idea.

So yeah.  Even though I love hanging around in the prehistoric mammal part of the Museum of Natural History, it would be another thing entirely to go back there and actually try to survive.  An Eocene Park or Oligocene Park would be just as terrifying as a Jurassic Park.

Nature is red in tooth and claw, and all that sort of stuff.  Guess it always has been.

In any case, it does make me glad that the scariest thing I have to deal with around here are squirrels, raccoons, and the occasional coyote.  I'll take those over "thunder beasts," "terrible teeth," and "terror birds" any day.

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Picky eaters

Last week a gardener friend and I were talking about the fact that some plants are extreme specialists -- they only thrive in a very narrow range of conditions.

The classic example of this are orchids.  Virtually all orchid species only do well if you can somehow replicate the exact conditions of temperature, soil pH, soil mineral content, sunlight, and so on that they need.  Some also require the presence of symbiotic fungi (such as mycorrhizae) that infiltrate the orchid's roots and aid in nutrient and water uptake.  All of this is why if you ever are lucky enough to see an orchid growing in the wild, resist the temptation of digging it up and bringing it home for your garden.  The chances are nearly one hundred percent that all you'll succeed in doing is killing it in short order.  (Also, if you live in a place with laws against harming endangered species, you might be looking at serious fines if you get caught.)

It's an interesting question to consider why such extreme specialization evolves.  On first glance, it seems like it'd be better for all species to evolve toward becoming generalists -- able to handle a wide range of conditions.  The thing is that while generalists (like dandelions and crabgrass) do thrive just about everywhere, giving them a competitive edge in disturbed habitats (like cities) where not much else grows, they get beaten by the specialists in old, stable ecosystems.  The specialists have evolved to tolerate those specific conditions better than anything else.

It's why in old-growth rain forests, just about everything you see -- plant and animal -- is a specialist.  Along roadside ditches, they're all generalists.

Some recent research suggests that this drive toward specialization in stable habitats is very old.  A study of the distribution of animals in Ediacaran (very late Precambrian) sandstone in Australia found that some of the peculiar animals characteristic of these ecosystems showed a distinct preference for particular parts of the habitat -- a clear hallmark of specialization.

The researchers focused on a handful of species that have no living descendants, including Obamus coronatus (which looks like a French cruller) and the hubcap-like Tribrachidium heraldicum, one of the only known animals to have triradial symmetry.

Artist's reconstruction of Obamus coronatus [Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com/), Obamus NT, CC BY-SA 4.0]

Both animals were grazers, feeding on the microbial mat on the seafloor, but their habitat choices differed.  Obamus turned out to have a distinct preference for places where the mat was thickest; Tribrachidium was much more evenly dispersed.  And since both animals were of very low mobility -- similar to modern barnacles -- this didn't just reflect the chance arrangement of where they were when the a layer of sediment, probably stirred up by a storm or landslide, buried them for eternity.

This was a habitat choice -- and the first known example of specialization in the natural world.

"We think about the very oldest animals and maybe you wouldn't expect them to be so picky," said Mary Droser of the University of California - Riverside, who co-authored the study. "But Obamus only occurs where there is a thick mat, and it's a pretty sophisticated way of making a living for something so very old...  There are a limited number of reproductive strategies, especially for animals like these.  There are more strategies today, and they're more elaborate now. But the same ones used today were still being used 550 million years ago."

"It's not like studying dinosaurs, which are related to birds that we can observe today," said Phillip C. Boan, also of UC - R, and lead author of the new study.  "With these animals, because they have no modern descendants, we're still working out basic questions about how they lived, such as how they reproduced and what they ate...  This is really the first example of a habitat-selective Ediacaran creature, the first example of a macroscopic animal doing this.  But how did they get where they wanted to go?  This is a question we don't yet know the answer to."

It's fascinating that we can get some insight into the behavior of a species that lived so long ago, during a time where there was no life at all on land.  Imagine it -- everything alive is in the sea, and the continents were vast, barren expanses of rock, sand, and dust.  The first land-dwelling plants and animals wouldn't exist for another fifty million years (and even then, they were clustered around bodies of water; the central parts of the continents would have been lifeless for a great deal longer).  

But despite how alien this landscape would have seemed, organisms were already evolving through natural selection to have many of the same traits we see today -- including the fact that some of them, like modern orchids, know exactly where they want to be.

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Species, types, and the "No True Scotsman" fallacy

One of the most frustrating of logical fallacies is the No True Scotsman fallacy.

It gets its name from an almost certainly apocryphal story, in which a serial rapist and killer is being pursued by the police in Glasgow, and a Scottish MP encourages the police to search amongst the immigrant population of the city.  "No Scotsman would do such a thing," the MP said.

When the criminal was caught, and turned out to be 100% Scottish, the MP was challenged about his remark.

"Well," he said, drawing himself up, "no true Scotsman would have done such a thing!"

The crux of this fallacy is that if you make a statement that turns out, in view of evidence, to be false, all you do is shift your ground -- redefine the terms so as to make your original point unassailable.

Very few other fallacies have such a capacity for making me want to smack my forehead into a wall as this one.  Someone who commits this fallacy can't be pinned down, can't be backed into a corner, can't receive his comeuppance from the most reasoned argument, the most solidly incontrovertible evidence.  The dancing skills of a master of the No True Scotsman fallacy are Dancing With The Stars quality.

All of this comes up because of an online discussion that I read, and (yes) participated in, a couple of days ago, on the topic of the demonstrability of evolution.  Someone, ostensibly a supporter of evolution but seemingly not terribly well-read on the subject, was using such evidence as the fossil record as a support for the idea.  A creationist responded, "The fossil record, and fossil dating, are inaccurate.  You evolutionists always think that bringing us a bunch of bones and shells proves your point, but it doesn't, because no one can really prove how old they were, and none of them show one species turning into another.  You can't show a single example, from the present, of one species becoming another, and yet you want us to believe in your discredited theory."

Of course, I couldn't let a comment like that just sit there, so I responded, "Well, actually, yes, I can.  I know about a dozen examples of speciation (one species becoming another) occurring within a human lifetime."

Challenged to produce examples, I gave a few, including the ones that I described in an earlier post (Grass, gulls, mosquitoes, and mice, February 9, 2012), and then sat back on my haunches with a satisfied snort, thinking, "Ha.  That sure showed him."

Well.  I should have known better.  His response, which I quote verbatim: "All you did was show that one grass can become another grass, or a mosquito can become another mosquito.  If you could show me a mosquito that turned into a bird, or something, I might believe you."

Now, hang on a moment, here.  You asked me for one thing -- to show one species turning into a different species, in the period of a few decades.  I did so, adhering to the canonical definition of the word species.  And now you're saying that wasn't what you wanted after all -- you want me to show one phylum turning into a different one, in one generation?

I sat there, sputtering and swearing, and not sure how to answer.  So I said something to the effect that he'd pulled a No True Scotsman on me, and had changed the terms of the question once he saw I could answer it, and he'd damned well better play fair.  He humphed back at me that we evolutionists couldn't really support our points, and we both left the discussion as I suspect most people leave discussions on the internet -- unconvinced and frustrated.  So I was pondering the whole thing, and after taking my blood pressure medications I had a sudden realization of where the confusion was coming from.  It was from the idea of a type of organism.

Most people who aren't educated in the biological sciences (and I'm not including just formal education, here; there are many people who have never taken a single biology class and know plenty about the subject) really don't understand the concept of species.  They think in types.  A bird is one type of thing; a bug is a different one.  If you pressed them, they might admit that there were a few types of birds that seemed inherently different.  You have your big birds (ostriches), your medium-sized birds (robins), and your little birds (hummingbirds).  I've had students that have thought this way, and when they hear I'm a birdwatcher, they seem incredulous that this could be a lifelong avocation.  Wouldn't I run out of new birds to see pretty quickly?  When I tell them that there are over 10,000 unique species of birds, they seem not so much awed as uncomprehending.

The phylogenetic tree of birds (Class Aves) [credit: Dr. Gavin Thomas, University of Sheffield, UK]

I suspect that the source of this misapprehension is the same as the source of the general misapprehension regarding the antiquity of the Earth and the origins of life: the Bible.  In Leviticus 11, where they go through the whole unclean-foods thing that eventually would be codified as the Kosher Law, they split up the natural world in only the broadest-brush terms; you have your animals that have hooves and chew the cud, various combinations of ones that don't, creatures that have fins and scales and ones that don't, insects that jump and ones that don't, and a few different classes of birds (which, to my eternal amusement, includes bats).  And that's pretty much it.  Plants were sorted out into ones that had edible parts (wheat, figs, olives), ones that had useful wood (boxwood, cedar, acacia), and ones that had neither of the above (thorn bushes).  And these distinctions worked perfectly well for a Bronze-Age society.  It kept you from eating stuff that was bad for you, told you what you could build stuff from, and so on.  But as a scientific concept, the idea of "types of living things" kind of sucks.  And yet it still seems to live on in people's minds, lo unto this very day.

So, anyway, that was my brief excursion into that least useful of endeavors, the Online Argument.  It gave me a nice example of the No True Scotsman fallacy to write about here.  And it really didn't affect my blood pressure all that much, but it did make me roll my eyes.  Which seems to happen frequently when I get into conversations with creationists.

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The worst century in history

I've always loved a mystery, and for that reason, the European "Dark Ages" have fascinated me for as long as I can recall.

But the moniker itself is off-puttingly self-congratulatory, isn't it?  It's not like Roman rule was that pleasant for your average slob to live under, after all.  Be that as it may, after the conquests of the Roman Empire started to fall apart in the fourth century C.E. from a combination of invasion, misrule, and downright lunacy, things went seriously downhill.  Life was pretty rough until the eighth and ninth centuries, when some measure of order returned as damn near all of Europe coalesced around the Roman Catholic Church, ushering in the Middle Ages.  And what we know about the period in between is... not a hell of a lot.  Accounts are scattered, vague, and full of conflation with mythology and legend.  The few that were written by contemporaries, rather than long after the fact -- such as Gregory of Tours's History of the Franks -- contain as much hagiography as they do history.

St. Gregory and King Chilperic I, from Grandes Chroniques de France de Charles V (fourteenth century) [Image is in the Public Domain]

Which is why I was thrilled to read a paper that appeared in Antiquity about a study of the "worst decade to be alive" -- 536-546 C. E.

The research, which combines the skimpy evidence we have from accounts written at the time with hard scientific data from analysis of ice cores, paints a grim picture.  Writings from the year 536 describe a mysterious "fog" that lasted for eighteen months, generating widespread crop failure and what one Irish cleric called "three years without bread."  From the ice core analysis, medieval historian Michael McCormick and glaciologist Paul Mayewski identified what they believe to be the culprit: a cataclysmic volcanic eruption in Iceland that dropped the global temperature an average of two degrees Celsius in a matter of months.

This was followed by another eruption in 540, and the following year, the single worst plague on record -- the so-called "Plague of Justinian," which killed between a third and a half of the inhabitants of the Eastern Roman Empire, and resulted in so many corpses that people loaded them on ships and dumped them in the Mediterranean.  The disease responsible isn't known for certain, but is believed to be Yersinia pestis -- the same bacterium that caused the Black Death, almost exactly eight hundred years later.  But to give you an idea of the scale, there's reason to believe the Plague of Justinian dwarfed both the fourteenth century Black Death and the Spanish Flu of 1918-1919 -- usually the two examples that come to mind when people think of devastating pandemics.  The death toll is estimated at sixty million.

There probably was a connection between the cold and the plague, too, although not the obvious one that famine triggers disease susceptibility.  Many scholars think that the lack of food, and cold temperatures following a period that had generally been warm, forced mice and rats into homes and on board ships -- not only in close proximity to humans, but in their means of travel.  The fleas they carried, which are vectors for the plague, went with them, and the disease decimated Europe and beyond.

The effects of the eruption, however, were felt all over the Earth.  Tree ring analysis from North America shows 540 and the years following to have been unusually cold, with short-to-nonexistent growing seasons.  Volcanic dust is found in those layers of ice cores everywhere they exist.  Famines occurred in Asia and Central America.

All in all, a crappy time to be around.

Things didn't rebound for almost a hundred years.  Archaeologist Christopher Loveluck, of the University of Nottingham, found traces of dust containing significant amounts of lead in ice strata from the year 640, which he believes were due to a resurgence in silver smelting for coinage.  (I suppose if there's a hundred years during which your three main occupations are (1) not starving, (2) not freezing, and (3) not dying of a horrible disease, then making silver coins is kind of not on your radar.)  And the tree rings and ice cores bear out his contention that this indicates better conditions; although there were a couple of other volcanic eruptions we can see in the glacial records, none were as big as the one in 536.  The silver smelting, Loveluck says, "... shows the rise of the merchant class for the first time."  Things, finally, were improving.

What's coolest about this study -- despite its gruesome subject -- is how hard science is being brought to bear on understanding of history.  We no longer have to throw our hands up in despair if we're interested in a time period from which there were few written records.  The Earth has recorded its own history in the trees and the glaciers, there for us to read -- in this case, telling us the tale of the worst century the human race has ever lived through.

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Fish star

Fomalhaut is the brightest star in the southern constellation of Piscis Austrinus, the Southern Fish.  At a declination (stellar latitude) of −29° 37′, it's seldom visible where I live, but I did get a good look at it when I was in Ecuador a few years ago.  It's bright -- a first-magnitude star -- but looked brighter because of the elevation; when you're up in the mountains, on a clear night it's hard to recognize constellations because there are so many visible stars.

The star's odd moniker comes directly from the Arabic Fom al-Haut, "the mouth of the whale."  As always, though, other cultures saw it differently.  The Chinese gave it the fanciful name Běiluòshīmén, meaning "the north gate of the military camp."  To the Persians it was Hastorang, one of the "Four Royal Stars."  (The other three were Aldebaran, Regulus, and Antares.)  It seems to have had some significance to indigenous Americans; the two-thousand-year-old Earthwork B, in Mounds State Park in Indiana, seems to line up with the rising of Fomalhaut, but the reason is unknown.  To the Moporr, an indigenous people in South Australia, it was a powerful male deity named Buunjill.  Not to be outdone, in the Lovecraftian mythos Fomalhaut is the home of the Great Old One Cthugha, who appeareth unto mankind as a fiery sphere and basically scareth the absolute shit out of everyone who seeeth him.

More prosaically, though, Fomalhaut is interesting to astronomers as the eighteenth brightest star in the sky overall, and the third brightest star known (or thought) to have a planetary system (after the Sun and Pollux).  It's young, something on the order of four hundred million years old.  (I know that seems pretty damn old, but keep in mind that the Sun is over ten times older than that.)  It's a Type A star, which doesn't mean that it's hard-working and tightly-wound, but that it's blue-white in color and has strong emission lines from hydrogen and ionized metals.  (Another, better known, Type A star is Vega, made famous as the home system of the aliens in the wonderful movie Contact.)

What's coolest about this star, though -- and the reason it comes up today -- is its ring of dust and debris, which was photographed directly in 2012 by ALMA (the Atacama Large Millimeter/submillimeter Array):

[Image licensed under the Creative Commons LMA (ESO/NAOJ/NRAO). Visible light image: the NASA/ESA Hubble Space Telescope ; Acknowledgement: A.C. Boley et al., ALMA observes a ring around the bright star Fomalhaut, CC BY 4.0]

The James Webb Space Telescope just got even more detail; it was able to discern not only the outer ring of debris but an inner ring, comparable to the Sun's Kuiper Belt and Asteroid Belt, respectively. which suggests to astrophysicists that there are planets gravitationally "herding" the debris into rings, just as Neptune and Jupiter do for our two belts.

"I would describe Fomalhaut as the archetype of debris disks found elsewhere in our galaxy, because it has components similar to those we have in our own planetary system," said András Gáspár of the University of Arizona in Tucson, lead author of the paper, which appeared in Nature Astronomy last week.  "By looking at the patterns in these rings, we can actually start to make a little sketch of what a planetary system ought to look like -- if we could actually take a deep enough picture to see the suspected planets."

"Where Webb really excels is that we're able to physically resolve the thermal glow from dust in those inner regions," said Schuyler Wolff, also of the University of Arizona in Tucson, who co-authored the paper.  "So you can see inner belts that we could never see before.  We definitely didn't expect the more complex structure with the second intermediate belt and then the broader asteroid belt.  That structure is very exciting because any time an astronomer sees a gap and rings in a disk, they say, 'There could be an embedded planet shaping the rings!'"

Or, you know, a Lovecraftian Elder God creating a fire vortex in the eldritch nether regions of the void.  You know how it goes.

In any case, it's incredibly cool to see what's coming in from the JWST.  Here, we're seeing a system that might be a little like what the Solar System looked like four billion years ago, as the planets were coalescing from the rocky debris of the protoplanetary disk.  The astronomers, of course, are going to give it a much closer look.  "The belts around Fomalhaut are kind of a mystery novel: Where are the planets?" said George Rieke, of the JWST's Mid-Infrared Instrument (MIRI) team, who also co-authored.  "I think it's not a very big leap to say there's probably a really interesting planetary system around this star."

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Mystery disk

I'm always fascinated by a good mystery, and that's definitely the appropriate category for an artifact called the Phaistos Disk.

Found in the Minoan palace of Phaistos, on the island of Crete, in 1908, the Phaistos Disk is fifteen centimeters in diameter, made of fired ceramic clay, and (most interestingly) has an inscription on it.  Here's a photograph:

[Image licensed under the Creative Commons C messier, Δίσκος της Φαιστού πλευρά Α 6380, CC BY-SA 4.0]

The Disk is thought to have been made in the second millennium B.C.E., making it approximately contemporaneous with the Linear B script of Crete, which was successfully deciphered in the early 1950s by Alice Kober, Michael Ventris, and John Chadwick.  This accomplishment was the first time that anyone had cracked a script where not only was the sound/letter correspondence unknown, but it wasn't even known what language the script was representing.  (As it turned out, it was an early form of Mycenaean Greek.  Earlier guesses were that it represented Etruscan, a proto-Celtic language, or even Egyptian.  The script itself was mostly syllabic, with one symbol representing a syllable rather than a single sound, and a few ideograms thrown in just to make it more difficult.)

The problem is, the Phaistos Disk is not Linear B.  Nor is it Linear A, an earlier script which remains undeciphered despite linguists' best attempts at decoding it.  The difficulty here is that the Phaistos Disk has only 242 different symbols, which is not enough to facilitate translation.  Some seem to be ideographic, but as you undoubtedly know, many symbols that start out as pictographic end up representing phonetic units, so we can't rely on "it looks like a dog so it means 'dog'."  Once again, we're not sure what the language is, although it's a good guess that it's some form of Greek (other linguists have suggested it might be Hittite or Luwian, both languages spoken in ancient Anatolia (now Turkey), and which had their own alphabet that bears some superficial similarities to the symbols on the Disk).

This lack of information has led to wild speculation.  Various people have claimed it's a prayer, a calendar, a story, a board game, and a geometric theorem, although how the hell you'd know any of that when you can't even begin to read the inscription is beyond me.  But it only gets weirder from there.  Friedhelm Will and Axel Hausmann back in 2002 said that the Disk "comes from the ruins of Atlantis."  Others have suggested it's of extraterrestrial origin.  (Admit it, you knew the aliens were going to show up here somehow.)

Others, more prosaically, think it's a fake.  In 2008 archaeologist Jerome Eisenberg proclaimed the Disk a modern hoax, most likely perpetrated by Luigi Pernier, the Italian archaeologist who claimed to have discovered it.  Eisenberg cites a number of pieces of evidence -- differences in the firing and in how the edges were cut, as compared to other ceramic artifacts from the same period; the fact that it's incredibly well-preserved considering how old it supposedly is; and vague similarities to Linear A and Linear B characters, with various odd ones thrown in (Eisenberg says the symbols were chosen to be "credible but untranslatable" and selected "cleverly... to purposely confuse the scholarly world."

Of course, this didn't settle the controversy.  Archaeologist Pavol Hnila cites four different artifacts, all discovered after the Disk, that have similar characters to the ones on the Disk, and that there is not enough evidence to warrant accusing Pernier and his team of something as serious as a deliberate hoax.

So the mystery endures, as mysteries are wont to do.  I find this fascinating but more than a little frustrating -- to know that there is an answer, but to accept that we may never find out what it is.  That's the way it goes, though.  If you're a true skeptic, you have to be willing to remain in ignorance, indefinitely if need be, if there is insufficient evidence to decide one way or the other.  This leaves the Phaistos Disk in the category of "Wouldn't this be fun to figure out?" -- a designation that is as common in science as it is exasperating.

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