A lens into the past

The third of C. S. Lewis's Space Trilogy, That Hideous Strength, is not without its serious flaws (itself an interesting topic and perhaps something I'll look at another time), but is a riveting adventure story even so, with twists, turns, near misses, and a finale where (literally) the world of the story comes crashing down on the characters.

Central to the tale is the famous character of Merlin, the master magician from the Arthurian legends, who has been in a charmèd sleep after his dalliance with the sorceress Nimué (also known as Ninienne or Vivienne, depending on which version you read).  Lewis's story, set in immediately post-World-War-II Britain, involves two different groups, one good and one deeply evil, who are both trying to reawaken Merlin and harness his powers for their own purposes.  They both have figured out that the sorcerer's not-so-final resting place is a souterrain, or underground chamber, beside a well on the grounds of the (fictitious) Bracton College, and each is racing to get there first.

Lewis's placement of the venerable Merlin in a souterrain is justified; Iron Age Celtic settlements were riddled with them.  Their purpose is unknown.  They may have been used for storage, for ritual purposes, as a hiding place when they were attacked (all too common in that violent time), all three, or perhaps something else entirely.  Excavating souterrains is understandably fascinating to archaeologists, who hope to learn something of the history of the ancient Britons, who left virtually no written records (and very few surviving artifacts of any kind).

It's also backbreaking and dangerous work.  In the intervening centuries, cave-ins and erosion from groundwater have choked most souterrains with debris that has to be cautiously excavated and removed (hopefully not triggering further ceiling collapse in the process).  So people interested in the history of the Celts -- and other cultures who tunneled under their settlements -- will be excited to find out that a team from London-based AOC Archaeology has figured out a way to see into some Scottish souterrains -- without anyone going inside.

Using a Leica BLK360 laser scanner, they were able to create a 3-D computerized image of Cracknie souterrain, in Borgie Forest (north-central Scotland), a curving tunnel which is thirteen meters long and was built around two thousand years ago.

"Souterrains are still an enigma," said Matt Ritchie, resident archaeologist at Forestry and Land Scotland, who contributed to the project.  "Perhaps they were for storage, such as grain in sealed pots or dairy products like cheese.  Perhaps they were for security, keeping valuables safe, or slaves or hostages secure.  Or perhaps they were for ceremonial purposes, for household rituals, like a medieval shrine or private chapel...  [Cracknie souterrain] is one of the most important scheduled monuments on Scotland's national forests and land...  To do the equivalent of what we did with a theodolite [a precision optical instrument often used to map out caves], you would be there a long time."

Here's the map the laser scanner created:

This is only the beginning, of course; once you have proof-of-concept, the technology is bound to improve.  Soon, it will likely be possible to get a detailed image of the interior of a rubble-choked cavern where humans haven't set foot for millennia -- without moving a single pebble.

I, for one, can't wait to see what they find.  I'm one-quarter of Scottish descent, and have always felt a particular fascination for the history, language, music, and culture of the Celts.  It would be amazing to have a laser-powered lens into their past -- and a better idea of how my distant ancestors lived thousands of years ago.

And if they do end up finding Merlin, I'm all for waking him up.  This world could use a good dose of Elder Magic.

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Tooth and claw

Aficionados of The X Files will no doubt recall "Field Trip," which ranks amongst the creepiest, twistiest, most atmospheric episodes they ever did.  Fox Mulder and Dana Scully are charged with investigating the disappearance of a young couple while on a hiking trip -- and after that, their mantra "Trust nothing and no one" becomes literally true.

What had happened (obviously, *spoiler alert*) is that first the couple, and then Mulder and Scully, had been attacked by an underground fungus that works in a particularly insidious way.  Inhaling the spores, which are released whenever you take a step on the ground, induces hallucinations intended to make you hold still while the fungus slowly digests you.  It stimulates your brain with images while dissolving away your body.  Every time the real reality -- the tendrils of slime mold creeping across your skin -- intrudes, the hallucinations become more intense, more engaging, more real.

Until there's nothing left of you to fight back.

While the details of the episode are fiction, nature itself has plenty of examples that are just as horrifying.  The pathogen Toxoplasma gondii, common not only in humans but in domestic cats, wild mice, and rats, alters the brains of the hosts, but each in its own way.  Rats and mice become unafraid of predators, and in fact become attracted to the scent of cat urine; cats and humans become more affectionate -- and neurotic.  Each of those alterations in behavior is engineered by the parasite to maximize its chances of jumping to another host.  Lancet worms (Dicrocoelium dendriticum) parasitize ground-dwelling ants, and induce them to climb blades of grass and simply wait there, because the worm has a second stage of its life cycle in which it has to pass through the digestive tract of a ruminant, like a deer or a cow.  So it basically triggers the ant to commit suicide so it can make the jump.  Worse of all -- and most like the fungus in "Field Trip" -- there are the baculoviruses, which infect caterpillars.  Once parasitized, the caterpillars become attracted to sunlight, so they climb to the very tops of tree branches, where they die.  And then explode, showering their comrades lower down in the tree with viral particles.

Another way that "Field Trip" got it right, though, was some of the nasty stuff pulled by members of kingdom Fungi.  You have to wonder how we ever figured out that any of them were edible:

Not only are some of them amongst the most toxic living things known (the closely-related death cap [Amanita phalloides] and destroying angel [Amanita bisporigera] mushrooms, for example), they have a lot of other insidious strategies.  Most fungi are decomposers, but like the fungus in "Field Trip," a few of them have developed methods for hastening their unfortunate prey into decomposition.

This, in fact, is why the topic comes up; a new study of oyster mushrooms (Pleurotus ostreatus) found that the underground mycelium (network of root-like tubes) of the species actually hunts and kills nematodes (roundworms) using something one of researchers described as "a lollipop filled with nerve gas."  The toxocysts, as the lollipops are called, are consumed by the nematodes, and when they burst, it releases a chemical called 3-octanone, which triggers calcium to flow into the muscles of the worm.  This paralyzes it -- and the fungus has dinner.

Oyster mushrooms aren't the only species that goes after nematodes.  It makes sense to choose them as prey; nematodes are one of most numerous animals in the world.  I still recall my invertebrate zoology professor grossing us all out (something he specialized in) by telling us that if you made all organic matter disappear except for nematodes, you could still see where all the other life forms were by the haze of parasitic nematodes they'd been carrying, outlining where they'd been like some kind of ghostly remnant of their bodies.

But the fungi still maintain the upper hand.  There are fungi which have evolved harpoons for skewering nematodes.  Others create what amount to glue traps.  One species produces something like a spiked collar -- with the spikes pointing inward.  The weirdest one is the fungus Arthrobotrys oligospora, which creates a noose.  When a nematode crawls through the noose, the loop suddenly inflates, strangling the hapless worm, which is then digested.

Nature is red in tooth and claw, man.  And it's not just the animals.  Remember the first line of Stephen King's wonderful novel The Girl Who Loved Tom Gordon: "The world had teeth, and could bite you with them any time it wanted."

Truer words never spoken.

Anyhow, I've probably skeeved you out sufficiently for one day.  Just think about all this next time you see innocent-looking little mushrooms popping up in your lawn. 

You never know what's going on beneath the surface.

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Jerusalem, in England's green and pleasant land

A loyal reader of Skeptophilia asked me, rather offhand, if I'd heard of "British Israelism."  I hadn't, and he went on to explain that it's the idea that the British (and therefore Americans of British ancestry) are the descendants of the Ten Lost Tribes of Israel.

As soon as I heard that last bit, I said, "Uh-oh."  I did a piece a while back about the fact that there are so many groups claiming to be the descendants of the Ten Lost Tribes that calling them "lost" is something of a misnomer.  In fact, if you do any reading on the topic, you'll come away with the impression that you can't throw a rock without hitting a Ten Lost Tribesman.

Delegation of the Northern Kingdom of Israel bringing gifts to Assyrian King Shalmaneser III [Image licensed under the Creative Commons Osama Shukir Muhammed Amin FRCP(Glasg), Black Obelisk side 4 Jewish delegation, CC BY-SA 4.0]

But even so, the British Israelists are in a class by themselves, given how thoroughly fleshed-out their ideas are.  I mean, the ideas are horseshit, but it's amazingly detailed horseshit.  Here are a few of their chief tenets:

• The Ten Lost Tribes were not Jews.  More on that in a moment.
• The Scythians were the ancestors of the Scottish people.  Because, y'know, both start with "Sc" and all.
• The Saxons were connected to Isaac, son of Abraham.  "Saxon" comes from "[I]saac's sons."
• All of the place names that have a syllable of the form "/d/-vowel-/n/" come from the Tribe of Dan.  So London, Dunkirk, Dundee, and... I shit you not... Danube, Denmark, and Macedonia.  Also, this has something to do with the Tuatha Dé Danann, "the children of Danu," who were a supernatural race revered in pre-Christian Ireland.
• The royal family of Britain descends from King David of Israel.  Because reasons, apparently.
• The English are from the Tribe of Ephraim, and Americans are from the Tribe of Manasseh.  Don't ask me how this works, because even after reading about it fairly extensively, I have no idea.

Well, the first thing that comes to mind about all of this is that the Israelists have broken a cardinal rule, to wit, "don't fuck with a linguist."  None of their supposed etymologies are even within hailing distance of the truth.  Just looking at the "Tribe of Dan" ones -- of which none have anything to do with the Tribe of Dan -- let's start with Dundee and Dunkirk, which both contain the Celtic word dun meaning "fort" (as do Dunblane, Duncannon, Dunearn, Dunfermline, and dozens of others).  London comes from the Latin Londinium (which was probably a latinization of a Celtic place name).  Danube comes from the Celtic Danu (the same gods referenced in the Tuatha Dé Danann, but the fact that they were right about that one thing brings to mind my dad's remark that "even a stopped clock is right twice a day").  Denmark comes from a Germanic tribe called the Dani.  Finally, Macedonia comes from the ancient Greek μακεδνόι, which means "tall people."

Put a different way, linguistics is not some kind of bastard child of free association and the Game of Telephone.

The bottom line is, it's mighty odd if the English are direct descendants of the Israelites, there is not a shred of evidence -- anthropological, genetic, linguistic, or archeological -- of that connection.  What the Israelists have is an amalgam of quasi-evidence (mostly in the form of folk legends and mythology), mixed well with misinterpretations and outright falsehoods.  Despite all that -- to my astonishment -- it still has its fervent adherents, including the leaders of the Church of God International and the members of the Christian Identity movement.

Where it gets uglier, though, is that the Israelists, especially after the idea took hold in the United States, devolved into sickening levels of antisemitism.  This initially puzzled me, because you'd think that any group so gung-ho about the Israelites would be equally chummy with the Jews, but no.  The leading proponents of the idea have taken great pains to distance themselves from modern-day Jews, whom they consider "usurpers" and "imposters."  Some go so far as to believe that modern Jews aren't the descendants of the Israelites at all, but come either from Adam having sex with the demonic Lilith, or the Serpent having sex with Eve, or possibly both.  Anthropologist Michael Phillips, commenting on this bizarre doctrine, said that the belief allowed an adherent to "maintain his anti-Semitism and at the same time revere a Bible cleansed of its Jewish taint."

All of which illustrates something we've seen here before, which is that bigoted assholes will latch on to any gossamer scrap of evidence they can find to support their abhorrent ideas, and failing that, will make some up.

Anyhow, to the reader who sent me the link, thanks for sending me down a several-hours-long rabbit hole that left me thinking if the Daleks ever invade the Earth, I might just tell 'em, "Exterminate away, little buddies, there's no intelligent life down here anyhow."  Every time I think I've plumbed the absolute depth of stupidity, I find that someone has found the bottom and started to dig.

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Scripts and mysteries

My fascination with languages goes back a very long way.  I was raised bilingual -- French was my mother's first language, and all of her older relatives spoke French more often than English.  They especially tended to switch over to French when they were talking about things they didn't want me to understand, which I have to admit provides a kid a hell of an incentive to learn a language.

Another thing I loved when I was young (and still do) is puzzles.  I have always resonated with what physicist Richard Feynman called "the joy of figuring things out."  That flash of insight that allows you to solve a riddle is a nice little dopamine rush.

The combo is probably why I pursued a master's degree in historical linguistics.  Piecing together the etymologies of words, and tracing how they change and move from place to place, is like a gigantic linguistic puzzle.  My own particular area was how the Scandinavian languages influenced Old English and Old Gaelic during the Viking invasions of Great Britain, but etymology is just generally fascinating to me (which is why I started doing my daily #AskLinguisticsGuy feature on TikTok -- if you're interested in word origins, you should follow me).

One area that is way outside my skill set, though, is decipherment.  I've written here before about the stupendous work of Alice Kober and Michael Ventris in deciphering the Linear B Script of Crete, for which not only was the sound-to-symbol correspondence unknown, but it wasn't known what language it represented.  At first, they couldn't even be certain if it was read left-to-right or right-to-left, or if -- perhaps -- it was a boustrophedonic script, which alternates being read left-to-right and right-to-left every line.  (The odd word boustrophedonic comes from Greek; it means "the turning of an ox," because the back-and-forth writing reminded linguists of the way an ox plows a field, turning at the end of each row.  Examples of boustrophedonic scripts are Etruscan and Sabaean.)

If you're curious, Linear B turned out to be written in an early form of Mycenaean Greek, and the script was a combination of a syllabic script -- like the Japanese hiragana -- and ideographs, such as are used in written Chinese.  It's read left-to-right -- just as modern Greek is today.

The amount of skill and sheer brainpower it would take to figure all that out that absolutely boggles my mind.

If any of you are looking for a challenge, though, there are still a lot of undeciphered scripts out there.  Here are a few examples of writing systems that have defied decipherment -- thus far:

• The Banpo symbols, from the fifth millennium B.C.E. in China.  They consist of twenty-two different symbols, and are always found on shards of pottery, leading some to speculate that they aren't writing, but are either just geometrical decorations or (possibly) what potters call a "chop," a mark or series of marks identifying the maker.  The fact that they're present on multiple pieces of pottery, in different orders, suggests that they might be written language, but no one knows for sure.

• The Dispilio Tablet, a wooden artifact with what seem to be written characters.  It was found in 1993 in western Greece, and the shapes of the characters drew comparisons to both Linear B and Linear A (another Cretan script that is, thus far, undeciphered).  But the comparisons didn't allow linguists to crack the code, and as of right now, the Dispilio script, like Linear A, is still a mystery.

• The Indus Valley script.  This is one of the most puzzling undeciphered scripts known, because it has been recorded from over four thousand inscriptions comprising strings of around four hundred different symbols, and has defied all attempts at decipherment.  Part of the problem is that we don't know what language was spoken by the people of the Harappan Civilization, which produced the writing and flourished in the Indus River Valley for two millennia, between 3300 B.C.E. and 1300 B.C.E.  At the end of that long period of dominance, their cities and farming communities were suddenly abandoned, and although climate change, disease, and invasion have been suggested as explanations, historians are at a loss to explain what actually happened.

A sequence in the Indus Valley script [Image licensed under the Creative Commons Siyajkak derivative work: Gregors (talk) 08:30, 31 March 2011 (UTC), The 'Ten Indus Scripts' discovered near the northen gateway of the citadel Dholavira, CC BY-SA 3.0]

• Proto-Elamite, a script used from around 3200 to 2700 B.C.E. in what is now western Iran.  Later, the Elamites adopted cuneiform, but their earlier writing system is still undeciphered.

• Southwestern Paleohispanic, a script used in southern Spain and Portugal from the eighth to sixth centuries B.C.E.  It's been associated with the Tartessian civilization, about which I've written here before, and which -- like the Harappans -- disappeared suddenly and inexplicably.  All attempts to link Southwestern Paleohispanic to Celtic, Etruscan, Latin, and Greek have been unsuccessful.

• Zapotec, a glyphic script (like Mayan) used in what is now Oaxaca, Mexico up until about 700 C.E.  It is probably a written representation of an early ancestor of the Oto-Manguean language family, a cluster of about fifty languages from Mesoamerica whose relationship to other language families is uncertain at best.

That's just six of the best-known.  There are literally hundreds of other scripts, some fragmentary in nature or only known from one or two artifacts, that have thus far resisted all attempts at decipherment.

And if the whole business wasn't already complicated enough, there are also examples of asemic writing, which is writing without meaning -- writing either created to simulate meaningful scripts for use as decoration (such as the delightful Codex Seraphinianus) or done deliberately to fool people (which is likely to be the explanation for the Voynich Manuscript).  So linguists studying some of these undeciphered scripts have to keep in mind that the reason they've defied decryption might be because they aren't meaningful in the first place.

But, as I said, figuring that out is above my pay grade, not to mention my IQ.  I can only sit back in amazement and appreciate the work that has gone into figuring out all the thousands of ways humans have communicated, by linguists whose ability to tackle unfathomable puzzles is nothing short of astonishing.

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A twist in the fabric

All of us learned about gravity in elementary school, often starting with the anecdote about Isaac Newton seeing a falling apple and wondering why it was pulled toward the Earth.  What's weirdest about the phenomenon, though, is that while we can characterize gravitational force mathematically to just about any precision you want, explaining why it works is not nearly so easy.  Einstein, in his General Theory of Relativity, visualized it as a warping of space -- that anything with mass literally pulls on the spacetime fabric, in much the way that a heavy weight depresses the surface of a trampoline.  Picture rolling a small ball toward the weight on the trampoline; the ball will speed up, but it's not because the weight is somehow magically pulling on the ball.  It's because the ball is following the contours of a warped space.

Move that two-dimensional model up by one dimension, and you have an idea of how gravity operates.

Even Einstein, though, couldn't figure out how to make his gravitational model work in the realm of the very small.  Trying to unite the theory of gravity with the theories of quantum mechanics has, so far, proven impossible.  That combo -- called a "Grand Unified Theory" -- has defied the best minds in the field.  In fact, just last month an experiment in Italy failed to find predicted violations of Pauli's Exclusion Principle which would have supported some of the leading contenders for a unified model, most notably string theory.

So it's back to the drawing board.  And despite astrophysicist Neil deGrasse Tyson's statement that "scientists are always at the drawing board," this has got to be frustrating -- and raises question of whether a unified theory of gravity and quantum physics is even possible.

Meanwhile, a bit like the apocryphal bumblebee who by the principles of aerodynamics can't fly but doesn't know this so goes ahead and flies anyhow, gravity continues to warp space all around us even though we can't really explain it.  Just as well, because otherwise we'd obey Newton's First Law of Motion and go flying off the Earth at our current rate of speed in a direction tangent to its surface, until we encountered a fixed object, which in my case would be the wall of my house.

And out in space, gravity keeps twisting the fabric of spacetime, resulting in some pretty amazing structures.  In fact, this is why the topic comes up; just last week, there were two studies looking at the effects of extreme gravity on astronomical objects, both of which will make you glad we live here on a paltry little planet with a relatively small ability to warp space.

The first, out of the University of Washington, looked at the anomalous -- if beautiful -- shape of the Butterfly Nebula, the remnants of a star that exhausted its fuel and jettisoned the entire out of surface into a pair of mirror-image cones.

[Image is licensed under the Creative Commons Hubble ESA, NGC 6302 (50033189356), CC BY 2.0]

What apparently happened is that the star which blew up had a companion star, and the gravitational pull of that companion funneled the debris into the beautiful, gossamer "wings" the nebula shows today.  But even that hypothesis hasn't been enough to account for the nebula's odd shape.

"The Butterfly Nebula is extreme for the mass, speed and complexity of its ejections from its central star, whose temperature is more than two hundred times hotter than the Sun yet is just slightly larger than the Earth," said Bruce Balick, who led the team studying the nebula.  "I've been comparing Hubble images for years and I've never seen anything quite like it...  At this point, [all we have are] hypotheses.  What this shows us is that we don't fully understand the full range of shaping processes at work when planetary nebulae form.  The next step is to image the nebular center using the James Webb Space Telescope, since infrared light from the star can penetrate through the dust."

The second study, from NASA and the Goddard Space Flight Center, looked at a different way that a star can end its life.  It used data from the Hubble Space Telescope to look at a star in the galaxy ESO-583-G004, three hundred million light years away, and found evidence of a black hole that was in the process of swallowing a nearby star -- pulling it into a torus, or donut, shape.  It's unknown if the ill-fated star was already a companion to the black hole, or if it got gravitationally captured, but either way the outcome was the same.

I.e., not good.

The star was "tidally disrupted" -- for that, read "ripped to shreds" -- and the stellar material swung into an "accretion disk" as big as the Solar System.  "We saw this early enough that we could observe it at these very intense black hole accretion stages," said Peter Maksym, of the Harvard Center for Astrophysics, who co-authored the study.   "We saw the accretion rate drop as it turned to a trickle over time...  We're looking somewhere on the edge of that donut.  We're seeing a stellar wind from the black hole sweeping over the surface that's being projected towards us at speeds of twenty million miles per hour (three percent the speed of light).  We really are still getting our heads around the event.  You shred the star and then it's got this material that's making its way into the black hole.  And so you've got models where you think you know what is going on, and then you've got what you actually see.  This is an exciting place for scientists to be: right at the interface of the known and the unknown."

Right, in fact, at Tyson's "drawing board."

It's a thrilling time for scientists; so much is explained, but every question that's answered raises ten more questions.  The hydra-headed nature of science is just how it goes, though.  And even if some of the big questions do eventually get answered -- whether, for example, there's a quantum theory of gravity -- I don't think we'll be reaching the edges of what's knowable for a very long time.

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The memory virus

It's virus season, which thus far I've been able to avoid participating in, but every time I go to the grocery store I see people who are hacking and snorting and coughing and I figure it's only a matter of time, despite my insistence on wearing a mask in public.  Viruses are odd beasts; they're obligate intracellular parasites, doing their evil work by hijacking your cellular machinery and using it to make more viruses.  Furthermore, they lack virtually all of the structures that cells have, including cell membranes, cytoplasm, and organelles.  They really are more like self-replicating chemicals than they are like living things.

Simian Polyoma Virus 40  [Image licensed under the Creative Commons Phoebus87 at English Wikipedia, Symian virus, CC BY-SA 3.0]

What is even stranger about viruses is that while some of the more familiar ones -- colds, flu, COVID, measles -- invade the host, make him/her sick, and eventually (with luck) are cleared from the body -- some of them leave behind remnants that can make their presence known later.  This behavior is what makes the herpes family of viruses so insidious.  If you've been infected once, you are infected for life, and the latent viral genetic material hidden in your cells can cause another eruption of symptoms, sometimes decades later (as I found out the hard way when I got shingles a couple of years ago).

Even weirder is when those latent viral remnants cause havoc in a completely different way than the original infection did.  There's a piece of a virus left in the DNA of many of us called HERV-W (human endogenous retrovirus W) which, if activated, can trigger multiple sclerosis or schizophrenia.  Another one, Coxsackie virus, has an apparent connection to type-1 diabetes and Sjögren's syndrome.  Thus far, all of the viral infections, whether or not they're latent, are damaging to the host.  So it was quite a shock to me to read a piece of recent research that there's a viral remnant that not only is beneficial, but is critical for intercellular communication -- and individuals without it have trouble forming long-term memories!

In two separate papers published in the journal Cell -- "The Neuronal Gene Arc Encodes a Repurposed Retrotransposon Gag Protein that Mediates Intercellular RNA Transfer" and "Retrovirus-like Gag Protein Arc1 Binds RNA and Traffics Across Synaptic Boutons," each by a large team of neurobiologists and geneticists -- we learn about the proteins Arc and Gag, which were put into our cells by retroviruses (probably) hundreds of millions of years ago, and which generate virus-like particles that transfer from one brain cell to another.  This process seems to mediate memory formation, as mice that have the Arc/Gag gene knocked out are unable to retain long-term memories -- and may even be unable to form them in the first place.

As Sara Reardon explained it, writing in Nature:

Shepherd and Budnik [lead researchers in the two studies] think that the vesicles containing Arc play a part in helping neurons to form and break connections over time as an animal’s nervous system develops or adapts to a new environment or memory.  Although the fly and mouse versions of Arc are similar, they seem to have evolved from two distinct retroviruses that entered the species’ genomes at different times.  "There must be something really fundamental about it," Budnik says, for it to appear in both mice and flies... 

The human genome contains around 100 Gag-like genes that could encode proteins that form capsids.  It’s possible that this new form of communication between cells is more common than we thought, Shepherd says.  "We think it’s just the beginning."

Which is pretty astonishing.  The idea that some viruses might have beneficial effects on the host is weird enough; the idea that they could facilitate something as basic as memory storage is mind-blowing.  As such, they'd be a major driver for evolution -- given that organisms that have strong memory capacity are clearly at an advantage over ones that don't.

So before you curse the viruses this winter, be a little thankful for Arc and Gag and any other genetic parasites we might have that help us to function.  It may be small consolation if you are currently fighting a cold, but keep in mind that without viruses, you might not be keep anything in mind at all.

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Life inside the snowball

Right now, here in the wilds of upstate New York, it's cold, gray, and snowy.  They say our area has a "four-season climate" -- but usually neglect to add that the four seasons are Almost Winter, Winter, Still Fucking Winter, and Road Construction.

On the other hand, if you know something about prehistory, it could be a whole lot worse, and in fact, has been more than once.  The last continental glaciation in this part of the world, the Laurentide, resulted in an ice sheet that buried the spot where I'm now sitting under three hundred meters of ice, and dug out not only the nearby Finger Lakes but the Great Lakes.  The southern edge of the ice sheet created the Elmira Moraine, only thirty miles south of me -- a moraine is basically the debris left behind when a glacier recedes -- and also Long Island, the sand and gravel soils of which were shoved forward as the ice sheet pushed southward then left in place, much like the pile of snow left when a snowplow backs up (explaining its long, narrow shape).

So I shouldn't complain about the cold.  The era of the Laurentide Glaciation was a lot colder.  And in fact, there have been periods in Earth's history where everyone, not just people like who live in the frozen north, would have been in the icebox.

Our knowledge of this rather miserable time in the far distant past has, like so many discoveries, built by accretion.  In the 1870s and 1880s geologists found evidence of widespread glaciation in strata in Scotland -- then, more puzzlingly, in Australia and India.  Any deep understanding of this was hampered by the fact that back then, scientists thought the continents were firmly fixed in place; continental drift wasn't even first proposed until 1912, and then was soundly rejected until magnetometer data proved in 1958 that the tectonic plates were in constant motion.  The first evidence of a worldwide glaciation -- not just a big one, like the Laurentide -- was uncovered in 1964 by Cambridge University geologist W. Brian Harland, who showed that glacial strata in Svalbard and Greenland had been deposited in tropical latitudes.  Thus demonstrating two rather amazing conclusions in one fell swoop; first, that Svalbard and Greenland had moved a long way, and second, that at the time when they were near the equator, the whole world was covered with ice.

This "Snowball Earth" model has since been demonstrated as accurate in multiple ways.  More than once, but most significantly between 720 and 580 million years ago (i.e. the end of the Precambrian Era), the whole planet was covered with a kilometers-thick sheet of ice.  Picturing what this was like is a little mind-boggling.  The glaciers covered not only the land, but the entire ocean.  Because the liquid water underneath was moving, the ice sheets broke up and ground together, much like the rocky tectonic plates do today, floating on the liquid mantle of the Earth.  Any organisms caught in the cracks of the ice sheet, or between the glaciers and the seafloor, would have been pulverized.  "It’s basically like having a giant bulldozer," said Huw Griffiths, of the British Antarctic Survey, in an interview with Eos.  "The next glacial expansion would have just erased all [traces of life] and turned it into mush, basically."

Griffiths is the reason the topic comes up, actually; he, Rowan Whittle (also of the British Antarctic Survey), and Emily Mitchell (of the University of Cambridge) are the authors of a paper in The Journal of Geophysical Research that looked at the rare fossils that have survived since that time, and have drawn some fascinating parallels to species who survive today in similar conditions -- on the seafloor beneath the Antarctic Ice Sheets:

The timing of the first appearance of animals is of crucial importance for understanding the evolution of life on Earth.  Although the fossil record places the earliest metazoans at 572–602 Ma, molecular clock studies suggest a far earlier origination, as far back as ~850 Ma.  The difference in these dates would place the rise of animal life into a time period punctuated by multiple colossal, potentially global, glacial events...  The history of recent polar biota shows that organisms have found ways of persisting on and around the ice of the Antarctic continent throughout the Last Glacial Maximum (33–14 Ka), with some endemic species present before the breakup of Gondwana (180–23 Ma)...  [D]espite the apparent harshness of many ice covered, sub-zero, Antarctic marine habitats, animal life thrives on, in and under the ice.  Ice dominated systems and processes make some local environments more habitable through water circulation, oxygenation, terrigenous nutrient input and novel habitats...  The recent glacial cycle has driven the evolution of Antarctica's unique fauna by acting as a “diversity pump,” and the same could be true for the late Proterozoic and the evolution of animal life on Earth, and the existence of life elsewhere in the universe on icy worlds or moons.

One group of weird animals they looked at, which apparently thrived in these harsh conditions, were frondomorphs (Phylum Petalonamae), which are thought to have left no descendants whatsoever, and whose alliances to other animals are uncertain at best.

Fossil of a Precambrian frondomorph, Charniodiscus arboreus, from the Flinders Range in Australia [Image licensed under the Creative Commons tina negus from UK, Charniodiscus arboreus, CC BY 2.0]

These peculiar beasts were apparently anchored to the seafloor and absorbed nutrients and oxygen from the frigid waters through the feathery bits, but honestly, we know barely anything about how they made a living.  Some may have -- as many Antarctic sponges and sea anemones do today -- been affixed upside-down from the underside of the ice sheet.

These animals, nicknamed "extremophiles" for obvious reasons, just about all died out when things warmed up and the ice finally melted.  But it bears mentioning how long the Snowball Earth conditions persisted -- around 140 million years.  In other words, about the same amount of time as between the end of the Jurassic Period and now.   During that time, there were minor ups and downs, temperature-wise, but that's still a huge expanse of time during which the Earth was an ice-covered wasteland.

When the snowball finally did melt, and the cold-loving extremophiles such as Charniodiscus went extinct, it opened the door for one of the major events in the history of life on Earth -- the Cambrian explosion, when all of the main phyla of animals evolved in a relative flash.  But even when conditions were at their worst, life still survived, somehow.  The fact that life can thrive in apparently hostile conditions improves our chances of finding it elsewhere in the universe, and cheers me up significantly with regards to the weather we're currently having here.

It's also further support for the famous line from the inimitable Ian Malcolm in Jurassic Park: "Life, uh, finds a way."

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