A rare firecracker

A layperson might be excused if looking up at the night sky, (s)he concluded that other than slight variations in color and brightness, one star is pretty much like another.

I can't deny they look that way.  Even with the best telescope available to amateur astronomers, stars are featureless points of light.  About all we earthbound amateurs could discern that might clue us in to stars' wide variety of features, compositions, and behaviors is that some (many of them, in fact) are in binary or multiple star systems, and that a few fluctuate in brightness at regular intervals.  (Variable stars, in fact, were known to the ancients, and because in general our ancestors felt that the heavens should be eternal and changeless, they were viewed with great suspicion; one of the best-known, in fact, is Algol, which comes from the Arabic words for "the ghoul's head.")

First with the Hubble Space Telescope, and now with the James Webb Space Telescope, we've finally gotten the first direct photographs of stars showing any kind of detail (and the first direct photographs of exoplanetary systems).  But astrophysical data collection, often in regions of the electromagnetic spectrum the eye can't see, has given us more information about the wild variety of stars out there -- many of which are only now beginning to be understood.

Take for example the binary star system with the euphonious name CPD-29-2176, located a bit over eleven thousand light years away.  This pair is so strange that its characteristics are thought to match only one in every ten billion star systems, meaning there are probably only ten or so of them in the entire Milky Way.  (Fortunate, then, that one is close enough to study.)  First discovered from its x-ray signature by NASA's Neil Gehrels Swift Observatory and later studied by the SMARTS 1.5-meter Telescope, CPD-29-2176 is a kilonova progenitor system -- a pair of stars in which one is destined to blow up.

Artist's impression of CPD-29-2176  [Image courtesy of CTIO/NOIRLab/NSF/AURA/J. da Silva]

The mechanism is a little like a type 1a supernova, in which a white dwarf is in a close orbit with a larger main-sequence star.  The white dwarf, a dense, hot stellar nucleus of a moribund star, slowly draws off material from it partner through its intense gravitational pull, creating a whirlpool of accreting matter.  This, however, can only go on so long; once the white dwarf exceeds the Chandrasekhar limit, about 1.4 solar masses, it suddenly collapses.  The temperature skyrockets, and the former white dwarf becomes a supernova intense enough to blow the companion right out of orbit.

Here, though, the dynamics are a bit different.  If a supernova is a "holy shit!" event, a kilonova is more of a "meh."  What apparently is happening is the two stars are already so close that one is losing material to the other at a colossal rate.  The result: once the losing star burns through its fuel, at which point it should undergo the collapse/explosion cycle, there won't be enough fuel left to spike its temperature much.  It will trigger a kilonova (also called an ultra-stripped supernova), which is to an actual supernova what a wet firecracker is to a nuclear bomb.

What's even more interesting is that the same fate is predicted for the companion star; ultimately, what will be left is two neutron stars whirling around a common center of gravity, eventually falling inward and coalescing.  The release of gravitational potential energy by the merger will tear the stars apart -- stunning this could happen to objects so dense -- and the resulting debris, highly enriched in heavy elements, will be dispersed to the cosmos.

As astonishing as it sounds, all of the heavy elements -- the gold and silver in our jewelry, the mercury in our thermometers (well, old ones, at least), the uranium in our nuclear power plants, the rare earth elements in our computers -- were created in the cores of dying stars.  (If you want to learn more about this astonishing process, I did a piece here at Skeptophilia about it a couple of years ago.)

While a kilonova isn't going to be anything spectacular to watch from here on Earth, it's a rara avis indeed in the galactic zoo.  

Every time I read about some new astronomical discovery, it highlights for me how much more complex the universe is than the ancients dreamed.  Their point sources of light on crystal spheres, driven by deities and heavenly powers, miss the true intricacy of the cosmic clockwork by light years.  How delighted Galileo and Copernicus and Eratosthenes would be to know what we know -- to get a glimpse of a universe so vast, and so diverse, that it far surpasses the famous quote by Shakespeare -- "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."

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The unanswerable

Humans are boundlessly curious, and that's a good thing.  Our drive to understand, to cure our ignorance about the world around us, is the engine that powers science.  In my 32-year career as a science teacher, one of the things I strove the hardest to accomplish was to urge my students never to be content to shrug their shoulders and stop trying to understand.

Like most things, though, this curiosity has a downside, and that is when it turns into a desperation to have an answer, any answer, whether it's supported by the evidence or not.  Saying "I don't know, and may never know" is sometimes so profoundly uncomfortable that we settle into whatever explanation sounds superficially appealing -- and forthwith stop thinking about it.

Taking a scientific, skeptical view of things requires not only that you have the drive to understand, but that you can tolerate -- and know the scope of -- the limits of your own knowledge.  As theoretical physicist John Archibald Wheeler put it, "We live on an island surrounded by a sea of ignorance.  As the island of our knowledge grows, so does the shore of our ignorance."

What got me thinking about this is a story I ran into on the site Coast to Coast, which specializes in oddball speculation about unexplained phenomena.  The headline was "Mysterious Stone Carving Stumps Archaeologists in England," just the latest in umpteen popular media stories about some new discovery that "has scientists baffled."

To read this stuff, you come away with the impression that scientists do nothing all day but sit around scratching their heads in puzzlement.

In any case, the contents of the story are interesting enough.  A curious stone carving was discovered by some archaeologists investigating a Late Bronze Age site on Nesscliffe Hill, near Shrewsbury.  Without further ado, here's the carving:

Paul Reilly, one of the archaeologists studying the site, said that the carving is "indicative of two different types of technology, grinding and carving...  It appears to depict some kind of figure with the indentation being its head and the various scratches representing two long horns and two small horns, a central body line and two arms, one held up and the other down, the upward one showing a possible hand holding a pipe or a weapon...  Placing it in historical context, however, is another challenge altogether...  The carving has similarities with Late Bronze Age carvings of figures in horned helmets.  The region was once the domain of a Roman tribe known as the Cornovii, a name that has been suggested to reference to the ‘horned ones’.  The figure also could represent a horned deity cult in the Roman army as depicted at several military sites across Britain."

Note how many times Reilly uses words like "appears" and "could be" and "possible" and "suggested."  The fact is -- as he admits up front -- he doesn't know who carved the figure and why.  Dating such finds is a challenge at best, and this one is especially problematic; it was found in loose soil that had been used to backfill a trench from an earlier dig, so it was not in what archaeologists call "a secure context" (i.e., pretty much where it had been placed when its maker set it down millennia ago).

None of this is all that unusual; this kind of thing happens all the time in archaeology, and is in fact way more common than finding an artifact and being able to ascertain exactly when it had been created, by whom, and why.  But what got me thinking about our need to find an answer, any answer, was how Tim Binnall -- who wrote the article about the discovery -- wound up his piece by asking if any of his readers could "solve the mystery of the stone carving," and asked them to submit their answers to him at Coast to Coast.

Now, I know part of this is just an attempt to engage his readers, and there's nothing wrong with that.  I always love it when readers post comments and questions here at Skeptophilia (well, almost always -- I could do without the hate mail).  But immediately I read that, my reaction was, "Why on earth would some random layperson's opinion on the carving have any relevance whatsoever?"  He is, in essence, asking people to form opinions about an artifact for which even the experts have nothing more than speculation.

This is where we cross over into the territory of preferring any answer at all over admitting that we simply don't know, and may never know.

I'm deliberately leaving this in the realm of an obscure archaeological find, because (notwithstanding Binnall's request) few of us are going to get passionately emotional about a carved piece of rock from Bronze Age England.  But I'm sure you can come up with lots of other, more highly charged, examples of this -- questions for which our desire to have answers overrides the fact that we simply don't have enough evidence to conclude anything.  And some of these answers to unanswerable questions are believed with enough fervor that people will die for them -- and there are those who will unhesitatingly kill you if your answer is different from theirs, or worse, if you state outright that you don't know, and in reality, neither do they.

These are not easy issues.  As I said earlier, a lot of it comes from a source that is, at its heart, a positive thing; the drive to know.  But honesty is as important as curiosity, and that includes an honest assessment of what we understand and what we do not.  I'll conclude with a quote from another brilliant physicist, Richard Feynman: "I would far rather have questions that cannot be answered than answers that cannot be questioned."

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Signals of interest

Usually, when people think about finding extraterrestrial intelligence, they think of radio transmissions -- a trope that has been the basis of dozens of movies and television shows (Contact and Starman immediately come to mind).  Just two days ago I looked at a new approach to detecting biosignatures -- traces of living things, usually in the context of life on other planets -- which involved arguments having to do with complex biochemistry.

Then yesterday, I ran into a new study from the SETI (Search for Extraterrestrial Intelligence) Project describing a recently-developed deep learning technique which goes back to radio astronomy -- and that has already uncovered eight "signals of interest" from previously-analyzed radio telescope data.

Now, before we go any further, allow me to state up front that no one (well, no one credible) is saying any of these signals actually come from you-know-who. 

Don't get your hopes up quite yet.

But this finding does give us alien enthusiast types some hope for answering the Fermi paradox -- "If life is common in the universe, where is everyone?" -- with two rejoinders: (1) we've only studied a vanishingly small slice of the star systems even in our own galaxy; and (2) our previous techniques for analyzing the radio emissions of the systems we have studied still missed some signals that by previously-accepted criteria should warrant a closer look.

All eight signals of interest shared the following three characteristics that put them in the "curious" column:

1. They were narrow-band -- i.e. only peak at a narrow range of frequencies.  Radio signals from natural sources tend to be broad-band.
2. They had non-zero drift rates, meaning they were not moving with the same speed as the observatory.  This rules out terrestrial sources, a constant source of interference with radio telescope data.
3. The signals occurred only at specific celestial coordinates, and the intensity fell off rapidly when the telescope moved from being aimed at those coordinates.

All of these are features you would expect from radio transmissions from an extraterrestrial intelligence.

"In total, we had searched through 150 terabytes of data of 820 nearby stars, on a dataset that had previously been searched through in 2017 by classical techniques but labeled as devoid of interesting signals," said Peter Ma of the University of Toronto, who was lead author of the paper, which appeared in Nature Astronomy.  "We're scaling this search effort to one million stars today with the MeerKAT telescope and beyond.  We believe that work like this will help accelerate the rate we're able to make discoveries in our grand effort to answer the question 'are we alone in the universe?'"

I'm delighted astronomers are continuing to push forward with the search for extraterrestrial intelligence.  They certainly could be forgiven for giving up, considering the fact that since the SETI Institute was founded in 1984, they have yet to find anything that has convinced scientists.  Even with arguments like the one I made in my post two days ago, that purely statistical arguments like the Drake equation suggest that life is common in the universe, the complete lack of hard evidence would certainly be sufficient justification for scientists to put their efforts elsewhere.

That they haven't done so is a tribute not only to their dogged determination, but the importance of the question.  Not only would finding extraterrestrial life (or even better, intelligence) have profound implications for our understanding of astronomy, biochemistry, and biology, it would create seismic shifts in everything from anthropology to theology.  Such a finding would fundamentally and permanently alter our perception of the universe and our own place in it.

Myself, I think that'd be a good thing.  Our species needs period reminders that we're not all that and a bag of crisps.  Finding out that we're only one intelligent species of many would further emphasize that we don't occupy the center of the universe in any sense -- and, hopefully, reinforce our sense of wonder at the forces that have produced life and intelligence not only here on Earth, but throughout the myriad galaxies.

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Reversing the core

I get really frustrated with science news reporting sometimes.

I mean, on the one hand, it's better that laypeople get exposed to science somehow, instead of the usual fare of the mainstream media, which is mostly stories about seriously depressing political stuff and the latest antics of celebrities.  But there's a problem with science reporting, and it's the combination of a lack of depth in understanding by the reporters, and a more deliberate desire to create clickbaity headlines and suck people in.

Take, for example, the perfectly legitimate (although not universally accepted) piece of research that appeared on January 23 in Nature Geoscience, suggesting that the Earth's inner core oscillates in its rotational speed with respect to the rest of the planet -- first going a little faster, then slowing a bit until its rotational rate matches Earth's angular velocity, then slowing further so the rest of the planet for a time outruns the core.  Then it speeds up, and does the whole thing in reverse.  The reason -- again, if it actually happens, which is still a matter of discussion amongst the experts -- is that the speed-up/slowdown occurs because of a combination of friction with the outer core, the effects of the magnetic field, and the pull of gravity from the massive mantle that lies outside it.

[Image licensed under the Creative Commons CharlesC, Earth cutaway, CC BY-SA 3.0]

That's not how this story got reported, though.  I've now seen it several times in different mainstream media, and universally, they claim that what's happening is that the inner core has stopped, and started to spin the other way -- i.e. the inner core is now rotating once a day, but in the opposite direction from the rest of the Earth.

This is flat-out impossible.  Let's start with the fact that the inner core has a mass of about 110,000,000,000,000,000,000,000 kilograms.  A mass that huge, spinning on its axis once a day, has a stupendous amount of angular momentum.  To stop the rotation of that humongous ball of nickel and iron would take an unimaginable amount of torque, and that's not even counting overcoming the drag that would be exerted by the outer core as you tried to make the inner core slow down.  (I could calculate how much, but it's just another huge number and in any case I don't feel like it, so suffice it to say it's "a shitload of torque.")  Then, to accelerate it so it's rotating at its original rate but in the opposite direction would take that much torque again.

Where's the energy coming from to do all that?

Here, the fault partly lies with the scientists; they did use the words "reversing direction" in their press release, but what they meant was "reversing direction with respect to the motion of the rest of the Earth."  I get that relative motion can be confusing to visualize -- but giving people the impression that something has stopped the inner core of the Earth and started it rotating in the opposite direction gives new meaning to "inaccurate reporting."

Worse still, I'm already seeing the woo-woos latch onto this and claim that it's a sign of the apocalypse, that the Evil Scientists™ are somehow doing this deliberately to destroy the Earth, that it's gonna make the magnetic field collapse and trigger a mass extinction, and that it's why the climate has been so bonkers lately.  (Anything but blame our rampant fossil fuel use, apparently.)  Notwithstanding that if you read the actual paper, you'll find that (1) whatever this phenomenon is, it's been going on for ages, (2) it represents a really small shift in the inner core's angular velocity, and (3) it probably won't have any major effects on we ordinary human beings.  After all, (4) the scientists have only recently figured out it's happening, and (5) not all of them believe it is happening.

So let's just all calm down a bit, okay?

In any case, I'd really appreciate it if the people reporting science stories in the mainstream media would actually read the damn papers they're reporting on.  It'd make the job of us skeptics a hell of a lot easier.  Thanks bunches.

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Assembling aliens

There are a lot of hurdles in detecting extraterrestrial life, and that's not even counting the possibility that it might not exist.

Honestly, I don't think that last stumbling block is all that likely, and it's not just because proving we're not alone in the universe has been one of my dearest wishes since I was six years old and watching the original Lost in Space.  Since astronomer Frank Drake came up with his famous Drake equation in 1961, which breaks down the likelihood of extraterrestrial intelligence into seven individual parameters (each with its own, independent probability), the estimates of the values of those parameters have done nothing but increase.  As only one example, one of the parameters is f(p) -- the fraction of stars that have planetary systems.  When Drake first laid out his equation, astronomers had no certainty at all about f(p).  They were working off a sample size of one; we know the Solar System exists because we live in it.  But was its formation a fluke?  Were stars with planets extremely uncommon?

No one knew.

Now, exoplanet discovery has become so routine that it barely even makes the news any more.  The first exoplanet around a main-sequence star -- 51 Pegasi b -- was discovered in 1995.  Since then, astronomers have found 5,297 exoplanets, with new ones being announced literally every week.  It seems like damn near a hundred percent of stable main-sequence stars have planetary systems, and most of them have at least one planet in the "Goldilocks zone," where the temperatures are conducive to the presence of liquid water.

Even setting aside my hopes regarding aliens, the sheer probability of their existence has, from a purely mathematical standpoint based upon the current state of our knowledge of the universe, improved significantly.

But this still leaves us with a problem: how do we find it?  The distances even to the nearest stars are insurmountable unless someone comes up with warp drive.  (Where are you, Zefrem Cochrane?)  So we're left with remote sensing -- looking for biosignatures.  The most obvious biosignature would be a radio transmission that's clearly from intelligent life, such as the one Ellie Arroway found in Contact; but it bears keeping in mind that through almost all of the Earth's 3.7-billion-odd years it's been inhabited by living creatures, it would have been entirely silent.  Alien astronomers looking from their home worlds toward the Earth would not have heard so much as a whisper.  It's only since we started using radio waves to transmit signals, a century ago, that we'd be detectable that way; and given how much transmission is now done via narrow-beam satellite and fiber optics cables rather than simple wide-range broadcast, it's entirely possible that once the technology improves Earth will go silent once again.  There may only be a short period during which a technological civilization is producing signals that are potentially detectable from a long way away.

So the question remains: how could we determine if an exoplanet had life?

I'm guessing that whatever the aliens look like, it's not this.  Unfortunately.

The tentative answer is to look for other kinds of biosignatures, and the most obvious one is chemicals that "shouldn't be there" -- in other words, that would not form naturally unless there were life there producing them through its metabolic processes.  This, too, is not a simple task.  Not only is there the technological challenge of detecting what's in a distant exoplanet's atmosphere (something we're getting a lot better at, as spectroscopy improves), there's the deeper question of how we know what should be there.  If we find an odd chemical in a planet's atmosphere, how do we know if it was made by life, or by some exotic (but abiotic) chemistry based on the planet's composition and conditions?

We've gotten caught this way before; three years ago, scientists discovered traces of a chemical called phosphine in the atmosphere of Venus, and a lot of us -- myself included -- got our hopes up that it might be a biosignature of something alive in the clouds of our hostile sister planet.  The consensus now is that it isn't -- the amounts are vanishingly small, and any phosphine on Venus is a product of its wild convection and bizarre atmospheric makeup.  So once we detect a chemical on an exoplanet, is there a way to do a Drake-equation-style estimate of its likelihood of forming abiotically?

Astrobiologist Leroy Cronin, of the University of Glasgow, has proposed an answer, based on something he calls "assembly theory."  Assembly theory, significantly, doesn't rely on any kind of analogy to terrestrial life.  Cronin and others are now trying to figure out strategies to find life as we don't know it -- living creatures that might be based upon extremely different chemistry.

What he's done is given us a purely mathematical way to index chemicals according to how many independent steps it takes to create them from simple, pre-existing building blocks.  This molecular assembly number, Cronin says, is directly proportional to its likelihood of being created by a living thing.  As a simple analogy, he shows how you would find the molecular assembly number for the word abracadabra:

1. add a + b;
2. add ab + r;
3. add abr + a;
4. add abra + c;
5. add abrac + a;
6. add abraca + d;
7. add abracad + abra (we'd already created abra in step three).

Seven steps from the primordial building blocks, so the molecular assembly number for abracadabra is seven.

Replace putting letters and letter groups together with steps in a chemical reaction chain, and you have an idea how assembly theory works.

Like the Drake equation, Cronin's method isn't proof.  Finding some complex chemical in an exoplanet's atmosphere, the gas of a nebula, or a meteorite might be suggestive of life, but almost certainly wouldn't convince the doubters without a lot more in the way of evidence.  Still, just as Frank Drake did in 1961, it's nice to have a protocol for determining the likelihood of a biosignature that doesn't depend on our unavoidable Earth-centrism.  Like with the formation of the Solar System, we're familiar with only one kind of life -- the kind all around us, that we ourselves are examples of.  Shaking the bias that all life is Earth-like is not easy.

It's understandable that the creators of Lost in Space and Star Trek visualized almost all of the aliens as basically humans with odd facial excrescences, and that's granting the difficulty of finding a way to portray non-humanoid aliens convincingly using human actors.  When they did manage to get beyond humans with rubber noses, such as in the Lost in Space episode "The Derelict" and the Star Trek episodes "The Devil in the Dark" and "Obsession," the aliens were, respectively, giant mobile bubbles, a tunneling, acid-spewing rock, and a disembodied vampiric mist cloud, all of a which at least gave a shot at trying to visualize what truly non-Earthlike life might be.

I'm hopeful that the work of Cronin and others is moving the new field of astrobiology forward from simple "what ifs" to actual rigorous algorithms for analyzing the spectroscopic data we're gathering from exoplanet atmospheres.  And maybe... just maybe... within my lifetime we'll have enough data to feel confident we've identified for certain what I've been waiting for since I was six: life on another planet.

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The roots of conspiracy

It's all too easy to dismiss conspiracy theorists as just being dumb, and heaven knows I've fallen into that often enough myself.

Part of the problem is that if you know any science, so many conspiracy theories just seem... idiotic.  That 5G cell towers cause COVID.  That eating food heated up in a microwave causes cancer.  As we just saw last week, that Satan's throne is located in Geneva and that's why the physicists at CERN are up to no good.

And sure, there's a measure of ignorance implicit in most conspiracy theories.  To believe that Buffalo Bills player Damar Hamlin's on-field collapse was caused by the COVID vaccine -- as both Charlie Kirk and Tucker Carlson stated -- you have to be profoundly ignorant about how vaccines work.  (This claim led to a rash of people on Twitter who demanded that anything with mRNA in it be officially banned, apparently without realizing that mRNA is in every living cell and is a vital part of your protein-production machinery.  And, therefore, it is not only everywhere in your body, it's present in every meat or vegetable you've ever consumed.)

But simple ignorance by itself doesn't explain it.  After all, we're all ignorant about a lot of stuff; you can't be an expert in everything.  I, for example, know fuck-all about business and economics, which is why it's a subject I never touch here at Skeptophilia (or anywhere else, for that matter).  I'm fully aware of my own lack of knowledge on the topic, and therefore anything I could say about it would have no relevance whatsoever.

Scientists have been trying for years to figure out why some people fall for conspiracies and others don't.  One theory which at least partially explains it is that conspiracy theorists tend to score higher than average in the "dark triad" of personality traits -- narcissism, sociopathy, and black-and-white thinking -- but that isn't the whole answer, because there are plenty of people who score high on those assessments who don't espouse crazy ideas.

But now a psychologist at the University of Regina, Gordon Pennycook, thinks he has the right answer.

The defining characteristic of a conspiracy theorist isn't ignorance, narcissism, or sociopathy; it's overconfidence.

Pennycook designed a clever test to suss out people's confidence levels when given little to nothing to go on.  He showed volunteers photographs that were blurred beyond recognition, and asked them to identify what the subject of the photo was.  ("I don't know" wasn't an option; they had to choose.)  Then, afterward, they were asked to estimate the percentage of their guesses they thought they'd gotten right.

That self-assessment correlated beautifully with belief in conspiracy theories.

"Sometimes you're right to be confident," Pennycook said.  "In this case, there was no reason for people to be confident...  This is something that's kind of fundamental.  If you have an actual, underlying, generalized overconfidence, that will impact the way you evaluate things in the world."

The danger, apparently, is not in simple ignorance, but in ignorance coupled with "of course I understand this."  It reminds me of the wonderful study done by Leonid Rozenblit and Frank Keil about a phenomenon called the illusion of explanatory depth -- that many of us have the impression we understand stuff when we actually have no idea.  (Rozenblit and Keil's examples were common things like the mechanisms of a cylinder lock and a flush toilet, how helicopters fly and maneuver, and how a zipper works.)  Most of us could probably venture a guess about those things, but would add, "... I think" or "... but I could be wrong." 

The people predisposed to belief in conspiracy theories, Pennycook says, are the ones who would never think of adding the disclaimer.

That kind of overconfidence, often crossing the line into actual arrogance, seems to be awfully common.  I was just chatting a couple of weeks ago with my athletic trainer about that -- he told me that all too often he runs into people who walk into his gym and proceed to tell him, "Here's what I think I should be doing."  I find that attitude baffling, and so does he.  I said to him, "Dude, I'm hiring you because you are the expert.  Why the hell would I pay you money if I already knew exactly how to get the results I want?"

He said, "No idea.  But you'd be surprised at how often people come in with that attitude."  He shook his head.  "They never last long here."

The open question, of course, is how you inculcate in people a realistic self-assessment of what they do know, and an awareness that there's lots of stuff about which they might not be right.  In other words, a sense of intellectual humility.  To some extent, I think the answer is in somehow getting them to do some actual research (i.e. not just a quick Google search to find Some Guy's Website that confirms what they already believed).  For example, reading scientific papers, finding out what the actual experts have discovered.  Failing that -- and admittedly, a lot of scientific papers are tough going for non-specialists -- at least reading a damn Wikipedia page on the topic.  Yeah, Wikipedia isn't perfect, but the quality has improved dramatically since it was founded in 2001; if you want a quick overview of (for example) the Big Bang theory, then just read the first few paragraphs of the Wikipedia page on the topic, wherein you will very quickly find that it does not mean what the creationists are so fond of saying, that "nothing exploded and made everything."

Speaking of being overconfident on a topic about which they clearly know next to nothing.

In any case, I'll just exhort my readers -- and I'm reminding myself of this as well -- always to keep in mind the phrase "I could be wrong."  And yes, that applies even to your most dearly held beliefs.  It doesn't mean actively doubting everything; I'm not trying to turn you into wishy-washy wafflers or, worse, outright cynics.  But periodically holding our own beliefs up to the cold light of evidence is never a bad thing.

As prominent skeptic (and professional stage magician) Penn Jillette so trenchantly put it: "Don't believe everything you think."

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The swamps of Canada

Ellesmere Island would be high on the list of the Earth's most inhospitable places.

It's huge, only slightly smaller in area than Britain, and is part of the territory of Nunavut in Canada.  It is entirely above the Arctic Circle.  The record high temperature there was 15.6 C (60 F); the average high is 7 C (45 F).  The record low, on the other hand, is -47 C (-52.6 F).  It's also exceedingly dry, averaging a little over six inches of total precipitation a year.  It's no wonder that although the Inuit use some of it as summer hunting grounds, the permanent resident population stands at 144 brave souls.

Honestly, I'm a bit mystified as to why anyone lives there.

It wasn't always that way, though.  As hard as it is to fathom, Ellesmere Island used to be a swamp, back during the Paleocene-Eocene Thermal Maximum, a period about fifty-five million years ago during which the global average temperature was about eight degrees hotter than it is now.  The reasons it occurred are still a matter of discussion amongst climatologists, but from the chemistry and deposition of sedimentary rocks, it clearly came from a massive increase in the levels of atmospheric carbon dioxide, and was accompanied by the sea levels reaching levels between three hundred and four hundred meters higher than they are today.

If that happened now, where I'm currently sitting in upstate New York would be beachfront property.

What's most interesting about the climate of Ellesmere back then is that even though it was a warm swamp, it was pretty much located where it is today (i.e. above the Arctic Circle).  But even though for a couple of months of the year it was plunged into darkness, there were still trees -- fossils of the conifers Metasequoia and Glyptostrobus have been found in regions that now host little else besides mosses and lichens.

And a paper in PLOS-One this week showed that it isn't just subtropical trees that used to live on Ellesmere -- so did some long-lost cousins of primates.

We usually think of primates as being tropical, and for good reason; most of the primate species in the world live in areas not too far from the equator.  We originated there, too, of course; the ancestral home of Homo sapiens is Kenya and Tanzania (that's all humans -- sorry, racists).  We've since expanded our territory a little, but our relative hairlessness is a good indicator that we originally came from warmer climes.

But back during the PETM, Ellesmere was a warmer clime, and paleontologists have found in sedimentary rock strata the fossils of two proto-primates, Ignacius mckennai and Ignacius dawsonae.  The genus Ignacius is part of a much larger group called the plesiadapiforms, who are all extinct but whose closest living relatives are modern primates.  Ignacius was a genus confined to the northern half of North America, and when the temperatures warmed up and the forests spread north, Ignacius followed them.

This makes these remains the northernmost primate fossils ever found.

A reconstruction of Ignacius dawsonae [Image is licensed under the Creative Commons Kristen Miller/Biodiversity Institute/University of Kansas (CC-BY 4.0)]

What is amazing to me about this is... well... everything.  That trees could flourish in a swampy environment well above the Arctic Circle.  That non-human primates ever got this far north.  And most especially, that the Earth's climate was this drastically different, only fifty-five million years ago -- a long time ago on our usual timeline, but pretty much day before yesterday on the geological scale.

Of course, this should be a cautionary tale for us cocky humans, and probably won't be.  Things can change drastically.  Have changed drastically, and will again.  What we're doing right now is spiking the atmospheric carbon dioxide levels, and thus the temperature, at a far faster rate than just about anything in the geological record -- perhaps even exceeding the carbon dioxide pulse that set off the Permian-Triassic Mass Extinction.

And that cataclysm killed an estimated ninety percent of life on Earth.

All I can say is, we damn well better start paying attention, or else we'll find out that Santayana's famous quote about not learning from history also applies to not learning from prehistory.  Or, put more succinctly, that the best strategy is not "fuck around and find out."

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