Thawing the snowball

One of the frightening things about a system in equilibrium is what happens when you perturb it.

Within limits, most systems can recover from perturbation through some combination of negative feedbacks.  An example is your body temperature.  If something makes it goes up -- exercise, for example, or being outside on a hot, humid day -- you sweat, bringing your temperature back down.  If your body temperature goes down too much, you increase your rate of burning calories, and also have responses like shivering -- which brings it back up.  Those combine to keep your temperature in a narrow range (what the biologists call homeostasis).

Push it too much, though, and the whole thing falls apart.  If your temperature rises beyond about 105 F, you can experience seizures, convulsions, brain damage -- or death.  Your feedback mechanisms are simply not able to cope.

This, in a nutshell, is why climate scientists are so concerned about the effects of anthropogenic carbon dioxide.  Within limits -- as with your body temperature -- an increase in carbon dioxide results in an increase in processes that remove the carbon dioxide from the atmosphere, and the whole system stays in equilibrium.  There is a tipping point, however.

The problem is that no one knows where it is -- and whether we may have already passed it.

A piece of research from the Virginia Polytechnic Institute, however, has suggested that this flip from stability to instability may be fast and unpredictable.  A paper authored by a team led by paleobiologist Shuhai Xiao, that was published in the journal Geology, looks at one of the main destabilization events that the Earth has ever experienced -- when the "Snowball Earth" thawed out in the late Precambrian Period, 635 million years ago.

Artist's conception of the Precambrian Snowball Earth [Image is in the Public Domain, courtesy of NASA/JPL]

Xiao and his team studied rocks from Yunnan and Guizhou, China, that are called cap carbonates.  They are made of limestone and dolomite and are deposited quickly in marine environments when the carbon dioxide content of the atmosphere spikes, leading to a dramatic temperature increase and a subsequent increase in absorption of carbonates into seawater (and ultimately deposition of those carbonates on the seafloor).  The cap carbonates Xiao et al. studied were dated to between 634.6 and 635.2 million years old, which means that the entire jump in both temperature and carbon dioxide content took less than 800,000 years.

So in less than a million years, the Earth went from being completely covered in ice to being subtropical.  The jump in global average temperature is estimated at 7 C -- conditions that then persisted for the next hundred million years.

Xiao et al. describe this as "the most severe paleoclimatic [event] in Earth history," and that the resulting deglaciations worldwide were "globally synchronous, rapid, and catastrophic."

Carol Dehler, a geologist at Utah State University, is unequivocal about the implications.  "I think one of the biggest messages that Snowball Earth can send humanity is that it shows the Earth’s capabilities to change in extreme ways on short and longer time scales."

What frustrates me most about today's climate change deniers is that they are entirely unwilling to admit that the changes we are seeing are happening at an unprecedented rate.  "It's all natural," they say.  "There have been climatic ups and downs throughout history."  Which is true -- as far as it goes.  But the speed with which the Earth is currently warming is faster than what the planet experienced when it flipped between an ice-covered frozen wasteland and a subtropical jungle.  It took 800,000 years to see an increase of the Earth's average temperature by 7 degrees C.

The best climate models predict that's what we'll see in two hundred years.

And that is why we're alarmed.

It's unknown what kind of effect that climate change in the Precambrian had on the existing life forms.  The fossil record just isn't that complete.  But whatever effect it had, the living creatures that were around when it happened had 800,000 years to adapt to the changing conditions.  What's certain is that an equivalent change in two centuries will cause massive extinctions.  Evolution simply doesn't happen that quickly.  Organisms that can't tolerate the temperature fluctuation will die.

We can only speculate on the effects this would have on humanity.

This is clearly the biggest threat we face, and yet the politicians still sit on their hands, claim it's not happening, that remediation would be too costly, that we can't prevent it, that short-term profits are more important than the long-term habitability of the Earth.  (Not to mention firing the people and closing the agencies that are currently trying to do something about it.)  Our descendants five hundred years from now will look upon the leaders from this century as having completely abdicated their responsibility of care for the people they represent.

Presuming we still have descendants at that point.

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Locks and guards

H. P. Lovecraft's novel The Lurker at the Threshold is, like much of his work, uneven.  At its best, it's atmospheric as hell, and has some scenes that will haunt your nightmares long after you turn the last page.  (I swear, I'll never look at a stained-glass window the same way after reading that book.)  It's the story of a man named Ambrose Dewart, who returns to rural Massachusetts after inheriting some property that had passed down in his family from a mysterious great-grandfather "whom no one in the family talked about."  Upon arrival, he reads a set of instructions that had come along with the deed, and finds a baffling warning that he should not damage a stone tower located nearby "lest he abandon his locks and guards."

It's a phrase that's peculiar and evocative, and it's stuck with me since I first read the tale when I was a teenager.  Especially since Ambrose proceeds to ignore the instructions entirely, knocks a hole in the tower so he can get inside, and unleashes chaos.

While overall it's a decent story, Dewart's actions always struck me as completely idiotic.  If you're in an unfamiliar situation, and you receive a set of ominous directives, why would you blunder in and do the exact opposite?  Especially when the implication is by doing so, you're getting rid of something that might be vital for protecting you?

I must say, though, that my sense that "no one would do something that stupid" may have to be revised, now that I've watched the last four weeks of actions by our so-called government here in the United States.

Just in the first month of Trump 2.0, he, Elon Musk, Pete Hegseth, Robert F. Kennedy Jr., and the various other lunatics in charge have:

• withdrawn the United States from the World Health Organization
• stripped funding from the Center for Disease Control and the National Institutes of Health, including ending research into cancer prevention and treatment
• proposed revoking the Affordable Care Act and making drastic cuts to Medicaid
• ended the CDC-led "Wild to Mild" flu vaccination campaign, just as flu-related hospitalizations reached a fifteen-year high of fifty thousand per week
• suggested that anyone on psychiatric medications, especially antidepressants and anxiolytics, should be taken off their medications and forced to go to mandatory "wellness camps"
• fired staff and cut funding to the National Oceanic and Atmospheric Administration, National Weather Service, and National Hurricane Center
• withdrawn the United States from the Paris Accords
• fired staff and cut funding to the National Parks Service
• fired senior staff in the military, replacing them with Trump loyalists
• fired all the Department of Energy staff who oversee nuclear weapons safety

When this last one got out, there was so much public outcry that the administration reversed course and tried to rehire the fired staff, with only partial success.  It turned out that the person responsible for the cuts was Luke Farritor, a 23-year-old SpaceX intern -- one of the techbro hackers Musk now has infiltrating the Department of Justice, the Social Security Administration, and the IRS.

And not one Republican congressperson has stood up and said no to any of it.  Sure, there are some who are probably loving every minute of this, like Marjorie Taylor Greene and the spectacularly stupid Nancy Mace.  The scuttlebutt is that a lot of them are horrified, but are "scared shitless" to say anything because they're afraid of reprisals by Trump and his goons. 

The media, too, has been largely complicit, for which you can thank people like Jeff Bezos and Patrick Soon-Shiong.  It's being played as "eliminating governmental waste and fraud," but make no mistake about it.  These cuts are not because they're examples of fraudulent spending.  You bring in auditors to find fraud, not hackers.  These decisions are being made purely for ideological reasons (when they're not just idiotic mistakes, like the firing of the nuclear weapons staff).  Epidemics and pandemics sound bad, and things like mandatory vaccinations and mask mandates don't sell well with the MAGA "don't step on muh freedoms" crowd, so no more funding the NIH and CDC.  Can't admit that anthropogenic climate change is happening, because it'll piss off Trump's BFFs in the fossil fuel industry, so destroy NOAA, the NWS, and the NHC.  The National Parks Service stands in the way of opening up the parks to mining, logging, and drilling for oil and natural gas, so they've gotta go.

And we have to make sure the military is led by Trump's christofascist cronies.  The firings went all the way up to the Chiefs of Staff, where Hegseth axed two -- Chief of Naval Operations Lisa Franchetti and Joint Chairman Air Force General C. Q. Brown, Jr.  Hmm... the only woman on the Chiefs of Staff, and the only Black guy.

Wonder what the motivation was there.

See why I thought about Lovecraft's book?  Trump has had over two centuries worth of precedent basically saying, "Here's how to keep our nation and its citizens as safe as possible," and his response was, "Okay, I'm going to do exactly the opposite of all that."

Not that this was probably his conscious thought.  There's a lot of speculation about his being a Russian agent, and working to destroy the United States deliberately, and I find that dubious.  Thing is, he isn't that smart.  His thinking never goes beyond (1) this will get people to praise me, (2) this make me richer, and (3) this will keep me out of jail.  It's more a case of running roughshod through the government to pad his own bank account and keep one step ahead of the people who might try to stop him.

Yeah, if it causes chaos in the United States, Vladimir Putin and Xi Jinping will be thrilled, but that's not why it started.  Trump is more a sticky-handed toddler loose in a museum.  He's likely to damage priceless stuff, but it's because he has the attention span of a gnat and zero impulse control, and throws hellacious tantrums when he doesn't get his way immediately.

[Image licensed under the Creative Commons Ritchie333, Trump Baby Balloon at protest in Parliament Square, CC BY-SA 4.0]

As far as the other people in charge -- well, Musk is in it for the money, although you have to wonder why four hundred billion dollars isn't enough for anyone.  Hegseth, Vance, and Noem are loony ideologues; of all of them, they're the ones most likely to be true believers.  As far as RFK, who the hell knows?  You look into that guy's dead eyes, and it's anyone's guess what's going on behind them.

Look, I understand that government isn't perfect.  Not ours, not any country's in the history of humanity.  There are porkbarrel projects and waste and cronyism, and probably at least some outright fraud.  But you don't fix it by running around with a chainsaw (which, I shit you not, Elon Musk literally did at CPAC last week).  What this represents is a coup by a coalition of fascists and burn-it-all-to-the-ground opportunists, who are using as their public face a man who has never had any thought beyond personal self-aggrandizement.

And in four weeks, we've abandoned -- no, destroyed -- our locks and guards.  Maybe it's not too late to put the pieces back together and keep the monsters from getting loose.  I don't know.  But the Republicans now in charge of both houses of Congress and the Supreme Court had damn well better figure out where their spines are and stop this.

Or in another four weeks we may not have a nation left to defend.

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Quantum pigeons

It will come as no particular shock to regular readers of Skeptophilia that I have a fascination for quantum physics.  Not that I can say I understand it that well; but no less than Nobel laureate and generally brilliant guy Richard Feynman said (in his lecture "The Character of Physical Law"), "If you think you understand quantum mechanics, you don't understand quantum mechanics."  I have a decent, if superficial, grasp of such loopy ideas as quantum indeterminacy, superposition, entanglement, and so on.  Which is why I find the following joke absolutely hilarious:

Heisenberg and Schrödinger were out for a drive one day, and they got pulled over by a cop. The cop says to Heisenberg, who was driving, "Hey, buddy, do you know how fast you were going?"

 
Heisenberg says, "No, but I know exactly where I am."

 
The cop says, "You were doing 85 miles per hour!"

 
Heisenberg throws his hands in the air and responds, "Great!  Now I'm lost."

 
The cop scowls at him.  "All right, pal, if you're going to be a smartass, I'm going to search your car."  So he opens the trunk, and there's a dead cat inside it.  He says, in some alarm, "There's a dead cat in your trunk."

 
Schrödinger says, "Well, there is now."

Thanks, you're a great audience. I 'll be here all week.

In any case, there's a recent paper in Proceedings of the National Academy of Sciences called, "Experimental Demonstration of the Quantum Pigeonhole Paradox," by a team of physicists at China's University of Science and Technology, which was enough to make my brain explode.  Here's the gist of it, although be forewarned that if you ask me for further explanation, you're very likely to get very little besides an expression of puzzled bewilderment, similar to the one my puppy gives me when I tell him something that is beyond his capacity to understand, such as why he should stop eating the sofa.

There's something called the pigeonhole principle in number theory, that seems kind of self-evident to me but apparently is highly profound to number theorists and other people who delve into things like sets, one-to-one correspondences, and mapping.  It goes like this: if you try to put three pigeons into two pigeonholes, one of the pigeonholes must be shared by two pigeons.

See, I told you it was self-evident.  Maybe you have to be a number theorist before you find these kind of things remarkable.

[Image licensed under the Creative Commons Razvan Socol, Rock Pigeon (Columba livia) in Iași, CC BY-SA 3.0]

In any case, what the recent paper showed is that on the quantum level, the pigeonhole principle doesn't hold true.  In the experiment, photons take the place of pigeons, and polarization states (either horizontal or vertical) take the place of the pigeonholes.  And when you do this, you find...

... that when you compare the polarization states of the three photons, no two of them are alike.

Hey, don't yell at me.  I didn't discover this stuff, I'm just telling you about it.

"The quantum pigeonhole effect challenges our basic understanding…  So a clear experimental verification is highly needed," study co-authors Chao-Yang Lu and Jian-Wei Pan wrote in an e-mail.  "The quantum pigeonhole may have potential applications to find more complex and fundamental quantum effects."

It's not that I distrust them or am questioning their results (I'm hardly qualified to do so), but I feel like what they're saying makes about as much sense as saying that 2 + 2 = 5 for large values of 2.  Every time I'm within hailing distance of getting it, my brain goes, "Nope.  If the first two photons are, respectively, horizontally polarized and vertically polarized, the third has to be either horizontal or vertical."

But apparently that's not true. Emily Conover, writing for Science News,writes:

The mind-bending behavior is the result of a combination of already strange quantum effects.  The photons begin the experiment in an odd kind of limbo called a superposition, meaning they are polarized both horizontally and vertically at the same time.  When two photons’ polarizations are compared, the measurement induces ethereal links between the particles, known as quantum entanglement.  These counterintuitive properties allow the particles to do unthinkable things.

Which helps.  I guess.  Me, I'm still kind of baffled, which is okay.  I love it that science is capable of showing us wonders, things that stretch our minds, cause us to question our understanding of the universe.  How boring it would be if every new scientific discovery led us to say, "Meh.  Confirms what I already thought."

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Pacific spike alert

One thing that drives me crazy is the tendency of the woo-woos to take a perfectly legitimate, valid piece of science, and then woo all over it.

The latest example of this is one you might have heard about.  Scientists doing isotopic analysis of cored sediments from the Pacific seabed found an unusual spike of an isotope called beryllium-10.  Beryllium-10 is mainly produced by cosmic rays colliding with oxygen and nitrogen atoms in the upper atmosphere; the beryllium atoms then gradually settle, creating what should be a uniform deposition in terrestrial and marine sediment layers.  Beryllium-10 is also radioactive, decaying into boron-10, so the relative concentrations of these two atoms, along with beryllium-10's known 1.4 million year half-life, allows for a convenient way to date sediment layers.

That, of course, presupposes that the formation and deposition rate of beryllium-10 is uniform, and cores from the Pacific seafloor from around ten million years ago show that, for a short time at least, this wasn't true.  These strata, from the mid-Miocene Epoch, showed up with an anomalous spike of beryllium-10.  What caused this isn't certain; two possibilities the researchers suggested were a shift in oceanic currents near Antarctica, causing an alteration in sediment distribution rate, or a nearby supernova producing a higher-than-normal influx of cosmic rays for a time.  In any case, the spike eventually leveled off, and the rest of the core sample was unremarkable, at least in that regard.

Well, "radioactive sediments" and "cosmic rays" and "anomaly" were apparently all it took.  In the past two weeks, since the paper was published, I've seen the following:

• the beryllium-10 spike is the debris from the reactor core of an exploded alien spacecraft, so add this to the list of "evidence for Ancient Astronauts."
• time-traveling government operatives went back to the Miocene to conduct illegal tests of nuclear superweapons so they could get away with it without anyone finding out, except apparently for this wingnut.
• the Sun had a "flare-up" ten million years ago that caused this.  This same phenomenon also caused all of the Earth's major mass extinctions.  It will happen again, and why is NASA covering this up?
• it's all a smokescreen to hide radioactive contamination that's actually from the Fukushima Reactor disaster.
• something something something HAARP something weather modification wake up sheeple something something.

Okay, will all of you lunatics just hang on a moment?

First of all, let's look at the actual spike the paper discusses.

[Image from Koll et al., Nature Communications, 10 February 2025]

See that wee bump at about ten million years?  That's the anomaly.  It's peculiar, sure, and cool that the scientists are trying to find out what caused it.  But it's a slightly higher-than-expected amount of a single isotope, and that's all.  They have even proposed some nifty uses for the discovery -- detecting the spike in sediment layers elsewhere could help to pinpoint how old they are -- but it's not, honestly, all that dramatic otherwise.  It doesn't correlate with a mass extinction (so cross out the Sun-induced extinction events), there are no other anomalous isotopes that show up at the same time (eliminating the superweapons and the ancient spacecraft, unless the aliens constructed their entire ship from beryllium-10), and it dates to ten million years ago (so it has nothing to do with Fukushima).

And HAARP was decommissioned in 2014, so all y'all conspiracy theorists can just shut the hell up about it, already.

I mean, really.  Isn't the actual science cool enough for them?  Why does everything have to fold into these people's favorite weird idea?

I suppose, as I saw a friend post a while ago, "Everything's a conspiracy if you don't understand how anything works."  But in these times when everyone's got a website, and "I read it on the internet" is considered by a lot of people to be the modern equivalent of "I have a Ph.D. from Cambridge in the subject," it's maddening how quickly these ideas spread -- and how little it takes for the wacko interpretations to eclipse the actual science.

So that's our dive into the deep end for today.  Beryllium spikes and ancient astronauts.  Me, I'm gonna stick with the scientific explanations.  Better than worrying about NASA covering up that we're all about to get fried by a "solar flare-up."

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Order out of chaos

When I was an undergraduate, I sang in the University of Louisiana Choir in a production of Franz Josef Haydn's spectacular choral work The Creation.

The opening is a quiet, eerie orchestral passage called "The Representation of Chaos" -- meant to evoke the unformed "void" that made up the universe prior to the moment of creation.  Then the Archangel Raphael sings, "In the beginning, God made Heaven and Earth; and the Earth was without form and void, and darkness was upon the face of the deep."  The chorus joins in -- everything still in a ghostly pianissimo -- "In the spirit, God moved upon the face of the waters; and God said, "Let there be light.  And... there... was...

...LIGHT!"

The last word is sung in a resounding, major-chord fortissimo, with the entire orchestra joining in -- trumpets blaring, tympanis booming, the works.  

Even if you don't buy the theology, it's a moment that sends chills up the spine.  (You can hear it yourself here.)

Of course, the conventional wisdom amongst the cosmologists has been that the universe didn't begin in some kind of chaotic, dark void; quite the opposite.  The Big Bang -- or at least, the moment after it -- is usually visualized as a searingly hot, dense fireball, which expanded and cooled, leading to a steady entropy increase.  So by our current models, we're heading toward chaos, not away from it.

Well, maybe.

A recent paper by the pioneering Portuguese physicist and cosmologist João Magueijo has proposed a new model for the origins of the universe that overturns that entire scenario -- and far from being ridiculed off the stage, he's captured the attention even of hard-nosed skeptics like Sabine Hossenfelder, who did a video on her YouTube channel about his paper a few days ago that is well worth watching in its entirety.  But the gist, as far as a layperson like myself can understand it, goes like this.

It's long been a mystery why the fundamental constants of physics have the values they do, and why they actually are constant.  A handful of numbers -- the speed of light, the strength of the electromagnetic interaction, the strength of the gravitational force, the fine-structure constant, and a few others -- govern the behavior of, well, pretty much everything.  None seem to be derivable from more fundamental principles; i.e., they appear to be arbitrary.  None have ever been observed to shift, regardless how far out in space (and therefore how far back in time) you look.  And what's curious is that most of them have values that are tightly constrained, at least from our perspective.  Even a percent or two change in either direction, and you'd have situations like stars burning out way too fast to host stable planetary systems, atoms themselves falling apart, or matter not generating sufficient gravity to clump together.

So to many, the universe has appeared "fine-tuned," as if some omnipotent deity had set the dials just right at the moment of creation of the universe to favor everything we see around us (including life).  This is called the anthropic principle -- the strong version implying a master fine-tuner, the weak version being the more-or-less tautological statement that if those numbers had been any different, we wouldn't be here to ask the question.

But that doesn't get us any closer to figuring out why the fundamental constants are what they are.  Never one to shy away from the Big Questions, that's exactly what Magueijo has undertaken -- and what he's come up with is, to put it mildly, intriguing.

What he did was to start from the assumption that the fundamental constants aren't... constant.  That In The Beginning (to stick with our original Book of Genesis metaphor), the universe was indeed chaos -- the constants could have had more or less any values.  The thing is, the constants aren't all independent of each other.  Just as numbers in our mundane life can push and pull on each other -- to give a simple example, if you alter housing prices in a town, other numbers such as average salaries, rates of people moving in and moving out, tax rates, and funding for schools will shift in response -- the fundamental constants of physics affect each other.  What Magueijo did was to set some constraints on how those constants can evolve, then let the model run to see what kind of universe eventually came out.

And what he found was that after jittering around for a bit, the constants eventually found stable values and settled into an equilibrium.  In Hossenfelder's video, she uses the analogy of sand grains on a vibration plate being jostled into spots that have the highest stability (the most resistance to motion).  At that point, the pattern that emerges doesn't change again no matter how long you vibrate the plate.  What Magueijo suggests is that the current configuration of fundamental constants may not be the only stable one, but the range of what the constants could be might be far narrower than we'd thought -- and it also explains why we don't see the constants changing any more.

Why they are, in fact, constant.

Stable pattern of grains on a vibrating pentagonal Chladni plate [Image licensed under the Creative Commons Matemateca (IME USP), Chladni plate 16, CC BY-SA 4.0]

Magueijo's work might be the first step toward solving one of the most vexing questions of physics -- why the universe exists with these particular laws and constants, despite there not seeming to be any underlying reason for it.  Perhaps we've been looking at the whole thing the wrong way.  The early universe really may have been without substance and void -- but instead of a voice crying "let there be light!", things simply evolved until they reached a stable configuration that then generated everything around us.

It might not be as audibly dramatic as Haydn's vision of The Creation, but it's just as much of an eye-opener.

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Kings of the jungle

When I visit New York City, one of my favorite places is, unsurprisingly, the American Museum of Natural History.  

And my favorite spot in that museum is the Hall of Mammals in the paleontology section.  I've always had a fascination for prehistoric mammals, especially those lineages that are extinct -- strange animals like the gargantuan brontotheres, the oddly rodent-like multituberculates, and the diverse South American hoofed litopterns.

Seeing all the dioramas of what these creatures may have looked like always highlights two things, which I was chatting about with a paleontologically-inclined friend a couple of days ago.  The first is that even though we know a great deal about Earth's biological history, there's a ton that we don't know and will probably never know.  Fossilization requires a very specific (and rare) set of conditions -- most organisms that die are never fossilized in the first place.  Then, those few fossils that form have to survive all of the geological processes that happen afterward, and not get eroded, melted, or crushed.  And last, a paleontologist (or interested amateur) has to find it.  So chances are, for every one species we know about, there are likely to be hundreds of others that we don't -- because the remains from those species haven't been found, or perhaps never were preserved in the first place.

Second, the natural world has often been a very, very dangerous place, with large quantities of animals with Big Nasty Pointy Teeth roaming around.  My friend and I both agreed that as fascinating as they are, neither of us would be keen on hopping into a time machine and visiting the Cretaceous-age Western Interior Seaway or the shallow sea that led to the Kem Kem Formation in what is now Morocco.  Both were chock-full of enormous BNPT-owners who would have been thrilled to turn any human-sized animal into a light snack.

Well, a recent discovery has added another place and time to the "Fascinating Spot, But Let's Not Visit, Mmmkay?" list: Oligocene-age Egypt.  It was the home of an extinct lineage of carnivorous mammals called hyaenodonts -- named after, but only distantly related to, modern hyenas -- in particular one spectacularly scary beast called Bastetodon, a complete skull of which was the subject of a paper last week in The Journal of Vertebrate Paleontology.  

Study lead author Shorouq Al-Ashqar of Mansoura University, along with the Bastetodon skull (and a statue of the Egyptian goddess Bastet, after which the species was named) [Image credit photographer Hesham Sallam]

The skull was found in a fossil-rich stratum in the Faiyum Depression, a green oasis in central Egypt surrounded by trackless desert.  During the Oligocene, Faiyum (and the rest of northern Africa) was a lush jungle, and Bastetodon and the other hyaenodonts were apex predators, preying not only on the hippos and elephants of the time, but on primates like Aegyptopithecus -- a close cousin of our own ancestors, who evolved farther south in what is now Kenya and Tanzania.

Bastetodon was brilliantly equipped to fill its niche.  "I think of them as like really beefy wolverines or basically like pitbulls," said Matthew Borths, of Duke University, who co-authored the paper.  "They have really big heads that were just covered in muscle."

That, combined with an impressive set of BNPTs, made it a fearsome animal, but it bears mention that it wasn't the largest of the hyaenodonts.  That honor goes to Megistotherium osteothlastes -- the name is Greek for "giant bone-crushing beast" -- which is estimated to have weighed five hundred kilograms, with a sixty-centimeter-long skull.

Yeah, fascinated as I am with prehistoric mammals, I think Oligocene-age north Africa is a place I'd just as soon not visit.

Interestingly, though, not long after Bastetodon and Megistotherium reached their apogee, the entire group went into steep decline.  No one is quite sure why, but it's probably that climate change had a lot to do with it.  The region was getting hotter and drier, reducing the amount of vegetation and ultimately producing the desert we have now.  These sorts of changes percolate their way up the food chain, ultimately hitting carnivores the hardest; the last of the hyaenodonts went extinct during the Miocene Epoch.  (Even bigger changes were on the way, however -- during the Pliocene Epoch, the Straits of Gibraltar closed for a time, the Mediterranean Sea dried up almost completely, and the entire region became so hot it was uninhabitable -- then when the Straits reopened, it created a flood the likes of which is nearly impossible to imagine.)  

But for a while, when northern Africa was lush jungle, the hyaenodonts were on the top of the heap.  There was nothing that could come close to matching their strength and fierceness, until the climate and the passage of time ended their hegemony.  Just showing that no species is immortal -- and that today's powerful are tomorrow's (pre)historical footnote.

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Misremembering the truth

There are two distinct, but similar-sounding, cognitive biases that I've written about many times here at Skeptophilia because they are such tenacious barriers to rational thinking.

The first, confirmation bias, is our tendency to uncritically accept claims when they fit with our preconceived notions.  It's why a lot of conservative viewers of Fox News and liberal viewers of MSNBC sit there watching and nodding enthusiastically without ever stopping and saying, "... wait a moment."

The other, dart-thrower's bias, is more built-in.  It's our tendency to notice outliers (because of their obvious evolutionary significance as danger signals) and ignore, or at least underestimate, the ordinary as background noise.  The name comes from the thought experiment of being in a bar while there's a darts game going on across the room.  You'll tend to notice the game only when there's an unusual throw -- a bullseye, or perhaps impaling the bartender in the forehead -- and not even be aware of it otherwise.

Well, we thought dart-thrower's bias was more built into our cognitive processing system and confirmation bias more "on the surface" -- and the latter therefore more culpable, conscious, and/or controllable.  Now, it appears that confirmation bias might be just as hard-wired into our brains as dart-thrower's bias is.

I recently read a paper that shed some light on this rather troubling finding in Human Communication Research, describing a study conducted by a team led by Jason Coronel of Ohio State University.  In "Investigating the Generation and Spread of Numerical Misinformation: A Combined Eye Movement Monitoring and Social Transmission Approach," Coronel, along with Shannon Poulsen and Matthew D. Sweitzer, did a fascinating series of experiments that showed we not only tend to accept information that agrees with our previous beliefs without question, we honestly misremember information that disagrees -- and we misremember it in such a way that in our memories, it further confirms our beliefs!

The location of memories (from Memory and Intellectual Improvement Applied to Self-Education and Juvenile Instruction, by Orson Squire Fowler, 1850) [Image is in the Public Domain]

What Coronel and his team did was to present 110 volunteers with passages containing true numerical information on social issues (such as support for same-sex marriage and rates of illegal immigration).  In some cases, the passages agreed with what (according to polls) most people believe to be true, such as that the majority of Americans support same-sex marriage.  In other cases, the passages contained information that (while true) is widely thought to be untrue -- such as the fact that illegal immigration across the Mexican border has been dropping for years and in the last five years has been at its lowest rates since the mid-1990s.

Across the board, people tended to recall the information that aligned with the conventional wisdom correctly, and the information that didn't incorrectly.  Further -- and what makes this experiment even more fascinating -- is that when people read the unexpected information, data that contradicted the general opinion, eye-tracking monitors recorded that they hesitated while reading, as if they recognized that something was strange.  In the immigration passage, for example, they read that the rate of immigration had decreased from 12.8 million in 2007 to 11.7 million in 2014, and the readers' eyes bounced back and forth between the two numbers as if their brains were saying, "Wait, am I reading that right?"

So they spent longer on the passage that conflicted with what most people think -- and still tended to remember it incorrectly.  In fact, the majority of people who did remember wrong got the numbers right -- 12.8 million and 11.7 million -- showing that they'd paid attention and didn't just scoff and gloss over it when they hit something they thought was incorrect.  But when questioned afterward, they remembered the numbers backwards, as if the passage had actually supported what they'd believed prior to the experiment!

If that's not bad enough, Coronel's team then ran a second experiment, where the test subjects read the passage, then had to repeat the gist to another person, who then passed it to another, and so on.  (Remember the elementary school game of "Telephone?")  Not only did the data get flipped -- usually in the first transfer -- subsequently, the difference between the two numbers got greater and greater (thus bolstering the false, but popular, opinion even more strongly).  In the case of the immigration statistics, the gap between 2007 and 2014 not only changed direction, but by the end of the game it had widened from 1.1 million to 4.7 million.

This gives you an idea what we're up against in trying to counter disinformation campaigns.  And it also illustrates that I was wrong in one of my preconceived notions; that people falling for confirmation bias are somehow guilty of locking themselves deliberately into an echo chamber.  Apparently, both dart-thrower's bias and confirmation bias are somehow built into the way we process information.  We become so certain we're right that our brain subconsciously rejects any evidence to the contrary.

Why our brains are built this way is a matter of conjecture.  I wonder if perhaps it might be our tribal heritage at work; that conforming to the norm, and therefore remaining a member of the tribe, has a greater survival value than being the maverick who sticks to his/her guns about a true but unpopular belief.  That's pure speculation, of course.  But what it illustrates is that once again, our very brains are working against us in fighting Fake News -- which these days is positively frightening, given how many powerful individuals and groups are, in a cold and calculated fashion, disseminating false information in an attempt to mislead us, frighten us, or anger us, and so maintain their positions of power.

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