Science bias

I come on pretty strongly in favor of science most of the time.  While I try to temper my obvious pro-science stance with an admission that the scientists are only human and therefore fallible, I've been known to use phrases like "the only game in town" with respect to science as a pathway to knowledge.

It may be, however, that I'll have to tone it down a little, considering a study that appeared in eNeuro last week.  Entitled, "Why Is It So Hard to Do Good Science?", by Emory University professor of pharmacology Ray Dingledine, this paper posits that science is inherently susceptible to confirmation bias -- the very thing the scientific method was developed to control.

[Image is in the Public Domain]

Dingledine's claim is that scientists introduce bias into experiments inadvertently because their preconceived notions about what they think they're going to find alter how they approach the question -- all the way down to the level of what equipment they use.  James Burke pointed this out, in his wonderful series The Day the Universe Changed.  "At this stage, you're looking for data to support your theory, so you design instruments to find the kind of data you reckon you're going to find," Burke says.  "The whole argument comes full circle when you get the raw data itself.  Because it isn't raw data.  It's what you planned to find from the start."

A lot of scientists bristle at this kind of criticism, and point out examples of scientists finding data that didn't fit the existing model, resulting in the model being overhauled or thrown out entirely.  Burke does as well; he cites plate tectonics, a model that arose from magnetometer data from the ocean floor that couldn't be explained with the understanding of geology at the time.

But the thing is, those instances stand out precisely because they're so uncommon.  Major revisions of the model are actually really infrequent -- which a lot of us rah-rah-science types have celebrated as a vindication that the scientific approach works, because it's given us rock-solid theories that have withstood decades, in some cases centuries, of empirical work.

Dingledine poniards that idea neatly.  He writes:

“Good science” means answering important questions convincingly, a challenging endeavor under the best of circumstances.  Our inability to replicate many biomedical studies has been the subject of numerous commentaries both in the scientific and lay press.  In response, statistics has re-emerged as a necessary tool to improve the objectivity of study conclusions. However, psychological aspects of decision–making introduce preconceived preferences into scientific judgment that cannot be eliminated by any statistical method.

It's possible to counter this tendency, Dingledine says, but not in any sense easy:

The findings reinforce the roles that two inherent intuitions play in scientific decision-making: our drive to create a coherent narrative from new data regardless of its quality or relevance, and our inclination to seek patterns in data whether they exist or not.  Moreover, we do not always consider how likely a result is regardless of its P-value.  Low statistical power and inattention to principles underpinning Bayesian statistics reduce experimental rigor, but mitigating skills can be learned.  Overcoming our natural human tendency to make quick decisions and jump to conclusions is a deeper obstacle to doing good science; this too can be learned.

Which just shows that bias runs deeper, and is harder to expunge, than most of us want to admit.

Now, I'm not meaning for anyone to switch from scientific experimentation to Divine Inspiration or whatnot.  Nor am I saying that any of the Big Ideas -- the aforementioned plate tectonics, the Newtonian/Einsteinian model of physics, quantum mechanics, molecular genetics, evolution by natural selection -- are wrong in any kind of substantive way.  It's more that we can't afford to get cocky.  What happens when you get cocky is you miss things, including the effect your preconceived notions have on your outlook.

So all of us could use a dose of humility, not to mention self-awareness.  The take-home message here is that we shouldn't take ideas as truthful out of hand, and should be especially wary if they agree with what we already thought was true.  We're all prone to confirmation bias -- and that includes the smartest amongst us.

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This week's Skeptophilia book recommendation is a charming inquiry into a realm that scares a lot of people -- mathematics.  In The Universe and the Teacup, K. C. Cole investigates the beauty and wonder of that most abstract of disciplines, and even for -- especially for -- non-mathematical types, gives a window into a subject that is too often taught as an arbitrary set of rules for manipulating symbols.  Cole, in a lyrical and not-too-technical way, demonstrates brilliantly the truth of the words of Galileo -- "Mathematics is the language with which God has written the universe."

The Illuminati visit Denver

In today's episode of How Not To Deal With Conspiracy Theorists, we have: the people who run the Denver Airport claiming that all the conspiracy theories about the place are actually true.

Controversy has been swirling around Denver International Airport for some time now.  Long-time readers of Skeptophilia may recall that two years ago, a loon named William Tapley who calls himself "The Third Eagle of the Apocalypse" (he doesn't specify what happened to Eagle #1 and Eagle #2) said he believed that Donald and Melania Trump were both being controlled by the Illuminati, and he knows this because of a mural in the Denver Airport featuring a woman who looks vaguely like Melania.

But that's only the merest fraction of what's been claimed about the airport.  And to be fair, there's some weird stuff there.  First, there's a horse statue out front that has LED eyes and is really freakin' creepy, and also for some reason bright blue.  Supposedly, the horse statue collapsed on its creator shortly after completion and killed him, and that led to the claim that the statue is cursed.

The horse's name?

"Blucifer."

And as crazy as Tapley is, I have to admit he has a point about the murals.  I mean, when you're rushing to catch a plane, and feeling frustrated and irritable, you wouldn't want to see this:

Or maybe that's just me.  Maybe some air passengers would see this and think, "Okay, maybe my flight has been delayed six hours and I haven't had anything to eat all day but a stale packet of pretzels and now I'm going to be lodged for three hours in a seat that would be cramped for a small child, but at least I'm not being threatened with a scimitar by a Nazi wearing a gas mask."

Anyhow, there were all these ideas floating around that the people who run the airport were in league with the Powers of Darkness, or with the New World Order at the very least.  Some people said that hidden beneath the airport is a portal to hell.  (All I can say is in the "hell" category, Denver Airport is never going to beat Chicago-O'Hare.)  And instead of saying, "Look, will y'all just calm down?  None of this is true," the folks in the airport have been playing it up.

In an area that's under renovation, there are some signs like, "Under construction?  Or... underground tunnels?"  Another one said:

What are we doing?
A) Adding amazing new restaurants and bars
B) Building an Illuminati headquarters
C) Remodeling the lizard people’s lair

"I think that we recognize that conspiracy theories are part of our brand," airport spokesperson Emily Williams told the Denver Post.  "It’s a fun way that we can engage with our passengers."

All I can say is: you don't know these conspiracy theorists.

By playing in, they're going to have every conspiracy theorist in the world thinking that the Illuminati are getting cocky and bragging about how their plans for world domination are going.  The idea that the powers-that-be in Denver are making fun of them would never occur to them.  Conspiracy theorists, in general, are completely unfamiliar with the concept of Poe's Law. 

On the other hand, it's kind of a losing battle anyway.  If you do what the Denver Airport people are doing, which is to say, "Yes, you're right.  We're evil Satanic Illuminati who are trying to destroy the Earth, bwa ha ha ha ha ha," the conspiracy theorists will say, "See?  I told you so!"  If instead you were to say, "Don't be a bunch of nimrods.  We have an airport to run, we have far more pressing issues to attend to than creating portals to hell," the conspiracy theorists will answer, "Of course that's what you would say.  Your denial means you're covering up something."

So you can't win.  But I still don't think it's a good idea to give them more ammunition.  Probably the wisest course of action would be to lay low and go about business as usual, and hope that the conspiracy theorists choose another activity, such as picking at the straps of their straitjackets with their teeth.

But I guess all hope of that ended when they put up the statue of Blucifer.  So what the hell, may as well have a little fun, I guess.

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

Insect rebound

I vividly recall my first visit to the American Museum of Natural History in Washington, DC, perhaps fifteen years ago.  Having a fascination for evolutionary biology and paleontology, I was thrilled to take a walk down the hallway with exhibits of each biological taxon, in phylogenetic order -- put simply, all the groups of living things in the order they come on the family tree of life.

So I'm walking up the hall, and things are progressing the way I'd expect -- bacteria to protozoans to plants to primitive animals, and within Kingdom Animalia, jellyfish to flatworms to roundworms to more complex invertebrates, and then on to fish, amphibians, reptiles, birds, and mammals.

But that wasn't the end of the hall.  The usual approach to the "Great Tree of Life" -- with, of course, mammals at the top of the heap and humans at the top of the mammals, as befits the pinnacle of evolution -- wasn't applied here.  If you progress past mammals, you're into Phylum Arthropoda, those animals with jointed legs and an exoskeleton, which include arachnids, crustaceans, centipedes, millipedes, and the most successful creatures on Earth...

... insects.

Being that it's the end of summer in upstate New York, I can verify that insects are highly successful life forms, given that there are millions of mosquitoes in my back yard alone, every single one of which divebombs my wife whenever she goes outside.  Something about Carol just attracts biting insects.  In fact, she claims that I bring her along to tropical destinations just to draw the mosquitoes away from me.

Which is not true.  Honestly.

In all seriousness, there is incredible diversity amongst insects, and many taxonomists believe that the number of insect species outnumbers all other kinds of animals put together.  Just beetles by themselves -- Order Coleoptera -- represents over 400,000 species, or about 25% of the total animal biodiversity on Earth.

This is the origin of the famous story about biologist J. B. S. Haldane, who was not only a vocal proponent of evolution but was an outspoken atheist.  Haldane frequently had hecklers show up at his talks, and one such asked him at the end, "So, Professor Haldane, what has your study of biology told you about the nature of God?"

Without missing a beat, Haldane replied, "All I can say is that he must have an inordinate fondness for beetles."

Metallic Shield Bug (Scutiphora pedicellata) from Australia [Image licensed under the Creative Commons Benjamint444, Metallic shield bug444, CC BY-SA 3.0]

It's curious that such a diverse and ubiquitous group still has a great many questions unresolved about its origins.  It's known that the big jump in insect diversity came after the Permian-Triassic Extinction of 252 million years ago, the "Great Dying" that wiped out (by some estimates) 95% of life on Earth.  There's a common pattern that a sudden burst of species formation always follows a mass extinction, but in this case, because of a poor fossil record following the event, it's been hard to connect later biodiversity to speciation amongst the survivors.

We just got a huge boost in what we know about insect evolution because of the discovery of a fossil deposit in China dating from 237 million years ago, or only ("only!") fifteen million years after the extinction itself.  The site had eight hundred fossils representing 28 different insect families that had survived the bottleneck, including the ancestors of modern beetles, flies, and cockroaches.

The study, done jointly by Zheng Daran and Wang Bo of the State Key Laboratory of Paleobiology and Stratigraphy in Nanjing, China and Chang Su-Chin of the University of Hong Kong, is only a preliminary analysis of the fossils at the site, and has already helped to connect the dots between pre-Permian-Triassic insects and more modern ones.  As Elizabeth Pennisi, senior correspondent for Science magazine, writes:

The sites underscore that this burst of evolution took place much earlier than researchers had thought, particularly for water-loving insects.  Among the remains are fossil dragonflies, caddisflies, water boatmen, and aquatic beetles.  Until now, paleontologists had thought such aquatic insects didn’t diversify until 130 million years ago.  These insects—which include both predators and plant eaters—helped make freshwater communities more complex and more productive... moving them toward the ecosystems we see today.

It's always fascinating when we add something to our knowledge of past life, and even more impressive when it's about one of the most diverse groups that has ever existed.  Seeing how life rebounded after the Permian-Triassic Extinction should also give us hope -- that even after a cataclysm, the survivors can still come back and rebuild Earth's biodiversity.

Or, as Ian Malcolm put it in Jurassic Park, "Life finds a way."

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

Notes from the multidimensional realm

In today's episode of Missives From Insane People Who Still Somehow Get A National Platform, we have: Paul McGuire, self-styled "End Times author," who appeared last week on the Jim Bakker Show.

It bears mention that Bakker himself is nuttier than squirrel shit.  Bakker, you may remember, is the one who predicted a couple of years ago that we atheists were imminent to start publicly beheading Christians.  As of right now, my total is a shameful Zero Christians Beheaded, which either means Bakker is a fucking loon or else I'm way behind on my Decapitation Quota.

Then, last year, Bakker railed against liberals for "blaspheming against Donald Trump."  Direct quote, that, despite the fact that the Merriam-Webster Dictionary of English says that "blaspheme" means "to speak irreverently about God or sacred things."  Which elevates Trump just slightly beyond his station.  Oh, and if that weren't enough, Bakker's also the one who claimed that the U. S. government was being run by witches.

So it's not like Bakker himself is exactly a pinnacle of normality.  But his guest, Paul McGuire, makes Bakker look like Mr. Sane Rationality 2018 by comparison.

Although it bears mention that Bakker treated everything McGuire said as if it were revealed truth, so maybe they're not that far apart after all.

In any case, here's what McGuire had to say:

President Trump is currently engulfed in the greatest spiritual battle in the history of all mankind...   The physical battles that we see in our world and nation right now are a direct manifestation of the spiritual battles going on in the invisible realm...  There are people very high up in what is called the globalist occult or globalist Luciferian rulership system, and this rulership system consists of what used to be called the Pharaoh-God Kings, it’s what Aldous Huxley called "The Scientific Dictatorship," and these are advanced beings who know how to tap into supernatural multidimensional power and integrate it with science, technology, and economics. 

The highest level of the pyramidic organizational structure in which the highest ranking officers, if you will, of the New World Order and Mystery Babylon are ruling the earth through an organizational structure that looks like the pyramid on the back of the U.S. dollar.  And they control the world because they understand that the true control of the world is done through supernatural mechanisms.

So there you have it.

You know, I have to admit that if I were a Luciferian multidimensional being in charge of Mystery Babylon, I would definitely use my supernatural Pyramid Powers to smite the shit out of Donald Trump.  It may seem petty of me, and there are probably more worthy targets, but I'd love to use occult magic to seal his mouth shut.  Or make it so every time he tweets, no matter what he writes, it comes out "I [heart] the New World Order."  Or attach a thousand-watt LED to his forehead that lights up every time he tells a lie.

Of course, it'd be lit so often that it'd interfere with air traffic.  So that'd be bad.

Looks like Lucifer has been hitting the gym lately.  (Fallen Angel, Alexandre Cabanel, 1847) [Image is in the Public Domain]

But what strikes me about McGuire's claim is that despite all of his dire warnings... nothing is happening.  Trump is still in office, his toadies in Congress are looking like they've greased the rails for Brett "Documents Withheld" Kavanaugh to be appointed to the Supreme Court, and the administration as a whole has undone decades of progress on environmental and social issues without anyone being able to stop them, or even slow them down.  So if there really are Luciferian multidimensional beings, I would be really glad if they'd get off their asses and do something about this.  Because it's increasingly looking like we've invented time travel, and transported the entire nation back to 1830.

In any case, that's the view from the lunatic fringe for today.  Now, y'all'll have to excuse me, because I'm late for a meeting of the Pyramidic Organizational Structure.  I hope one of the other Invisible Realm Operatives brings donuts.

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

Elegy for a treasure trove

I've always felt a very visceral sense of loss.  Even breaking a valued keepsake, for example, strikes me as sad by virtue of being irreversible, and triggers in me something that feels very much like mourning.

The bigger the loss, of course, the harder the gut punch.  I still have a vivid memory of finding out about the burning of the Library of Alexandria in 48 B.C.E., and carrying around with me a feeling very close to horror for several days afterward.  (Especially since many historians believe that the fire was deliberately set by soldiers sent to Egypt by Julius Caesar.)  The result of the fire was a devastating loss of cultural knowledge -- no one knows how many scrolls and books were destroyed, but even conservative estimates are in the range of forty to fifty thousand, most of which were the only copies in existence.

And some historians have said that the figure might have been closer to four hundred thousand.

The Great Library of Alexandria (1886, woodcut by Otto von Corven) [Image is in the Public Domain]

Entirely lost were the works of Hipparchus (the "father of astronomy"), and the majority of the creative output of the playwrights Aeschylus, Sophocles, and Euripides.  Only one-third of the writings of Archimedes survive -- the other two-thirds were housed in the Library and were destroyed when it burned.

And that's just a few of the ones we know about.

I felt that same sense of crushing desolation two days ago when I heard about the destruction of the Brazilian National Museum in Rio de Janeiro while listening to NPR.  The fire -- whose cause is, as of the time of this writing, uncertain -- completely destroyed the museum and its contents, although there's still some hope that a few of the more fireproof items may have survived.  The impact on scholarship can't be exaggerated; several of the scientists who were interviewed were obviously trying to hold back tears while talking about it.

According to an article by National Geographic, the museum, founded in 1818, housed twenty million items relating to a wide variety of disciplines.  There was the 11,500-year-old skull of Luzia, the oldest human skeletal remains ever found in Brazil.  There were specimens of forty thousand different species of mollusks and five million species of arthropods.  The museum also had South America's most extensive collection of Egyptian artifacts -- almost certainly all destroyed.

"When I saw the news about the tragedy, I just started crying, and all my colleagues, other archaeologists I know in Brazil, they had the same reaction—that’s a loss for all the world," said Maria Ester Franklin Maia Silva, a Brazilian archaeologist and Ph.D. student at the University of São Paulo.

Silva isn't alone.  Marcus Guidoti, an entomologist nearing completion of his Ph.D. at the Federal University of Rio Grande do Sul, has witnessed the loss of the entire collection his research relied on.  And anthropologist Mariana Françozo, of Leiden University, was equally devastated. "I have no words to say how horrible this is.  The indigenous collections are a tremendous loss…we can no longer study them, we can no longer understand what our ancestors did.  It’s heartbreaking."

Fingers are already being pointed at the government for standing by and watching the Museu Nacional fall into disrepair, neglect which is almost certain to have contributed to the disaster.  The museum's fire safety precautions were nil, and there were no funds to amend it even had the directors wanted to.  Three years ago, they were forced to crowdfund money for repairing extensive termite damage -- because federal funding to repair the damage was repeatedly denied.

Brazilian president Michael Temer called the Museu Nacional's loss "incalculable to Brazil" and "a sad day for all Brazilians."  But Mariana Françozo wasn't impressed by his reaction.  "[My]... reaction is anger, because they knew the museum needed funding for years.  How do you ‘rebuild’ a 200-year-old collection that has burned to ashes?"

Whoever is at fault -- or even if the fire at the museum was entirely accidental -- reading about it leaves me feeling sick inside.  The loss to the wealth of human knowledge is enormous.  Like with the Library of Alexandria, the museum housed thousands of specimens that had yet to be studied, and whose destruction leaves a hole that can't ever be filled.

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

The child in the cemetery

It's astonishing how little a skeptical, rational approach has insulated me from having a purely visceral reaction sometimes.

I've commented to my wife that I seem to have two brains, and they don't talk to each other.  In fact, most of the time each one seems to be bound and determined that the other doesn't exist.  One is my rational brain, that tells me things like "You've been very healthy, all things considered, and the physical you had two days ago is really unlikely to have turned up anything even remotely questionable."  The other, my emotional brain, says, "You haven't gotten the results yet, which means that they are reluctant to tell you that you're dying of a rare, incurable, and horribly painful disease."

Even with less personal things, it's curious how I can have two completely independent reactions at precisely the same time.  Take, for example, the image captured on Google Street View in the Martha Chapel Cemetery, Huntsville, Texas last week.

How anyone thought of zooming in like this, on an image of a (supposedly) empty cemetery, I don't know.  At least that's my emotional brain speaking.  My rational brain says there's a clear reason -- because it's a hoax, a digitally-altered photograph.  But without further ado, here's the image in question:

If you'll look closely, there's a very convincing image of a little girl's face peeking from around the left side of the tree.

The link I provided shows the image in a variety of angles and magnifications, and also says that there's a second "ghostly image" in the picture.  You can see it in the rectangular space framed by the sapling and the two dark tree trunks on the left side of the image.  Here it is, magnified:

This one, on the other hand, just doesn't do it for me.  If you go to the link (the YouTube video it brings you to is only a minute and a half long), you can see it in even greater magnification, and it looks to me like...

... a leaf caught on the fence.  I don't see it as creepy enough to need further explanation; even considering pareidolia, the thing just doesn't look like a "human figure," but just a dark, irregular blob.

The little girl, though.  That one is, to put not to fine a point on it, freakin' creepy.  She even has a sly expression in her eyes.  I'm relatively certain it's not a ghost; I'll admit the possibility, but the likelihood of camera anomalies or an outright hoax is, in my opinion, far greater.

But my emotional brain doesn't agree.  My emotional brain, in fact, says it does not give a rat's ass about camera anomalies and hoaxes.  My emotional brain is saying, "OH DEAR GOD THAT'S A LITTLE GIRL GHOST AND THAT REALLY IS SCARY."

I'd like to be able to say that my rational brain wins the argument every single time, but truth be told, I am primarily an emotional creature -- odd, I know, for someone who is trained in science and who has waved the flag of rationalism at every opportunity.  In fact, I've often wondered if rationalism and skepticism appealed to me because it at least gave me some protection against going around having the screaming meemies every other Tuesday.

So it seems like I have to put up with having two personalities who give every evidence of hating each other's guts.  I guess it could be worse.  At least they don't get into verbal arguments.  Because people already think I'm eccentric enough without my going around acting like this guy.  Or these guys, depending on how you look at it.

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

Filling in the missing link

One of the chief values of science lies in its predictive power.

Once a theory has developed that accounts for all the known evidence, it then gives scientists new directions to pursue.  A classic example of this is Wolfgang Pauli's prediction in 1931 that there was a small, fast-moving particle that accounted for "lost" energy and momentum in beta decay (an example of which is the decay of carbon-14 into nitrogen-14).  Back then, they didn't have the technology to find it.  It took 28 years before Clyde Cowan and Fred Reines created a device that was able to detect it, and found a particle that had exactly the characteristics Pauli had predicted almost three decades earlier.  They named it the neutrino.

When this kind of thing happens, it's a real vindication of the theory itself.  Of course, sometimes it goes the other way -- there'll be a discovery that contradicts some part of the theory.  This forces revision of the theory to account for the new information.  Thus science's other amazing strength: its ability to self-correct.  As physicist John Baez put it, "When you do theoretical physics, sometimes you feel the high of discovering hidden truths about the physical universe.  Sometimes you feel the agony of suspecting that those "hidden truths" were probably just a bunch of baloney... or, realizing that you may never know.  Ultimately nature has the last word."

We had a nice example of that just this past week, not in physics but in evolutionary biology, with the discovery of two new species of dinosaurs at digs in Mongolia and China.  The species, named Bannykus and Xiyunykus, connected up two groups of dinosaurs in the Alvarezsauridae, which had tube-like snouts with tiny teeth, compact hands with narrow fingers and sharp claws, and (from the site of muscle attachment points on the skeleton) apparently had powerful pectoral muscles.  (You might guess, correctly, that they're thought to be allied to the earliest birds.)

The hand bones of Bannykus [photograph by Jonah Choiniere, University of Witwatersrand, South Africa]

The problem was, there were alvarezsaurids from the late Jurassic Period, 150 million years ago, and some from the late Cretaceous, 70 million years ago -- and nothing in between.  That's a pretty sizable gap.  These "missing link" situations are common enough.  Unsurprising, given how unlikely it is for a fossil to survive intact for hundreds of millions of years, not even considering how tricky fossil formation is in the first place.  The truth is that only a minuscule fraction of the species that have existed left fossils -- the lion's share of the biodiversity Earth has had is unknown and probably unknowable.

It must be said at this juncture that "missing links" do not cast evolution into doubt.  To quote Carl Sagan, "Absence of evidence is not evidence of absence."  But because paleontology, like any good science, develops theories with predictive value, you can make some guesses about what should be there in those gaps.

And last week, we had another example of evolutionary biology and paleontology making a prediction that was spot-on.  "When we see a transition like that in the fossil record, we always want to know how it happened," said Corwin Sullivan in an interview with CBC.   Sullivan, a professor of paleontology at the University of Alberta, co-authored the paper, titled "Two Early Cretaceous Fossils Document Transitional Stages in Alvarezsaurian Dinosaur Evolution," which appeared in the journal Current Biology.  "[T]hese animals are, in a sense, missing links," Sullivan said.  "The teeth are quite a bit smaller — and in particular in the alvarezsaurids of the late Cretaceous, which are usually interpreted as specialized for insect eating, the teeth get very small, they lose their serrations on a very fine scale...  It's probably a question of exploiting a food resource that was available.  They would have been competing with other theropods and other kinds of predators."

Which is pretty cool.  It's always nice when the scientists say, "Hey, based on what we know, this must exist," and presto, someone finds exactly what they predicted.  Maybe the specifics in this case would only be of interest to serious dinosaur nerds, but the bigger picture -- that science can allow us not only to analyze what we have hard evidence of, but to infer detailed information about the missing pieces when we don't -- is pretty inspiring.

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This week's Skeptophilia book recommendation is part hard science, part the very human pursuit of truth.  In The Particle at the End of the Universe, physicist Sean Carroll writes about the studies and theoretical work that led to the discovery of the Higgs boson -- the particle Leon Lederman nicknamed "the God Particle" (which he later had cause to regret, causing him to quip that he should have named it "the goddamned particle").  The discovery required the teamwork of dozens of the best minds on Earth, and was finally vindicated when six years ago, a particle of exactly the characteristics Peter Higgs had described almost fifty years earlier was identified from data produced by the Large Hadron Collider.

Carroll's book is a wonderful look at how science is done, and how we have developed the ability to peer into the deepest secrets of the universe.

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