The library of possibilities

In the brilliant Doctor Who episode "Turn Left," the Doctor's companion Donna Noble finds out that a single decision she made on a single day -- whether to turn right or left at an intersection -- creates two possible futures, one of them absolutely horrific.

It's a common trope in science fiction (although in my opinion, it's seldom been done as well, nor as poignantly, as in "Turn Left"), to look at how our futures could have been significantly different than they are.  I even riffed on this in one of my own novels -- Lock & Key -- in which there are not only multiple possible outcomes for each decision, there's a library (and a remarkably grumpy Head Librarian) that keeps track of not only what has happened, but what could have happened.  For every human being who ever existed, or who ever might have existed.

If you want to know how I handled the idea, you'll just have to read the book.

In reality, of course, the number of possible outcomes for even a simple series of choices increases exponentially with each successive decision, so in any realistic situation the possibilities are about as close to infinite as you can get.  Which makes a paper that came out in Nature last week even more extraordinary.

In order to see how amazing it is, a brief lesson in quantum mechanics for the non-physics-types in the studio audience.

One of the basic concepts in quantum physics is superposition: any measurable property of a wave (or subatomic particle) exists in multiple states at the same time.  The distribution of these states -- more specifically, the probability that the particle is in a specific state -- can be described by its wave function.  And the completely counterintuitive outcome of this model is that prior to observation, the particle is in all possible states at once, and only drops into a particular one (in a process called "collapsing the wave function") when it's observed.  (Regular readers of Skeptophilia may recall that I did a post on a particular part of this theory, Wigner's paradox, a few weeks ago.)

So that's amazing enough.  Particles and waves exist as a multitude of present possibilities, all at the same time.  But now, a collaboration between physicists at Griffith University (Queensland, Australia) and Nanyang Technological University (Singapore) have gone a step further:

They have developed a prototype device that generates a quantum state embodying all of the particle's future states simultaneously.

 My first thought was, "That can't possibly mean what it sounds like."  But yes, that turns out to be exactly what it means.  "When we think about the future, we are confronted by a vast array of possibilities," said Mile Gu of Nanyang Technological University, who led the study.  "These possibilities grow exponentially as we go deeper into the future. For instance, even if we have only two possibilities to choose from each minute, in less than half an hour there are 14 million possible futures.  In less than a day, the number exceeds the number of atoms in the universe."

So having even a simple system that generates all possible futures at the same time is somewhere beyond amazing, and into the realm of the nearly incomprehensible.

"Our approach is to synthesize a quantum superposition of all possible futures for each bias," said Farzad Ghafari, of Griffith University.  "By interfering these superpositions with each other, we can completely avoid looking at each possible future individually.  In fact, many current artificial intelligence (AI) algorithms learn by seeing how small changes in their behavior can lead to different future outcomes, so our techniques may enable quantum enhanced AIs to learn the effect of their actions much more efficiently."

"The functioning of this device is inspired by the Nobel Laureate Richard Feynman," added Dr Jayne Thompson, a member of the Singapore team.  "When Feynman started studying quantum physics, he realized that when a particle travels from point A to point B, it does not necessarily follow a single path.  Instead, it simultaneously transverses all possible paths connecting the points.  Our work extends this phenomenon and harnesses it for modeling statistical futures."

So I'm sitting here, trying to wrap my brain around the implication of this research.  Quantum indeterminacy indicates that we don't live in a completely deterministic universe; there's always some uncertainty, built into the actual fabric of the universe.  But the idea that we could, even in principle, create a system from which we could analyze all of the possible futures is stunning.

As Maggie Carmichael, the Assistant Librarian in Lock & Key, puts it:

All of our actions, even the smallest ones, make a difference.  Most of us never find out what that difference is.  All choices have consequences, however insignificant they seem at the time.  However, the truth of that statement is only evident here in the Library, where we can see what would have happened if we had acted otherwise.  Without that information, what happens simply… happens.

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This week's Skeptophilia book recommendation is a fun one; Atlas Obscura by Joshua Foer, Dylan Thuras, and Ella Morton.  The book is based upon a website of the same name that looks at curious, beautiful, bizarre, frightening, or fascinating places in the world -- the sorts of off-the-beaten-path destinations that you might pass by without ever knowing they exist.  (Recent entries are an astronomical observatory in Zweibrücken, Germany that has been painted to look like R2-D2; the town of Story, Indiana that is for sale for a cool $3.8 million; and the Michelin-rated kitchen run by Lewis Georgiades -- at the British Antarctic Survey’s Rothera Research Station, which only gets a food delivery once a year.)

This book collects the best of the Atlas Obscura sites, organizes them by continent, and tells you about their history.  It's a must-read for anyone who likes to travel -- preferably before you plan your next vacation.

(If you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!)

Whales, fossils, and the limitations of commons sense

One of my favorite things about science is its ability to jolt us out of our preconceived notions.

We all have common-sensical ideas about how the universe works, and they allow us to function pretty well most days.  The problem is, some of them are correct and some of them are wildly wrong, and how do you tell which is which?  As physicist Sean Carroll eloquently puts it, in his wonderful book The Particle at the End of the Universe:

It's only because the data force us into corners that we are inspired to create the highly counterintuitive structures that form the basis for modern physics...  Imagine that a person in the ancient world was wondering what made the sun shine.  It's not really credible to imagine that they would think about it for a while and decide, "I bet most of the sun is made up of particles that can bump into one another and stick together, with one of them converting into a different kind of particle by emitting yet a third particle, which would be massless if it wasn't for the existence of a field that fills space and breaks the symmetry that is responsible for the associated force, and that fusion of the original two particles releases energy, which we ultimately see as sunlight."  But that's exactly what happens.  It took many decades to put this story together, and it never would have happened if our hands weren't forced by the demands of observation and experiment at every step.

That's why I find it frustrating when someone says, "Oh, that can't be right, it sounds ridiculous," and forthwith stops thinking about it.  We've seen over and over that "sounding ridiculous" is not a reliable indicator of the truth of a claim.  The only acceptable criterion is hard evidence -- as long as you've got that, what your claim sounds like is entirely irrelevant.

This point comes up every year in my AP Biology class when we talk about the evolutionary history of whales.  The fossil record for whales was pretty lousy, because being marine mammals their skeletons are mostly destroyed by scavengers and degraded by seawater, not to mention the fact that many of them end up in the abyssal regions of the ocean floor.  After that, we'd only find them if those deep oceanic sediments get scooped up by the movement of tectonic plates and thrust up onto land -- something that (1) doesn't happen that often, and (2) results in significant deformation of the rocks formed, thus completely destroying any fossils that were present.

It wasn't until a fossil bed was discovered in Pakistan in the early 1980s that we actually got any data on what the ancestors of today's whales looked like.  The northern parts of Pakistan and India -- i.e., the Himalayas -- were formed in exactly the way I've described above.  We lucked out, though, because at least one rock formation not only has ancestral whale fossils, but ones that survived in reasonably good condition.

Now, here's the counterintuitive part; the fossils found in Pakistan and India have conclusively shown that the nearest living non-cetacean relatives of whales are hippos...

... and artiodactylid ruminants.  For example, cattle, sheep, goats, deer, and antelopes.

This is the point where people look at a picture of a blue whale and a white-tailed deer and say, "Hang on a moment.  That can't be right."  But it is -- as confirmed not only from the fossil record, but from extensive genetic studies.

We just got further confirmation of this relationship from an entirely different fossil bed -- this one from mid-Eocene (i.e., about forty million years old) rocks in Peru.  A team led by paleontologist Olivier Lambert, of the Institut Royal des Sciences Naturelles de Belgique, has discovered not only a new species but an entirely new genus of proto-cetaceans.  Called Peregocetus pacificus, it catches whale evolution right in the middle between the terrestrial ancestors and their aquatic descendants.

The authors write:

[T]his unique four-limbed whale bore caudal vertebrae with bifurcated and anteroposteriorly expanded transverse processes, like those of beavers and otters, suggesting a significant contribution of the tail during swimming.  The fore- and hind-limb proportions roughly similar to geologically older quadrupedal whales from India and Pakistan, the pelvis being firmly attached to the sacrum, an insertion fossa for the round ligament on the femur, and the retention of small hooves with a flat anteroventral tip at fingers and toes indicate that Peregocetus was still capable of standing and even walking on land.  This new record from the southeastern Pacific demonstrates that early quadrupedal whales crossed the South Atlantic and nearly attained a circum-equatorial distribution with a combination of terrestrial and aquatic locomotion abilities less than 10 million years after their origin and probably before a northward dispersal toward higher North American latitudes.

So that's kind of amazing.  It also illustrates why we can't rely on "that sounds reasonable" to determine what's true.  This is just one example of how science has come up with a result that we never would have arrived at using common sense -- as helpful as that is in most ordinary situations.

Reconstruction of ancestral cetacean Pakicetus inachus [Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com), Pakicetus BW, CC BY 3.0]

Myself, I like the capacity of science to astonish us.  It would be incredibly boring if the universe turned out to work exactly the way we thought, that our minds are perfect little windows through which we perceive everything right the first time.

Much better to be reminded of our limitations -- and to have such a powerful tool to check our guesses, and correct us when we're wrong.

***********************************

This week's Skeptophilia book recommendation is a fun one; Atlas Obscura by Joshua Foer, Dylan Thuras, and Ella Morton.  The book is based upon a website of the same name that looks at curious, beautiful, bizarre, frightening, or fascinating places in the world -- the sorts of off-the-beaten-path destinations that you might pass by without ever knowing they exist.  (Recent entries are an astronomical observatory in Zweibrücken, Germany that has been painted to look like R2-D2; the town of Story, Indiana that is for sale for a cool $3.8 million; and the Michelin-rated kitchen run by Lewis Georgiades -- at the British Antarctic Survey’s Rothera Research Station, which only gets a food delivery once a year.)

This book collects the best of the Atlas Obscura sites, organizes them by continent, and tells you about their history.  It's a must-read for anyone who likes to travel -- preferably before you plan your next vacation.

(If you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!)

Whispers, tingles, and brain orgasms

My wife sent me a link to an article a couple of days ago about a phenomenon that I'd heard a bit about, but never really researched.

It's called an "Autonomous Sensory Meridian Response," ASMR for short.  The nickname, though, is more telling; people call it a "brain orgasm."

Of course, on some level, all orgasms are about what happen in the brain.  fMRI studies of people during orgasm show that during arousal and climax people experience a surge of neurotransmitters like dopamine and endorphin, as well as the "cuddle hormone" oxytocin (explaining why most of us feel snuggly after doing the deed, not to mention sleepy).  Without a brain response, there's no arousal, and I think just about everyone can think of times when what was going on in their brains -- worry, fatigue, frustration, anger -- interfered with their desire, or even ability, to have sex.

Gustav Klimt, The Kiss (1908) [Image is in the Public Domain]

It brings up the question, however, of who is volunteering for those studies.  I mean, I'm as comfortable in my skin as the next guy, and in fact in my twenties would have been voted the captain of the co-ed skinnydipping team.  But doing a solo performance while hooked up to a fMRI, with lots of people wearing white lab jackets and holding clipboards and peering at me and taking notes, gives new meaning to the phrase, "no way, José."  I mean, if getting off with an audience turns you on, more power to you, but even with a significant cash incentive I don't think I'd participate.

But I digress.

Anyhow, my point is, there have been a good many studies of the neurochemistry of the human sexual response, so this ASMR thing is interesting because apparently for some people, hearing certain noises (or, less commonly, seeing particular images) triggers a brain response that is very similar to orgasm but without the involvement of your naughty bits.  Here's how one person describes it:

While watching videos of space... a tingling spreads through my scalp as the camera pulls back to show the marble of the earth.  It comes in a wave, like a warm effervescence, making its way down the length of my spine and leaving behind a sense of gratitude and wholeness.

The similarity to an actual orgasm is obvious.  But why was it happening?

Turns out, we don't know.  Also unknown is why the people who experience ASMR are (1) nearly all female, and (2) have particular triggers that are specific to them.  The article in the New York Times (linked above) said that there are five hundred new ASMR-inducing videos uploaded to YouTube every day, which I suppose is understandable given what they can allegedly do to you.  Most of them are some combination of people whispering, rubbing fabric or combs or the like across microphones, stroking rough surfaces with fingernails, crunching paper, brushing hair, or chewing food.

This last one was a little puzzling right from the get-go.  A lot of people hate the sound of others chewing.  My older son, for example, was as a teenager really sensitive to sounds like that, and became nearly homicidal when he was around someone eating Doritos.  But apparently not everyone responds that way, and some people feel exactly the opposite.

So I was intrigued, and got onto YouTube and checked out a couple of the videos.  Here's a typical one:

 I went into it figuring I wouldn't respond, given that I'm male, also was a little dubious from the outset, and...

... sure enough, nothing, or at least nothing positive.  In fact, I found the noises intensely annoying.  Not only was I not soothed or tingly, after about 45 seconds I wanted to climb out of my skin.  So if you watched the video and had a brain orgasm or whatever, I'm happy for you, but that was certainly not my experience.

It does bring up the fascinating question of how the same stimuli can provoke entirely different responses in different people.  And this applies outside of the realm of listening to people brush their hair, or even what specific things are a sexual turn-on; consider how unique people's reactions are to music.  My wife and I, for example, both love music, but what particular pieces of music grab us are completely different.  When I find a piece of music I love, it definitely gives me chills, and has been known to bring me to actual tears.  The first time I heard Vaughan Williams's Fantasia on a Theme by Thomas Tallis, for example, I ended up sobbing, and couldn't have explained why.

Now there's something I'd be willing to do while hooked up to a fMRI machine.

My point, though, is that these kinds of emotional and physical reactions are pretty common in humans, as is the fact that what specifically triggers them is highly personal.  I think we're a long, long way from figuring out why that is, though, even on the level of being able to comprehend as individuals why a particular trigger is a turn-on for us.

In any case, the whole ASMR thing is curious enough that it deserves more research.  It's understandable that scientists have been reluctant to do so, I suppose; both the variability of response, and the general oddity of the phenomenon, probably pushes researchers to look into phenomena that are more likely to get grant approval.  (In fact, the New York Times article said that there have only been ten academic papers addressing ASMR ever published.)

But given the popularity of the videos, there has to be something to it, and it'd be cool to find out what that something is.  So even if the sound of someone whispering or twisting bubble wrap or chewing gum doesn't turn me on, I'd sure like to know why it has that effect on others.

***********************************

This week's Skeptophilia book recommendation is a fun one; Atlas Obscura by Joshua Foer, Dylan Thuras, and Ella Morton.  The book is based upon a website of the same name that looks at curious, beautiful, bizarre, frightening, or fascinating places in the world -- the sorts of off-the-beaten-path destinations that you might pass by without ever knowing they exist.  (Recent entries are an astronomical observatory in Zweibrücken, Germany that has been painted to look like R2-D2; the town of Story, Indiana that is for sale for a cool $3.8 million; and the Michelin-rated kitchen run by Lewis Georgiades -- at the British Antarctic Survey’s Rothera Research Station, which only gets a food delivery once a year.)

This book collects the best of the Atlas Obscura sites, organizes them by continent, and tells you about their history.  It's a must-read for anyone who likes to travel -- preferably before you plan your next vacation.

(If you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!)

Tales from a white dwarf

This week we've focused on some cool scientific discoveries, which is, honestly, my happy place.  So we'll round out the week with a new piece of research that is kind of a double-edged sword.  It is (1) fascinating, but (2) tells us about how the Earth is going to be destroyed.  So while it's interesting, cheerful it isn't.

Of course, the upside is that the Earth isn't going to be destroyed for another few billion years.  So even in the best-case scenario, I won't be around when it happens.

The research was led by Christopher Manser of the University of Warwick, and is based on observations done of a white dwarf star at the 10.4-meter Gran Telescopio Canarias on La Palma in the Canary Islands.  White dwarfs are the remnants of stellar cores for stars smaller than about 10 times the mass of the Sun.  At the end of their lives, stars in this range exhaust the hydrogen fuel in their cores, and switch to burning helium -- this gives an added kick to the core temperature, and the outer atmosphere balloons out into what's called a red giant.  But eventually, it becomes a nova -- it exhausts the helium as well, the core collapses and heats up (dramatically), and that blows the outer atmosphere away (forming what's called a planetary nebula), in an expanding cloud of gas and dust surrounding the exposed core -- the white dwarf star.

[Image licensed under the Creative Commons, ESA/Hubble, Artist’s impression of debris around a white dwarf star, CC BY 4.0]

It was long thought that a star that becomes a white dwarf will in the process completely destroy any planets that happen to be orbiting around it.  When the Sun becomes a red giant, for example, it's believed that its outer edges will be somewhere between the orbits of Mars and Jupiter.  So where you are sitting right now will be inside the Sun.

I like it warm, but that's a bit toasty even my my standards.

So it was quite a shock when Manser et al. found that the white dwarf they were studying, the euphoniously named SDSS J122859.93+104032.9, had a planet orbiting it.

The fact that they could even tell that is pretty extraordinary.  As I explained in a previous post, the two most common ways of detecting planets are by occlusion (the star dimming because the planet has passed in front of it) or by Doppler spectroscopy (seeing shifts in the frequency of light from the star because it's being pulled around by the planet as it orbits).  Both of these work better when the planet is massive -- so for a little planet around a littler star, it's kind of amazing they even figured out it was there.

What they found was that there was light coming from the star system that was consistent with the emission spectrum of calcium, but oddly, the calcium spectral lines were split in two -- and the two lines oscillated back and forth with a period of almost exactly two hours.  The best explanation, say Manser et al, is that there is a planetesimal -- probably the iron-rich core of a planet that once orbited the star prior to its demise -- that is dragging around a cloud of calcium-rich gas that is being Doppler shifted first one way and then the other every time the planet circles the star.

As Luca Fossati, writing for Science magazine, describes the research:

The method of Manser et al. has revealed the presence of planetesimals without the need for the particular orbital geometry that is required by the transit method.  It could therefore be used to identify the presence of planetesimals orbiting other polluted white dwarfs and advance the study of the planetary systems evolution.  Furthermore, because planetesimals orbiting white dwarfs are believed to be the remnant cores of shattered planets, studying the spectra of polluted white dwarfs known to be surrounded by planetesimals enables one to gain information about the chemical composition and metal abundances of the infalling material—that is, planetary cores.

The most awe-inspiring part of this research is that this will be the likely fate of the Earth -- assuming that the red giant and nova phases of the Sun don't destroy it completely.  All that will be left is the remnant core of the Sun and the remnant core of the Earth, circling each other and gradually cooling, becoming a whirling pair of cinders forever spinning in the infinite dark, cold vacuum of space.

Have a nice day.

*****************************

This week's Skeptophilia book recommendation combines science with biography and high drama.  It's the story of the discovery of oxygen, through the work of the sometimes friends, sometimes bitter rivals Joseph Priestley and Antoine Lavoisier.   A World on Fire: A Heretic, an Aristocrat, and the Race to Discover Oxygen is a fascinating read, both for the science and for the very different personalities of the two men involved.  Priestley was determined, serious, and a bit of a recluse; Lavoisier a pampered nobleman who was as often making the rounds of the social upper-crust in 18th century Paris as he was in his laboratory.  But despite their differences, their contributions were both essential -- and each of them ended up running afoul of the conventional powers-that-be, with tragic results.

The story of how their combined efforts led to a complete overturning of our understanding of that most ubiquitous of substances -- air -- will keep you engaged until the very last page.

[Note:  If you purchase this book by clicking on the image/link below, part of the proceeds will go to support Skeptophilia!]

Snapshot of a very bad day

Some of you have probably bumped into articles in the last week or so about a phenomenal discovery in paleontology -- a fossil bed in North Dakota that may have been created the day the Chicxulub Meteor Strike occurred, 66 million years ago.  This single event is thought to have flash-fried everything in the southern half of what is now North America, changed climates worldwide, and was the death blow to the dinosaurs, with the exception of the lineage that led to modern birds.

The deposit contains exquisitely preserved remains of a variety of fish, plants, dinosaurs, and mollusks.  The gills of the fish contained huge numbers of tektites -- tiny spheres of glass formed during a meteorite collision and ejected into the atmosphere.  The impact is thought to have caused a magnitude 10 earthquake (almost unimaginable to me), which took the shallow ocean that crossed what is now the central United States and "agitated it like a washing machine" -- creating a seiche, a standing wave like the sloshing of water in a giant bathtub.

The seiche caused the repeated exposure and inundation of shallow regions, and while exposed, the stranded animals were subjected to a rain of tektites and other debris thrown up by the collision.

"This is the first mass death assemblage of large organisms anyone has found associated with the K-T boundary," Robert DePalma, curator of paleontology at the Palm Beach Museum of Natural History in Florida and a doctoral student at the University of Kansas, said in a press release.  "At no other K-T boundary section on Earth can you find such a collection consisting of a large number of species representing different ages of organisms and different stages of life, all of which died at the same time, on the same day."

One of the fish from the Hell Creek fossil bed

"The seismic waves start arising within nine to ten minutes of the impact, so they had a chance to get the water sloshing before all the spherules (small spheres) had fallen out of the sky," said Mark Richards, professor emeritus of earth and planetary science at the University of California - Berkeley.  "These spherules coming in cratered the surface, making funnels — you can see the deformed layers in what used to be soft mud — and then rubble covered the spherules.  No one has seen these funnels before...  You can imagine standing there being pelted by these glass spherules.  They could have killed you."

It's amazing to think that if these scientists are correct -- and the consensus amongst paleontologists is that they are -- we're seeing a remnant of a catastrophe initiated at a single moment in time.  The simulations of what happened are astonishing enough:

But somehow, to see the remains of animals that were directly killed by the collision, who were there when it happened, gives it an immediacy that is stunning.

So this is cool enough, right?  But what makes it even more personal for me is that one of the researchers who has worked the Hell Creek fossil bed, and was a co-author of the paper...

... is Loren Gurche, who is a former student of mine.

I distinctly remember Loren's contributions to my AP Biology class -- whenever the topic was prehistory, I always deferred to his greater knowledge.  Even then, when he was in 11th grade, he clearly knew way more paleontology than I did, or probably, than I ever would.  The presence of a true expert enriched both my experience and the other students', and it's thrilling to see that he is making significant contributions in a field about which he is so deeply passionate.

So the whole thing is doubly cool for me to read about.  I'm looking forward to more discoveries by Loren and the team he's working with, although it must be said it'll be hard to top this one.  This snapshot of one of the worst disasters ever to strike the Earth is the find of a lifetime.

*****************************

This week's Skeptophilia book recommendation combines science with biography and high drama.  It's the story of the discovery of oxygen, through the work of the sometimes friends, sometimes bitter rivals Joseph Priestley and Antoine Lavoisier.   A World on Fire: A Heretic, an Aristocrat, and the Race to Discover Oxygen is a fascinating read, both for the science and for the very different personalities of the two men involved.  Priestley was determined, serious, and a bit of a recluse; Lavoisier a pampered nobleman who was as often making the rounds of the social upper-crust in 18th century Paris as he was in his laboratory.  But despite their differences, their contributions were both essential -- and each of them ended up running afoul of the conventional powers-that-be, with tragic results.

The story of how their combined efforts led to a complete overturning of our understanding of that most ubiquitous of substances -- air -- will keep you engaged until the very last page.

[Note:  If you purchase this book by clicking on the image/link below, part of the proceeds will go to support Skeptophilia!]

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 new piece of research from the Virginia Polytechnic Institute has indicated that this flip from stability to instability may be fast and unpredictable.  A paper authored by a team led by paleobiologist Shuhai Xiao, that came out last month in 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.  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.

*****************************

This week's Skeptophilia book recommendation combines science with biography and high drama.  It's the story of the discovery of oxygen, through the work of the sometimes friends, sometimes bitter rivals Joseph Priestley and Antoine Lavoisier.   A World on Fire: A Heretic, an Aristocrat, and the Race to Discover Oxygen is a fascinating read, both for the science and for the very different personalities of the two men involved.  Priestley was determined, serious, and a bit of a recluse; Lavoisier a pampered nobleman who was as often making the rounds of the social upper-crust in 18th century Paris as he was in his laboratory.  But despite their differences, their contributions were both essential -- and each of them ended up running afoul of the conventional powers-that-be, with tragic results.

The story of how their combined efforts led to a complete overturning of our understanding of that most ubiquitous of substances -- air -- will keep you engaged until the very last page.

[Note:  If you purchase this book by clicking on the image/link below, part of the proceeds will go to support Skeptophilia!]

Buzzing off

I have great respect for scientists, which I hope is obvious from the content of this blog.  Even so, there are times I read scientific research and say, "What the hell were they thinking?"

That was my first thought when I read a BBC News article claiming that playing dubstep music by Skrillex makes mosquitoes less likely to bite and mate.  If you don't know who Skrillex is, that's probably a good thing if you've got reasonably refined musical sensibilities.  I try to be tolerant of other people's musical tastes and acknowledge that what you like is a matter of opinion, but it is my considered judgment that Skrillex sounds like a robot having sex with a dial-up modem.

So apparently what they apparently did is to play Skrillex for some mosquitoes, and the mosquitoes apparently didn't feel like eating or mating, which I have to admit is kind of the effect it has on me.  "[T]he occurrence of blood feeding activity was lower when music was being played," the scientists write.  "Adults exposed to music copulated far less often than their counterparts kept in an environment where there was no music...  The observation that such music can delay host attack, reduce blood feeding, and disrupt mating provides new avenues for the development of music-based personal protective and control measures against Aedes-borne diseases."

[Image licensed under the Creative Commons, Aedes aegyptii, photograph taken by Muhammad Mahdi Karim]

When I finished reading the article, my first thought was that this was a typical sensationalized report on scientific research, where popular media completely misrepresents what the scientists did in order to get clicks.  Sadly, this is not the case.  The BBC News actually did a pretty good job of describing the research -- it's just that the research was kind of... um... terrible.

Here's a piece from the paper itself, which appeared in Acta Tropica last week and is entitled,
"The Electronic Song 'Scary Monsters and Nice Sprites' Reduces Host Attack and Mating Success in the Dengue Vector Aedes aegypti," by a team of researchers led by Hamady Dieng of the University of Malaysia:

Sound and its reception are crucial for reproduction, survival, and population maintenance of many animals.  In insects, low-frequency vibrations facilitate sexual interactions, whereas noise disrupts the perception of signals from conspecifics and hosts.   Despite evidence that mosquitoes respond to sound frequencies beyond fundamental ranges, including songs, and that males and females need to struggle to harmonize their flight tones, the behavioral impacts of music as control targets remain unexplored. In this study, we examined the effects of electronic music ("Scary Monsters and Nice Sprites" by Skrillex) on foraging, host attack, and sexual activities of the dengue vector Aedes aegypti.   Adults were presented with two sound environments (music-off or music-on).  Discrepancies in visitation, blood feeding, and copulation patterns were compared between environments with and without music.  Ae. aegypti females maintained in the music-off environment initiated host visits earlier than those in the music-on environment.  They visited the host significantly less often in the music-on than the music-off condition.

Which is pretty much what the BBC News article said.

What's wrong with this research is that it falls into what I would call "so what?" studies.  It's the kind of thing that even if the protocols and controls were appropriate, doesn't tell you very much.  Okay, Skrillex screws up mosquitoes.  Why?  They only did "music on" and "music off;" they didn't try different kinds of music, various pure tones, harmonics, combinations of sounds, and other sorts of sounds.  So the outcome really gives us very little information about what's actually going on, and why -- nor how this could be used to reduce the spread of mosquito-borne diseases.

Because frankly, if I had a choice of getting dengue fever and listening to Skrillex all day, I'd have to think about it.

So anyhow, I guess having a paper in a scientific journal doesn't necessarily guarantee that the research it describes isn't kind of silly.  And it also highlights the importance of going from the account in the popular media to the research itself before making a judgment.  Most of the time, if there's a problem or a misrepresentation, it's the popular media that's at fault.

But not always.  So if you want to repel mosquitoes, you might want to do your own experiments.  There must be a better way than subjecting yourself and everyone around you to dubstep.

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This week's Skeptophilia book recommendation combines science with biography and high drama.  It's the story of the discovery of oxygen, through the work of the sometimes friends, sometimes bitter rivals Joseph Priestley and Antoine Lavoisier.   A World on Fire: A Heretic, an Aristocrat, and the Race to Discover Oxygen is a fascinating read, both for the science and for the very different personalities of the two men involved.  Priestley was determined, serious, and a bit of a recluse; Lavoisier a pampered nobleman who was as often making the rounds of the social upper-crust in 18th century Paris as he was in his laboratory.  But despite their differences, their contributions were both essential -- and each of them ended up running afoul of the conventional powers-that-be, with tragic results.

The story of how their combined efforts led to a complete overturning of our understanding of that most ubiquitous of substances -- air -- will keep you engaged until the very last page.

[Note:  If you purchase this book by clicking on the image/link below, part of the proceeds will go to support Skeptophilia!]