A geological champagne bottle

I've always found the idea of an unstable system fascinating, even before I knew the name to put on it.  As a kid I liked to do things like build towers of stones and see how high I could get them before they'd teeter and collapse, and got quite good at creating a multi-tiered house of cards.  (Can't do it any more -- I drink too much coffee to have the steady hands I did at age twelve.)  What I found interesting was that up to a point, such systems tend to self-stabilize; touch your tower of stones gently, and sometimes it'll jostle a bit then settle back into its original position.  But introduce too much energy into it, and it destabilizes fast.  After that, every bit of the collapse feeds more energy into the process, until all you have left is a pile of chaotic rubble.

This phenomenon of a tipping point -- the point where the system crosses the line between stable and unstable -- is a special case of a wider phenomenon called hysteresis, which is the dependence of a system's state on its history.  If something has started a trend in the past, sometimes it takes far less energy to keep it going than it did to get it started in the first place.  Think, for example, of popping the cork on a champagne bottle.  The amount of force you have to exert to push the cork up the bottle neck stays the same until... suddenly... it doesn't.  Once the frictional force between the cork and the neck is exceeded by the force exerted by the pressure in the bottle, the system changes state fast.

Bang.

Lots of systems act this way, but none quite as alarmingly powerful as a volcanic eruption.  Take, for example, what happened to Anak Krakatau, an island in the Sunda Strait in the Indonesian archipelago.  This island was the site of the stupendous 1883 eruption of Krakatau (more commonly, but less correctly, spelled Krakatoa), one of the largest in recorded history.  But volcanoes seldom stop at one eruption; the magma chamber feeding them doesn't just empty and go away.  The same processes that caused the first eruption eventually rebuild the volcano and generate subsequent outbursts.  Anak Krakatau ("Child of Krakatau" in Indonesian) emerged in 1927 from the giant caldera left by the eruption forty-four years earlier, and continued to grow and produce steam, ash bursts, and lava flows afterward.

An eruption of Anak Krakatau in 2008 [Image is in the Public Domain]

Then in 2018, the entire island collapsed.  I'm not overstating.  It lost two-thirds of its above-sea-level volume, and the summit dropped from 338 meters above sea level to 110.  This sudden cave-in generated a two-meter-high tsunami that killed over four hundred people and displaced forty thousand, mostly along the coastline of Sumatra and Java.  Geologists knew the potential of the island to generate another deadly eruption, and even that there was a potential for collapse, but no one saw it coming on the day it happened.  No warning, everything's quiet, then...

Bang.

The sudden collapse of Anak Krakatau was the subject of a paper this week in Earth and Planetary Science Letters which studied the lead-up to the event, looking at whether there were signs in the preceding months that might have tipped geologists off to what was going to occur.  And... scarily... there weren't.  Just like the cork in a champagne bottle giving you no warning when it's going to pop.  The authors write:

The lateral collapse of Anak Krakatau volcano, Indonesia, in December 2018 highlighted the potentially devastating impacts of volcanic edifice instability.  Nonetheless, the trigger for the Anak Krakatau collapse remains obscure.  The volcano had been erupting for the previous six months, and although failure was followed by intense explosive activity, it is the period immediately prior to collapse that is potentially key in providing identifiable, pre-collapse warning signals... [Our research] suggests that the collapse was a consequence of longer-term processes linked to edifice growth and instability, and that no indicative changes in the magmatic system could have signalled the potential for incipient failure.  Therefore, monitoring efforts may need to focus on integrating short- and long-term edifice growth and deformation patterns to identify increased susceptibility to lateral collapse.  The post-collapse eruptive pattern also suggests a magma pressurisation regime that is highly sensitive to surface-driven perturbations, which led to elevated magma fluxes after the collapse and rapid edifice regrowth.  Not only does rapid regrowth potentially obscure evidence of past collapses, but it also emphasises the finely balanced relationship between edifice loading and crustal magma storage.

This put me in mind of another geological phenomenon that results from a similar kind of champagne-cork effect; kimberlite eruptions, which I wrote about here last year, and which apparently have the same no-warning-then-boom behavior.  (These are the eruptions that produce diamonds -- and, once you read my post, you'll be glad to hear that they are thought to be a feature of Earth's distant past, and very unlikely to happen now.)

It's easy for us to look around and think everything we see -- not only the geology, but the climate, the global ecosystem, society itself -- is stable, and any perturbations will set up a feedback that will return everything to "normal."  The problem is, for a lot of systems, there is no "normal."  They're stable up to a point -- but if pushed beyond that point, unravel fast.  Some of these phenomena, like the caldera collapse that struck Anak Krakatau four years ago, are powerful and unpredictable, and other than evacuating people, there wouldn't have been anything we could have done to prevent it even if we had known.  But we'd damn well better not close our eyes to the analogy between this event and the bigger picture.  It's easy and convenient to believe that "everything will be fine because it's always been fine," but that kind of thinking gives people license to keep poking at things, heedlessly pushing on the superstructure and acting like it has infinite resilience.

Then, without any warning, where you had an orderly stone tower, all you have left is a pile of rocks, dust, and debris.

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Since reading the classic book by Desmond Morris, The Naked Ape, when I was a freshman in college, I've been fascinated by the idea of looking at human behavior as if we were just another animal -- anthropology, as it were, through the eyes of an alien species.  When you do that, a lot of our sense of specialness and separateness simply evaporates.

The latest in this effort to analyze our behavior from an outside perspective is Pascal Boyer's Human Cultures Through the Scientific Lens: Essays in Evolutionary Cognitive Anthropology.  Why do we engage in rituals?  Why is religion nearly universal to all human cultures -- as is sports?  Where did the concept of a taboo come from, and why is it so often attached to something that -- if you think about it -- is just plain weird?

Boyer's essays challenge us to consider ourselves dispassionately, and really think about what we do.  It's a provocative, fascinating, controversial, and challenging book, and if you're curious about the phenomenon of culture, you should put it on your reading list.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Prelude to a detonation

Even though in general I don't think synchronicity Means Anything, there's no doubt that it can be pretty peculiar.

For example, it seems like in the last few days the universe has tried to get me to think about volcanoes.  First, Scientific American recently featured in their "New Books" column Robin George Andrews's Super Volcanoes, and given my fascination with volcanoes in general I had to get it (and it impressed me enough that it's this week's book-of-the-week).  Andrews's book goes a long way toward dispelling a lot of the hype around places like Yellowstone (no, it's not on the verge of an eruption), and has a lot of cool interviews with volcanologists, much in the style of the wonderful essayist John McPhee.  Only a couple of days after I started reading it, a friend sent me a link to the Naked Science YouTube video "Supervolcanoes," which seemed to be the anti-Andrews; if I can sum it up, it would be "WE'RE ALL FUCKED RUN FOR YOUR LIFE."  It isn't terrible, and does include some actual science, but the most striking thing about it is a CGI rendition of Yellowstone blowing sky-high which they use over and over and over and over in the fifty-minute-long video, as if they'd paid somebody a hefty sum to do the rendering, and by god, they were gonna get their money's worth out of it.

Then, just yesterday, a (different) friend sent me a link to a paper in Proceedings of the National Academy of Sciences that kind of splits the difference between Naked Science's screaming alarmism and Andrews's breeziness; it looks at the scarily huge Mount Toba volcano in Indonesia, and comes to the unsettling conclusions that (1) it definitely will erupt again, and (2) we probably won't have much warning when it does.

The last significant eruption of Toba was about 74,000 years ago, and was a VEI8 -- the highest ranking on the Volcanic Explosivity Index -- releasing an estimated three thousand cubic kilometers of ash and lava, and causing a worldwide (if temporary) drop in average temperature by about three degrees Celsius.  (For comparison, this is over seven hundred times the volume ejected by the May 1980 eruption of Mount St. Helens.)  The eruption blew the entire top of the mountain clean off, and the evacuation of the magma chamber beneath it caused the caldera to collapse.  It filled with water, and is now a beautiful -- and seemingly peaceful -- crater lake, Lake Toba.

[Image licensed under the Creative Commons Visions of Domino, Indonesia - Lake Toba (26224127503), CC BY 2.0]

The operative word here is "seemingly."  The processes that caused the original eruption, mostly the subduction of the Indian and Australian Tectonic Plates beneath the Sunda Plate, continue to cause massive earthquakes including the colossal (9.2 on the Richter Scale) Sumatra-Andaman Earthquake of December 2004, which killed over 225,000 people.  In the case of Toba, the magma chamber has been steadily refilling, and now contains an estimated 50,000 cubic kilometers of magma -- four times the volume of Lake Superior.  This refilling has pushed the entire caldera upward, lifting Samosir Island and the Uluan Peninsula an estimated 450 meters.

It's hard to talk about this without lapsing into superlatives.  The scariest thing about it, though, is that the recent study indicates that such volcanoes can seem quiescent until -- well, until they aren't any more.  "[W]ith few super-eruptions in the last two million years, it is not possible for us to obtain statistically significant values for the frequency of these catastrophic events at a global scale," said study co-author Ping-Ping Liu of Peking University, in a press release from the Université de Genève.  "Our study also shows that no extreme events occur before a super-eruption.  This suggests that signs of an impending super-eruption, such as a significant increase in earthquakes or rapid ground uplift, might not be as obvious as pictured in disaster movies by the film industry.  At Toba volcano, everything is happening silently underground."

The reassuring part is "not as obvious" doesn't mean "without any warning;" the entire Indonesian archipelago is an area of intense study by volcanologists and seismologists, and it's likely there'd be enough anomalous activity to give us at least a hint that an eruption was impending.  Whether we'd do much about it in the form of evacuations is another matter.  Sumatra (where the volcano is located) and the nearby island of Bali are densely populated, and the idea of getting all those people out (to where?) makes the phrase "mammoth undertaking" a significant understatement.  And for those of you who like certainty, the current study doesn't give us any clear idea of exactly when the next big eruption will occur, just that (1) it's inevitable, (2) when it does, it'll be bad, (3) the filling of the magma chamber is still happening, and (4) there are signs that the volcanic activity at Toba and the surrounding regions is speeding up.

"[There's been a] progressive increase of the temperature of the continental crust in which Toba’s magma reservoir is assembled," Liu said.  "The input of magma has gradually heated the surrounding continental crust, which makes the magma cool slower.  This is a ‘vicious circle’ of eruptions: the more the magma heats the crust, the slower the magma cools and the faster the rate of magma accumulation becomes.  The result is that super-eruptions can become more frequent in time."

So there's your cheerful news of the day.  As far as the synchronicity aspect of this, I'm not gonna make much of it.  The fact that two different friends know enough of my obsession with volcanoes and earthquakes to send me the link to the YouTube video and paper is hardly to be wondered at.  As far as the book review, it's no wonder I noticed it given that the tile of the book is Super Volcanoes.  I don't think this is some kind of cosmic warning that we're about to get blown to smithereens.

So if you were looking for an excuse to stay home from work this week, you'll probably have to come up with a different one.

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If Monday's post, about the apparent unpredictability of the eruption of the Earth's volcanoes, freaked you out, you should read Robin George Andrews's wonderful new book Super Volcanoes: What They Reveal About the Earth and the Worlds Beyond.

Andrews, a science journalist and trained volcanologist, went all over the world interviewing researchers on the cutting edge of the science of volcanoes -- including those that occur not only here on Earth, but on the Moon, Mars, Venus, and elsewhere.  The book is fascinating enough just from the human aspect of the personalities involved in doing primary research, but looks at a topic it's hard to imagine anyone not being curious about; the restless nature of geology that has generated such catastrophic events as the Yellowstone Supereruptions.

Andrews does a great job not only demystifying what's going on inside volcanoes and faults, but informing us how little we know (especially in the sections on the Moon and Mars, which have extinct volcanoes scientists have yet to completely explain).  Along the way we get the message, "Will all you people just calm down a little?", particularly aimed at the purveyors of hype who have for years made wild claims about the likelihood of an eruption at Yellowstone occurring soon (turns out it's very low) and the chances of a supereruption somewhere causing massive climate change and wiping out humanity (not coincidentally, also very low).

Volcanoes, Andrews says, are awesome, powerful, and fascinating, but if you have a modicum of good sense, nothing to fret about.  And his book is a brilliant look at the natural process that created a great deal of the geology of the Earth and our neighbor planets -- plate tectonics.  If you are interested in geology or just like a wonderful and engrossing book, you should put Super Volcanoes on your to-read list.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

The strangest flower on Earth

Anyone know what the world's largest flower is?

Chances are, some of you know that honor goes to the bizarre Indonesian species Rafflesia arnoldi, which produces flowers that can get to be 120 centimeters across.  Not only are they huge, they are (1) really weird-looking, and (2) smell like rotting meat in order to attract the flies that pollinate them.

Rafflesia arnoldi  [Image licensed under the Creative Commons ma_suska, Rafflesia sumatra, CC BY 2.0]

The first time I saw a photograph of this plant, I was immediately reminded of the Lost in Space episode "Attack of the Monster Plants," which was a real favorite of mine when I was a kid, not only because who wouldn't love a show about monster plants, but because Judy Robinson was in peril during this episode and to say I was madly in love with Judy Robinson is rather an understatement.

Be that as it may, the reality of Rafflesia is almost as weird as Judy's spaceship-fuel-eating alien plants.  The flower is enormous but the rest of the plant is minuscule, only a thin ribbon of translucent tissue that punctures the roots of vines of the rainforest genus Tetrastigma, getting all its nutrients from the host plant rather than from photosynthesis.  The only time any part of the plant is above ground is when it's flowering.  After that, the flowers wither, the fruits containing thousands of nearly microscopic seeds that are thought to be dispersed when tree shrews eat the fruit and poop out the seeds somewhere else.  But the plant's rarity, and the fact that during most of its life cycle you could walk right by it (or more likely, over it) without knowing, not that much is known for sure.

Another thing that's surprising about the family (Rafflesiaceae) is that its nearest relatives are euphorbias -- which include a huge range of plants united by having tiny, insignificant flowers and milky toxic sap and looking absolutely nothing like Rafflesia.  A number of euphorbs look superficially like cacti, with reduced or absent leaves and sharp spines, but the milky sap and inconspicuous flowers would clue you in to the fact that the similarities are due to convergent evolution.  The most familiar euphorb is the poinsettia -- the bright red, pink, or cream-colored parts are not actually petals but modified leaves.  (The flowers themselves are the little b-b sized bits at the center.)

So what this shows is that to figure out evolutionary relationships, you can't rely on what things look like.  As odd as it is, the spiky candelabra spurge (Euphorbia ingens) is a cousin of the bizarre Rafflesia.

If all that isn't weird enough, consider a study that just came out a couple of weeks ago in Current Biology that looked at another member of Rafflesiaceae, the genus Sapria.  (They're very similar to Rafflesia, differing only in a few not-very-significant botanical details.)  This study did an extensive analysis of the genetics of Sapria, and found something bizarre; during its descent from its euphorbia-like ancestors, Sapria (and presumably the rest of the family Rafflesiaceae) has not only lost just about all of its physical structure, but half of its genome -- including the entire array of genes that produce chloroplasts.  Stranger still, in the process it has picked up genetic material from its host, something called horizontal transfer.

So this puts paid to the incorrect notion a lot of people have that evolution always makes things bigger, stronger, smarter, and more complex.  Evolution is the law of whatever works at the time, and if what works is to jettison half the DNA along with chloroplasts, leaves, and true roots, that can happen.  And if you think about it, it makes sense; if you're a plant that spends nearly its entire life underground, why waste resources making structures like leaves and chloroplasts, not to mention all the proteins and pigments that go into making them work?  The oddest thing about the genetics, though, is that a lot of the genes that Sapria has picked up from its hosts don't seem to do anything; they appear to be "non-coding regions" of DNA that don't have any obvious function.  "There's something weird and different going on in this species," said Tim Sackton of Harvard University, who co-authored the paper, in an interview with Science News.  "Maybe these organisms that stretch the boundaries of existence tell us something about how far the rules can be bent before they can be broken."

Rafflesia and its relatives are certainly some of the strangest members of the plant kingdom, so much so that you have to wonder what other peculiarities are going to be uncovered by further analysis.  I just hope we don't find out that it eats rocket fuel and creates evil duplicates of people, because Judy Robinson barely escaped with her life, and that is not okay.

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Science writer Elizabeth Kolbert established her reputation as a cutting-edge observer of the human global impact in her wonderful book The Sixth Extinction (which was a Skeptophilia Book of the Week a while back).  This week's book recommendation is her latest, which looks forward to where humanity might be going.

Under a White Sky: The Nature of the Future is an analysis of what Kolbert calls "our ten-thousand-year-long exercise in defying nature," something that immediately made me think of another book I've recommended -- the amazing The Control of Nature by John McPhee, the message of which was generally "when humans pit themselves against nature, nature always wins."  Kolbert takes a more nuanced view, and considers some of the efforts scientists are making to reverse the damage we've done, from conservation of severely endangered species to dealing with anthropogenic climate change.

It's a book that's always engaging and occasionally alarming, but overall, deeply optimistic about humanity's potential for making good choices.  Whether we turn that potential into reality is largely a function of educating ourselves regarding the precarious position into which we've placed ourselves -- and Kolbert's latest book is an excellent place to start.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

A lens into the past

I have the unfortunate tendency to get fascinated by things that are impossible to research.

I was asked not too long ago about when and where -- if time travel into the past were possible -- I'd like to visit.  My immediate answer was Britain during the "Dark Ages," the period between the withdrawal of Roman forces in the 5th century C.E. and the Anglo-Saxon conquest in the 7th century.

My friend asked why I picked that time and place.  What was so interesting about it?

"I don't know if there's anything interesting about it," I responded.  "It's because no one really knows what happened during that time span.  There are almost no written records -- just about everything we know is from writings done three or four hundred years later.  It's the lack of information that fascinates me."

Fortunately, it's not always necessary to have written records to find out about a place's history.  That's why we have archaeology.  We can obtain a remarkably clear picture about a long-gone society simply from the debris it leaves behind.

There were three wonderful examples of this just in the last two weeks.

In the first, researchers in the Nile Delta found a skeleton and other artifacts in a place called Tell Timai (known as Thmouis in Ptolemaic times).  The skeleton was dated to about 180 B.C.E.  It showed numerous signs of trauma -- both healed and unhealed injuries to the bone, and evidence that its owner hadn't been buried so much as thrown on the ground and covered with a thin layer of dirt and sand.

Why the timing of this is interesting is that the man's death was during the same period as a revolt against Pharaoh Ptolemy V by native Egyptian rebels (the Ptolemies themselves were Greeks, and were widely regarded by their native subjects as usurpers).  Ptolemy successfully squashed the rebellion, an event that is recorded on one of the most famous written documents of all -- the Rosetta Stone.

The skeleton of the unfortunate Tell Timai man not only shows injuries typically suffered on the battlefield, but was surrounded by evidence of battle -- arrowheads and scorched "ballista balls" (a baseball-sized projectile fired from Greek and Roman catapults).  Also present were coins dating to no earlier than 205 B.C.E.  This is precisely the timing of the Thmouis Revolt -- the Rosetta Stone says it went on in a sporadic fashion starting around 206 B.C.E. and ending with the decisive battle twenty years later.

So it appears that the Tell Timai skeleton is a war casualty from a battle recorded on one of the world's most celebrated written records.


Archaeological findings can go back a hell of a lot longer ago than 2,200 years, however.  Another discovery that was reported last week is from Indonesia, and gives us a lens into a time when (as far as we know) writing had yet to be invented.  A cave painting on the island of Sulawesi, dated to 43,900 years ago, is a hunting scene -- by itself not that uncommon -- but the hunters depicted are what archaeologists call therianthropes, which are mythical human/animal hybrids.

A detail of the Sulawesi cave painting

What's exciting about this is that it shows the artist wasn't just depicting realism, (s)he was telling a story.  We've apparently been storytellers for a very long time, something that (as a novelist) makes me very happy.

"The human-animal figures in the Sulawesi hunting scene are quite small relative to the pig and anoa [a small native species of buffalo] images," said Nicholas Conard, archaeologist at the University of Tübingen.  "That may be because ancient artists depicted these therianthropes as flying.  In the stories and personal accounts of people from modern foraging groups, movements through spirit worlds are often via flight rather than walking or running."

So just like we do today, our very distant ancestors enjoyed telling fanciful stories about strange creatures -- and some of those stories made their way into art.


People who know me are aware of another of my strange obsessions, and that's with body art.  I have three tattoos, one of which is a full sleeve that extends onto my chest -- it's not like I exactly keep it secret, or anything.  So after finding the previous article, about our history as storytellers, it made me happy to jump to the next, which shows that we've also been decorating our own bodies for a long, long time.

Archaeologist Anne Austin, of the University of Missouri, was working with three thousand year old mummies from Deir el-Medina in Egypt, and upon analyzing x-rays found clear evidence of tattoos.  One woman, presumed to be a religious leader or practitioner of magic, had no fewer than thirty tattoos, including an intricate pattern of crosses on both of her arms.  Another had symmetrically-placed images of the Eye of Horus, and a third a seated baboon -- symbolizing knowledge and wisdom -- on the side of her neck.

"Only tattooed females have been identified at Deir el-Medina," Austin said.  "Discoveries there challenge an old idea that tattoos on women connoted fertility or sexuality in ancient Egypt.  Deir el-Medina tattoos appear to be more closely associated with women’s roles as healers or priestesses."

It's amazing what we can learn about human history without written records (or, in the case of the Tell Timai skeleton, how we can supplement what written records we have).  Everything the archaeologists uncover makes the picture clearer.  As my dear friend, the novelist Cly Boehs (author of the brilliant Back Then and The Most Intangible Thing) puts it, "We are made of the stories we tell."

And sometimes those stories resonate down through the ages, giving us a glimpse of societies that have been gone for thousands of years.

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This week's Skeptophilia book recommendation is pure fun, and a perfect holiday gift for anyone you know who (1) is a science buff, and (2) has a sense of humor.  What If?, by Randall Munroe (creator of the brilliant comic strip xkcd) gives scientifically-sound answers to some very interesting hypothetical questions.  What if everyone aimed a laser pointer simultaneously at the same spot on the Moon?  Could you make a jetpack using a bunch of downward-pointing machine guns?  What would happen if everyone on the Earth jumped simultaneously?

Munroe's answers make for fascinating, and often hilarious, reading.  His scientific acumen, which shines through in xkcd, is on full display here, as is his sharp-edged and absurd sense of humor.  It's great reading for anyone who has sat up at night wondering... "what if?"

[Note:  if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

When the volcano blows

Nobel Prize-winning physicist Richard Feynman once said, "I would rather have questions that cannot be answered than answers that cannot be questioned."

The strength of science is in its ability to self-correct, but this does engender a problem; it may well be that some of the questions we're asking will never be satisfactorily answered.  There are sometimes when we must admit ignorance, and hold our determination to have everything figured out in abeyance -- possibly indefinitely.

That may be the situation we're in with regards to an interesting question surrounding the largest volcanic eruption in modern times, the eruption of Toba in the Indonesian archipelago.  This eruption dwarfed Mount Saint Helens, the 1883 eruption of Krakatoa, and even the catastrophic eruption of Tambora (also in Indonesia) in 1815, that threw so much in the way of debris up into the atmosphere that it caused the "Year Without a Summer," in which Quebec City got a foot of snow -- in mid-July.

The Toba eruption, 74,000 years ago, was bigger than all of the above; by some estimates, it threw a hundred times more in the way of pulverized rock into the air than Tambora did.  It is certain that it caused not only localized devastation, but worldwide climate change.  And the conventional wisdom is that it nearly wiped out the human species -- that we were driven into a genetic bottleneck, in which only a few survivors became the ancestors of everyone currently alive today.

The Toba caldera [image courtesy of the Wikimedia Commons]

Michael Rampino and Stanley Ambrose, of New York University, were amongst the first proponents of the Toba bottleneck theory.  In their paper "Volcanic Winter in the Garden of Eden: The Toba Supereruption and the Late Pleistocene Human Population Crash," published in 2000 in the Papers of the Geological Society of America, they write:

Genetic studies indicate that sometime prior to ca. 60,000 yr ago humans suffered a severe population bottleneck (possibly only 3,000-10,000 individuals), followed eventually by rapid population increase, technological innovations, and migrations.  The climatic effects of the paroxysmal Toba eruption could have caused the bottleneck, and the event might have been a catalyst for the technological innovations and migrations that followed.  The present results as to the predicted environmental and ecological effects of the eruption lend support to a possible connection between the Toba event and the human population bottleneck, and suggest that similar bottlenecks among other organisms might be expected at about the same time. 

However, it appears that the question is far from settled.  A paper by Eugene Smith et al. that came out last week in Nature, "Humans Thrived in South Africa Through the Toba Eruption about 74,000 Years Ago," completely counters the conventional wisdom -- and suggests that if the bottleneck did occur, it may not have been the fault of the volcano:

Approximately 74 thousand years ago (ka), the Toba caldera erupted in Sumatra.  Since the magnitude of this eruption was first established, its effects on climate, environment and humans have been debated.  Here we describe the discovery of microscopic glass shards characteristic of the Youngest Toba Tuff—ashfall from the Toba eruption—in two archaeological sites on the south coast of South Africa, a region in which there is evidence for early human behavioural complexity.  An independently derived dating model supports a date of approximately 74 ka for the sediments containing the Youngest Toba Tuff glass shards.  By defining the input of shards at both sites, which are located nine kilometres apart, we are able to establish a close temporal correlation between them.  Our high-resolution excavation and sampling technique enable exact comparisons between the input of Youngest Toba Tuff glass shards and the evidence for human occupation.  Humans in this region thrived through the Toba event and the ensuing full glacial conditions, perhaps as a combined result of the uniquely rich resource base of the region and fully evolved modern human adaptation.

The reason I bring this up -- besides the fact that I'm interested in human population genetics, and it's cool -- is that this may be a question that we simply don't have the data to answer.  It's possible that the "thriving" population that Smith et al. found was a localized group of lucky people, and elsewhere, humanity got clobbered.  On the other hand, it could be that the Rampino and Ambrose paper was simply wrong -- that the population genetics studies, which are not without their a priori assumptions, overestimated the extent of the Toba bottleneck (or the whatever-caused-it bottleneck).

But -- and this is the most critical point -- you keep looking.  If there's no definitive solution, you are forced to admit it, but the research doesn't stop there.  Ignorance is the beginning, not the end, of the scientific process.

So we may never know exactly how close humanity came to extinction 74,000 years ago.  The important thing is that we've asked the question -- and that science gives us a means to evaluate the evidence, and determine if a particular answer is supported.  And what we learn along the way will open up further avenues for exploration, enough to keep the scientific world occupied for a long, long time.

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Redemption, retribution, and justice

Yesterday, on an island in Indonesia, at midnight local time and 1 PM Eastern Standard Time, eight men were brought out into a wooded grove one at a time and were executed by a firing squad.  Each one was given the choice of whether to sit or stand, and to have a hood, a blindfold, or nothing at all.  All eight chose nothing, and to look the members of the firing squad in the eye as they died.  Three of the eight executioners had live ammo in their guns; the other five had blanks.  No one knew which guns were which.

When the prisoner was ready, the firing squad took aim at the man's heart.  The command to fire was given, and seconds later, the condemned man was dead.

The crime the eight committed was possession of drugs with the intent to distribute.  Two were members of the infamous "Bali 9" drug trafficking ring.  Each had been caught entering the country with heroin or cocaine.  Four of the men were from Nigeria, two from Australia, one from Brazil, and one from Indonesia.

[image courtesy of the Wikimedia Commons]

Most, if not all, of the men had experienced significant personal changes during their four-year stay in prison, while their cases dragged through appeal after appeal.  One, Australian Myuran Sukumaran, spent his time painting; his final paintings were of a heart, and a haunting self-portrait with a black hole in the center of the chest.  The other Australian, Andrew Chan, and one of the Nigerians, Okwudili Ayotanze, became well known for offering solace and counsel to their fellow prisoners.  All appeared completely repentant for what they had done.

Further complicating matters, the Brazilian, Rodrigo Gularte, was a diagnosed schizophrenic, who thought animals could talk back to him and believed that electromagnetic waves were controlling his behavior.

The whole thing brings up a lot of questions about why the judicial system works as it does.  Why do we imprison, and in some cases execute, people who have broken the law?  It seems to me that there are three answers to this question -- and they lead to different answers regarding how we should treat criminal cases.

The first is that justice is retributive.  Some of the oldest known codes of law, such as the Code of Hammurabi, are retributive in nature.  If you cause someone to lose a hand, you should lose your hand.  The basic logic is payback; "you deserved everything you got."

The second is to protect society.  By this standard, two people who commit the same crime should be treated differently depending on how much of a subsequent threat each one represents.  And this is considered in sentencing, at least in the United States; someone who is likely to commit further crimes is often given a harsher sentence.

The third is to set an example.  "See what happened?" this standard says.  "You don't want this to happen to you."  It was for this reason that floggings and executions used to be conducted in public, often in the middle of the town square.  Such events were often widely attended, as peculiar as that may seem to modern sensibilities.  The last public hanging in the United States, of rapist/murderer Rainey Bethea, was attended by 20,000, and was such a media circus that the decision was made to conduct executions behind closed doors from then on.

All of which demands that we consider how to deal with cases of serious crimes.  What the eight men  did was terrible; heroin and cocaine are horrible chemicals that destroy lives.  From the standpoint of retribution, the sentence was fair.  And the publicity surrounding the case certainly should act as a deterrent; no one could fail to be moved by the photographs of the hysterical family members of the executed men, and it's hard to imagine anyone considering bringing drugs into Indonesia not being given pause.

But there are still questions.  If the idea of justice is to safeguard society, the focus should be on rehabilitation, not retribution.  From what I've read, certainly Chan and Sukumaran were rehabilitated, and not only would have been unlikely to do anything of the sort again, but might well have been powerful spokesmen against the illegal drug trade.  Apparently a change of heart is what saved Malaysian drug trafficker Yong Vui Kong from being hanged in Singapore; his sentence was changed to life in prison and fifteen strokes of the cane because he had "seen the error of his ways and had repented."

As far as rehabilitation goes, however, you have to wonder how effective that usually is even in non-capital cases.  Recidivism rates are sky-high.  A study by the National Institute of Justice of over 404,000 prisoners in the United States found that 76.6% of them were re-arrested within five years, over half of those arrests occurring within the first year after release.

Add to this the fact that the execution of drug traffickers has barely put a dent in the Southeast Asian drug trade; the region is the second biggest producer of heroin in the world (after Afghanistan).  And the people most often caught are the couriers, who are usually young, poor, and desperate.  The kingpins, the ones who are controlling the operations and getting rich from the profits, are seldom ever brought to justice.

None of that mattered.  Indonesian President Joko Widodo said from the beginning that there would be no clemency granted.  And there wasn't.

I'm not sure why this case resonated so strongly with me.  I was fairly certain what the outcome would be, so it wasn't over any particular curiosity over what would happen.  I think it may have been the personal angle -- I read articles containing interviews with Chan's girlfriend, whom he married a few months ago while he was already in prison.  I saw galleries of Sukumaran's paintings.  I read the statements by the lawyers of the eight prisoners and the pleas by leaders of their home countries to spare them.  I thought about the ethics of executing someone like Rodrigo Gularte, who had a serious mental illness.

And yesterday, while I was teaching my Critical Thinking class, eight men halfway around the world were shot through the heart.  In the final analysis, I have no real idea whether this was just or unjust, ethical or unethical.  Nor can I decide whether President Widodo should have considered any other factors in his decision to allow the executions to proceed.

All I can say is that I'm glad that I will never be in a position to make such a judgment.

Weekend wrap-up

It's been a busy week,  here at Worldwide Wacko Watch.  I and my investigative team (made up of my two highly-trained dogs, Doolin and Grendel) have dug up some wonderful stories that will hopefully not make you lose complete faith in the intelligence of the human race.

First, from Indonesia, we have word that there is a law being drafted that will make black magic illegal.  Not only will casting spells and harming someone be punishable by jail time, even claiming to be able to do so will be considered a criminal offense.  Khatibul Umam Wiranu, an MP from the Democrat Party, believes that these measures are necessary to protect the populace from evil magicians.  But, he cautions, any charges of witchcraft filed should be "based on fact finding, not [just] on someone's statement."

Well, that should at least make it less likely anyone's going to be arrested.

Other proposed changes to the penal code include increasing jail time for such crimes as having sex with someone you're not married to.

The best part?  Proponents of the new laws are calling this a push to "modernize" Indonesia's out-of-date criminal code, which was last revised in 1918.  Because worrying about who's getting laid by whom, and claiming that the creepy-looking old lady down the street is a witch, is so 21st century.


Go a few hundred miles north into China, and we find our second story, which is a "beauty treatment" called "huǒ liáo" that involves setting your face on fire.  [Source]

I thought that mooshing charcoal paste and nightingale poop extract on your skin was the dumbest beauty treatment I'd ever heard, but this one takes the prize.  Huǒ liáo consists of soaking a towel in alcohol and a "secret elixir," and the practitioner putting it on your face or other "problem area" and then setting it ablaze.  The practitioner is supposed to quickly smother the fire with another towel.  Don't believe me?  Here's a picture of someone having the treatment:

Nope, I see nothing at all that could possibly go wrong with that.

When asked about the treatment, a doctor who specializes in "natural cures," Dr. Jacob Teitelbaum, said, "While alcohol will help carry whatever is in the elixir into the body, it's not really necessary to light it on fire.  However, one explanation is that extreme heat triggers an adrenaline response which can shift your body's chemistry, improving some symptoms like indigestion and slow metabolism."

You know, if I want an adrenaline rush, I'll just go ziplining or ride a roller coaster.  Anyone who needs to set his/her face on fire in order to get an "adrenaline response" has other problems besides dull skin.


Next, we have a story in from Spain that someone has discovered a carving in some stonework in a cathedral that dates from the 12th century that depicts...

... an astronaut.

The carving, which apparently shows a guy in an Apollo-program-style space suit, is on the Cathedral of Salamanca.  Want to take a look?  Here you go:

 

 Of course, this has given multiple orgasms to the whole "ancient astronauts" crew, the ones who think that Chariots of the Gods is Holy Writ, who think the pyramids were built by aliens, and so on.  The only problem is, the cathedral was renovated in 1992, and this stonework was clearly added then by an artist with a sense of humor.  In fact, Snopes.com has a page on this claim, and they even found an article in a Portuguese newspaper that described the figure:

The renovation of the Cathedral of Salamanca in 1992 integrated modern and contemporary motifs, including a carved figure of an astronaut.  The use of this motif was in the tradition of cathedral builders and restorers including contemporary motifs among older ones as a way of signing their works.  The person responsible for the restoration, Jeronimo Garcia, chose an astronaut as the symbol of the twentieth century.

Well, that sounds pretty unequivocal, doesn't it?  Unfortunately, this hasn't convinced anyone except the people who were already skeptical, and all it's done is hooked up the Ancient Astronauts crew with the Conspiracy Theories crew, and now we have claims that the Spanish (and/or Portuguese) governments are covering up the evidence of ancient alien invasion, for god alone knows what reason.


In any case, this brings us to our last story, which is about a petition that is currently out there to save planet Earth from an extraterrestrial attack.  How, exactly, signing a petition is going to help, I don't know.  Maybe when the aliens get here, and are on the verge of blowing us to smithereens with their laser cannons, we can shout, "No!  You can't do that!  WE HAVE A PETITION!"  Maybe the idea is that if enough people sign it, governments will for god's sake do something, such as to deploy a protective shield around the Earth in the fashion of the historical documentary Men in Black III.  I dunno.

In any case, the petition has currently garnered a whole fourteen signatures.  They're shooting for 100,000.  You can sign if you want to.  Me, I probably won't.  My general feeling is that any species that modernizes laws by outlawing witchcraft and premarital sex, and considers setting your face on fire a beauty treatment, deserves everything it gets.