Different strokes

So once again, a member of the extreme evangelical fringe of Christianity has launched a campaign against our taking pleasure in something which we are biologically hard-wired to find pleasant.

Yesterday a loyal reader of Skeptophilia alerted me to the fact that Mack Major, a Christian writer from Philadelphia, has written a book called Sex Magic: Flirting With the Demonic in which he claims we shouldn't masturbate because masturbation can "summon a sex demon."

Here's a direct quote, in case you think I am making this up:

There are such things are sex demons.  And the danger in masturbating is that one could inadvertently summon a sex demon to attach itself to you through the act of masturbating.  And once that demon attaches, it is difficult to get it to leave.  It will drive you to masturbate, even when you don’t want to.  You’ll be hit with urges to play with yourself so powerful that only an orgasm will allow you some temporary relief.

Notwithstanding the fact that if this were true, the millions of teenage boys worldwide would be keeping the sex demons busy 24/7, Major seems convinced that by engaging in what my dad referred to as "shaking hands with the unemployed" you are writing yourself a one-way express ticket to hell.

Presumably with the other hand.

Major is also vehemently against any use of gadgets for increasing your enjoyment, even if those are used with a partner.  Erotic toys provide yet another means of ingress for those pesky sex demons:

Many of you who are reading this have sex toys in your possession right now.  And whether you want to accept it as fact or not: those sex toys are an open portal between the demonic realm and your own life.  As long as you have those sex toys in your home, you have a doorway that can allow demons to not only access your life at will, but also to torment you, hinder and destroy certain parts of your life as it relates to sex and your relationships.

Which highlights yet again my disagreement with the devoutly religious over the definition of the word "fact."

Besides the scary sex demons, it turns out that pleasuring yourself can also cause volcanic eruptions, and he's not using that in its justifiable metaphorical sense.  He means literal volcanic eruptions.  He tells us all about the pornographic scenes found on the walls of Pompeii, many of which involved the god Priapus, who was depicted as a naked dude with an enormous hard-on.  And he links that directly to what happened:

He [Priapus] was really popular in the ancient city of Pompeii…  The walls of many of the homes and palaces were painted with detailed frescos of very graphic pornographic sexual scenes…  Keep in mind that Pompeii was suddenly destroyed and thousands of lives were wiped out in an instant.

So yeah, that was a really unhappy ending.  Be that as it may, it's hard to see the pyroclastic flow from Vesuvius as having anything to do with jacking off, or there'd be a major explosion underneath every adult theater in the United States every single night.  And the headquarters of PornHub would right now simply be a giant smoking crater.

My main reaction to all this is that I feel cheated.  I have never once been visited by a sex demon.  I mean, what the hell, sex demons?  What's the problem, here?  Am I not good enough?  I'm giving it my all, over here.  It's enough to make a guy feel a little inadequate.

The exasperating thing about all this is that masturbation is 100% normal, nearly everyone does it, it relieves stress, helps you sleep, and (for men) decreases the risk of prostate cancer.  What we have here is simply another way for the extremely religious to make everyone feel guilty, uptight, and anxious over something entirely harmless, and to maintain their control by convincing their followers that they're hellbound if they don't follow the leader's advice to the letter.

Major ends with one last cautionary note:

When we imagine having sex with another via masturbation, we are actually summoning the power of the spirit realm to manifest the thing we are imagining.

Don't I wish.  Manifest away, spirit realm.  Hey, I'm bi, so there's twice the manifestations I'd be perfectly happy with.  Either Jenna Coleman or Liam Hemsworth, for example, would do just fine.

So anyway.  My advice is: in the privacy of your own home, do what comes naturally, enjoy it, and find something else to fret about.  I'm guessing that even if there is a supreme deity, he/she/it has much better things to do in Universe Management than keeping track of what you do in your "Alone Time."

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Modern-day Cassandras

When people think of environmental degradation, usually what comes to mind are urban areas, agricultural land either grazed bare by cattle or sheep or devoted to monoculture farming, and obviously damaged sites like mines, oilfields, and landfills.  It's a little alarming when studies are done that show that an entire country is an example of a severely degraded environment.

Especially when the country is as big as Australia.

[Image licensed under the Creative Commons Diliff, Koala climbing tree, CC BY-SA 3.0]

My guess is that Australia wouldn't be the first place you'd think of when it comes to ecological damage.  But a two-thousand-page state of the environment report, commissioned by the Australian government, resulted in an overall assessment that the condition of the country's ecosystems is "shocking."  Amongst the findings:

• Nineteen of Australia's ecosystem are "on the verge of collapse."
• Non-native plant species now outnumber native ones.
• More species have gone extinct in Australia in the last two hundred years than on any other continent.  (Not country; continent.)
• Two hundred species endemic to Australia -- found nowhere else in the world -- have experienced upgraded threat status in the last five years.
• In the past ten years, there has been a record number of droughts, wildfires, record-breaking floods, and typhoons.
• There have been six major coral-bleaching events on the Great Barrier Reef, the largest coral reef in the world.

In a dramatic example of how environmental effects don't stop at national borders, a large contributor to the problem has been climate change -- even though Australia's government has committed to cutting carbon emissions by 43% by the year 2030.  Which is lovely, but when there are countries like the United States still thumbing their noses at decreasing fossil fuel use, it's not going to make much difference.

Not that the Australians themselves have done everything right, mind you.  Many of the exotic species -- most notoriously, the European rabbit -- were brought in deliberately.  Previous governments have been much less eco-friendly than the current one, usually citing budget issues as an excuse not to do anything.

It reminds me of a discussion I had with one of my environmental science students years ago.  The question I threw out to the class was, "What would it take for governments to take action on environmental issues, specifically carbon emissions and climate change?"  Her answer was, "Things will have to get a great deal worse.  Bad enough that ordinary people have their lives drastically changed.  When the food starts running out, when the heat starts killing not just poor people in third world countries but middle-class folks right here in the United States.  I hate to put it this way, but until it's bad enough that people living right in our neighborhoods are dying because of it, we'll just keep on doing what we've always done and pretending everything's okay."

I think she's spot-on.  The problem is, once it gets to that point, it's too late to do anything to halt it.  As the Australians have found out, as the Americans and Western Europeans are finding out, once entire countries are sweltering in a pressure cooker, there's not much you can do other than try to survive it -- and accept that some won't.

Of course, developing countries and the third world has known that for decades.  Right now, Pakistan, India, and large parts of central and northern Africa are experiencing record high temperatures as well.  Unlike the United States and Western Europe, though, this is nothing new.  It seems like every year they have a new record-setting heat wave, people die, and it barely is a blip on the radar in the industrialized world.

Yet another reason why we think we're immune to the effects of what we've been doing to the climate for the past hundred years.

It's profoundly maddening when you think about the fact that scientists and environmentally-conscious laypeople like myself have been sounding the alarm about this for decades.  I'd like to hope that this new report out of Australia will shake a few people up, but our history of ignoring the experts leaves me feeling like this will get shoved under the rug, too.

Remember the character of Cassandra from Greek mythology?  She was the daughter of King Priam and Queen Hecuba of Troy, and was given a blessing and a curse by the god Apollo -- that she could see the future, but when she told people about it, no one would believe her.  Even after Troy was sacked and burned, and her parents killed -- just as she'd predicted -- still people discounted what she said.  The environmental scientists are like modern-day Cassandras, telling people what the models said would happen, and even after the models have proved correct over and over (in fact, when they were wrong, it was usually because they underestimated the effects), people still shrug their shoulders and pretend nothing's wrong.

I'd like to find a positive way to end this post, but I'm fresh out of ideas about how to do that.  The situation is dire.  Our only hope -- slim as it is -- is to elect politicians who place the global environment in first place on the priorities list.  Until we do that, I'm afraid the Cassandras will continue their fruitless prophesying, and the rest of us will continue our slide into the pressure cooker.

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I contain multitudes

One of the things that even folks conversant in the evolutionary model sometimes don't know is the extent to which we are composite organisms.

On the gross level (and I mean that in both senses of the word), there is the sheer number of cells in us that are not human.  The adult human body has about 10 trillion human cells, and (depending on who you talk to) between 1 and 3 times more bacterial cells -- intestinal flora, bacteria hitching a ride on our skin, in our mouths, in our respiratory mucosa.  Most of these are commensals at the very worst -- neither harmful nor helpful -- but a significant number are in a mutualistic arrangement with us, which is one of several reasons why the overuse of antibiotics is a bad idea.

Then there are the little invaders we can't live without -- namely the mitochondria, those tiny organelles that every high school biology student knows are the "powerhouses of the cell."  What fewer people know is that they are actually separate organisms, descended from aerobic prokaryotes that colonized our cells 2.5 billion years ago (give or take a day or two).  They have their own DNA, and reproduce inside our cells by binary fission the same way they did when they were free-living proto-bacteria.

Mitochondria [Image is in the Public Domain courtesy of photographer Louisa Howard]

But that's not all. If you're a plant (I'm assuming you're not, but you never know), you have three separate ancestral lines -- your ordinary plant cells, the mitochondria, and the chloroplasts, which are also little single-celled invaders that now plants can't live without.  But even that's not the most extreme example.  The microorganism Mixotricha paradoxa is a composite being made up of five completely separate ancestral genomes that have fused together into one organism.

It's amazing how much these relationships alter behavior, sometimes in ways that blur the definition of the word "organism."  Is Mixotricha one organism or five?  Unsurprisingly, given their history of anticipating scientific discoveries, Star Trek gave a hard look at this question with the character of Jadzia Dax.  Dax is a Trill -- an individual produced by the fusion of a humanoid host and a long-lived symbiont.  Although the symbiont can survive after the death of the host, and go on to fuse with another one, the personalities remain blended, and the symbiont brings to its new host all the memories, skills, and traits it accessed from previous ones.

Weird stuff, but not so far off from what we see down here on Earth.

But back to humans, if you're not already so skeeved out that you've stopped reading.  Because it's even more complicated than what I've already told you -- check out a paper by geneticists Cedric Feschotte , Edward Chuong and Nels Elde of the University of Utah, in which we find out that even our nuclear DNA isn't entirely human.  Feschotte et al. have shown that ten percent of our thirty-thousand-odd genes and three-billion-odd base pairs...

... came from viruses.

We usually think of viruses as pesky little parasites that cause colds, flu, measles, mumps, and so on, but they're more than that.  Some of them -- the retroviruses (HIV being the best-known example) -- are capable of inserting genetic material into the host's DNA, thus altering what the host does.  Certainly, sometimes this is bad; both AIDS and feline leukemia are outcomes of this process.  But now Feschotte, Chuong, and Elde have shown that some of our viral hangers-on have had their genes repurposed to work in our benefit.

These stowaway bits of DNA are called endogenous retroviruses (ERVs), and some of them seem to be associated with cancer.  Others have been implicated in multiple sclerosis and schizophrenia.  But what the researchers found is that not all of them are deleterious; the gene that allows us to digest starch, and (even more importantly) the gene that triggers the fusion of the developing embryo to the placenta, seem to have viral origins.

"We think we’ve only scratched the surface here on the regulatory potential of ERVs," Feschotte said.

All of which is pretty amazing.  And it definitely gives one pause when you stop to think of how we define the word "organism."  Am I a single organism?  Well, not really.  Besides my regular human cells, I've got trillions of mitochondria, each with their separate bacterially-derived genome; and ten percent of what I think of as "my DNA" came from viruses, at least some of which has then been modified into genes that I depend on to survive.  So humans -- and all living things -- are looking more and more like composite colonies of symbiotic life forms, representing a web of interrelationships that is so complex that it's mind-boggling.

So, to hell with the weird, exotic life forms from Star Trek.  I'm too busy being blown away by how bizarre and cool the life here on Earth turns out to be.

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The house of cards

I was first introduced to the idea that human history has been shaped by climate swings back in 1990, with British science historian James Burke's prescient two-part documentary After the Warming.  In part one, he tracks the (natural) ups and downs that have occurred because of gradual shifts in the Earth's orbit and rotational axis; in part two, he then looks at the effects humans are having because of our out-of-control burning of fossil fuels and use-it-once-then-throw-it-away culture of consumerism.  From my standpoint now, thirty-two years after the documentary was released, his predictions seem nothing short of uncanny, right down to the United States's steadfast determination not to do a damn thing to address anthropogenic climate change.  But he even got a lot of the more specific effects spot-on.  For example, he predicted the crazy spate of Atlantic storms that caused billions of dollars of damage and resulted in the NOAA running out of hurricane names and having to switch over to "Alpha," "Beta," and "Gamma," even getting it right down to the year it occurred (2005).  Watching it now, it's almost like it was made today by someone with a slight penchant for bending the truth, not by someone three decades ago for whom all of these were merely shrewd forecasts.

If I have one criticism of Burke, it's that he gives the impression that everything in history boils down to the climate.  Part one, entertaining and enlightening as it is, is kind of a ninety-minute long exploration of the single-cause fallacy.  That said, it's still a sobering cautionary tale.  We can't discount the effects that shifts in the climate can have on humanity.  Right now in the central and southern United States we're trapped in a heat wave that has already broken records in an area that's accustomed to summer heat; simultaneously the much-more-poorly-prepared people of western Europe are not only facing record high temperatures but droughts and wildfires.

It remains to be seen how long it'll take before the climate naysayers will finally, grudgingly, admit that we've been right all along.

Another of Burke's oversights is an interesting one; although he considers other natural phenomena, he doesn't look at the effects of volcanic eruptions on the climate.  It may be because these are drastic, but usually short-lived; long-time readers of Skeptophilia may recall a piece I wrote a while back on the effects of an eruption in Iceland in the sixth century C. E. that was the principal cause of "the worst decade in history" -- a series of plagues, famines, and catastrophically cold winters that killed an estimated sixty million people.  It took nearly a hundred years for the effects to abate, and when they did, they led into an unusually warm period (probably because of the injection of carbon dioxide into the atmosphere by the eruption).  An even bigger eruption, this one in Indonesia about seventy-four thousand years ago, is thought by some scientists to have nearly caused the human species to go extinct -- the "Toba Bottleneck" may have reduced the entire human population of the Earth to under ten thousand individuals.  (This conclusion, however, is still under serious debate amongst scientists.)

The reason all this comes up is because of an article at the site Yale Climate Connections sent to me by a loyal reader, which describes the historical impact of an eruption I'd never heard about -- the eruption of the Alaskan volcano Mount Okmok in 43 B. C. E.  

The caldera of Mount Okmok [Image courtesy of photographer Christina Neal and the USGS]

It was another massive one, with global effects.  Tree ring analysis from the White Mountains of California give evidence of the second-coldest winter on record.  Written accounts from Rome describe cold, dry summers that caused agricultural failures several years running; in Egypt, it manifested as the loss of the annual floods of the Nile River three times in a row, resulting in devastating drought and famine.

This, in turn, contributed to the collapse of the Ptolemaic Empire in Egypt, then ruled by the famous and charismatic Queen Cleopatra VII.  

It's a little alarming to see how quickly the climate can change, and the havoc such changes can wreak.  It's why people like me have been sounding the alarm for decades, urging caution instead of what we've been doing, which is blundering about as if everything around us is permanent, as if we're guaranteed a clement climate and plenty of food and water.  All you have to do is to look at history to realize how precarious things are.  While I won't go as far as James Burke did in attributing damn near everything to the climate, there's no denying that in many ways the interlocking systems of our planet have the fragility of a house of cards.  Some things -- such as volcanic eruptions and orbital shifts -- we can't do anything about.  But once you see the effects of climate change on the history and habitability of the Earth, I don't see how you wouldn't come away absolutely convinced that we better do everything we can to protect the part of it we can do something about.

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Cryptids down under

Friday's post, about alleged sightings of a Bigfoot-like creature in Kent, England, prompted a loyal reader of Skeptophilia to send me an email with a link captioned, "Don't forget us Aussies!"

The link was to an article at the site news.com.au, entitled, "'These Things Are Dangerous': Dean Harrison Claims Yowie Responsible For Missing People," wherein we find that the Australian version of Bigfoot -- the Yowie -- is not content with merely scaring the shit out of you, it actually is trying to kill you.

This should come as no surprise, because Australia has a well-deserved reputation for having dangerous wildlife.  Not only do they have six-meter-long saltwater crocodiles and abundant great white sharks, Australia is home to four of the top-ten deadliest snakes in the world (the Eastern Brown Snake, the Mainland Tiger Snake, the Coastal Taipan, and the Inland Taipan), the most venomous jellyfish known (the box jelly), and the most aggressive and dangerous bird in the world (the cassowary).  For fuck's sake, they even have a plant (the gympie-gympie) with hypodermic-needle-like hairs that inject a neurotoxin, resulting in excruciating pain that can last months.

"Don't forget about the Drop Bears," an Australian friend of mine told me.  "You visit Australia, you have to be constantly on the lookout for Drop Bears."

So I guess the Australian Bigfoots have to be pretty fierce just to fit in.

Harrison doesn't just collect Yowie sightings from other people, he's actually seen them himself.  On one occasion, he says, he barely escaped unscathed.  He was out for an evening run in the town of Ormeau, on the Queensland coast, and suddenly heard a terrifying noise.

"I heard all this crashing coming through the bush behind me and it sounded like a group of kids just trashing the place," Harrison said.  "The sound of snapping branches and crushing leaves started to get closer until a large figure emerged about ten meters behind me.  I got these unexplainable chills which are what we call the nameless dread … and like a rabbit in spotlights, basically, my whole body just locked up."

I dunno, "unexplainable" is not the word I'd use for being scared if a huge creature emerged from the underbrush near me at night.  Myself, I think it'd have been entirely explainable if he'd pissed his pants and then had a brain aneurysm.

"I didn’t know how I knew, but I knew I was in danger… and I knew that if I turned around and made direct eye contact, things would get exponentially worse." Harrison said.  So he broke into a sprint, and the creature started chasing him.  "He’s yelling and he’s roaring and he’s doing some sort of almost like a talk over the top and on every footstep … his diaphragm in his chest would bounce."  Which is pretty good detail to notice when you're running away from a giant proto-hominid at night.

"Before I knew it, he’s right next to me.  I thought, this is it, this is the end of my life.  I’m about to die right now."

Fortunately, though, he spotted a streetlight in the distance, and hauled ass toward it.  The Yowie for some reason decided not to pursue, and Harrison lived to squatch another day.

One of Harrison's infrared shots of a Yowie near Gold Coast, Queensland

The Yowie has a long history, and legends of encounters go back to Indigenous Australians far predating European colonization.  But the sightings persist, and Harrison says he gets a new report from somewhere in the country "every second day."

He's still waiting for unequivocal hard evidence, though (as are we all).  At least here we have a big country with a huge amount of wilderness and lots of places to hide.  So the idea of a significant population of some large mammal species living there and not leaving behind any traces is at least more plausible than the same thing existing in, say, southeastern England.

But the article concludes rather sadly that we still don't even have a clear photograph of a Yowie, and we'll have to keep looking.  It ends with an adjuration for Yowie-seekers not to confuse Yowies with the Bunyip, another bizarre denizen of the Outback.

Myself, I don't see how you could.  The Yowie is a three-ish meter tall apelike creature, while here's a 1935 illustration of the Bunyip, by Gerald Markham Lewis:

I'm not seeing much similarity, although there is the commonality that either would inspire you to think, "Holy shit, I'm gonna die."

In any case, that's our exploration of cryptozoology in The Land Down Under.  If I'm ever lucky enough to visit Australia, I'll make sure to do some Yowie-hunting.  I'll also keep a weather eye out for Drop Bears.

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Living crystals

Starfish are odd creatures in just about every respect.

They belong to a phylum called Echinodermata, which is Greek for "spiny skin" and also includes such weird animals as sea urchins, sand dollars, brittle stars, sea cucumbers, and crinoids (also called "sea lilies" or "stone lilies" because they look more like some kind of weird undersea plant than they do animals).  One of the big surprises for my AP Biology students, during the unit on zoology, was that echinoderms are our closest non-vertebrate relatives.  The old distinction of vertebrate versus invertebrate turns out to reflect less of a real genetic and evolutionary split than the distinction between protostome and deuterostome; the former includes insects, crustaceans, arachnids, mollusks, annelids (e.g. earthworms), and nematodes (roundworms), while the latter is just the echinoderms and vertebrates such as ourselves.

The names protostome and deuterostome, if you're curious, are also Greek; they mean (respectively) "first mouth" and "second mouth," referring to the order in which the openings of the digestive tract form.  In protostomes, when the beachball-shaped early embryo forms an inpocket that will lead to the formation of the gut, that first opening will eventually become the mouth; the anus forms when the inpocket tunnels its way through and comes out of the other side.  In deuterostome, it happens the other way around, but early embryologists evidently thought that "mouth second" sounded more genteel than "ass first," and that's how we ended up called "deuterostomes."  (I remember the shocked look on one of my students' faces when I told the class about this fun feature of embryonic development.  She said, wide-eyed, "So, at some point, all humans are just... a butthole?"  I deadpanned back, "Yup.  Unfortunately, some people never get past that stage.")

You might wonder how echinoderms can look so different from vertebrates if we're actually on the same branch of the animal family tree.  In fact, echinoderm larva are clearly bilaterally symmetric, just like vertebrates are; they largely lose that symmetry as they mature, although the apparent pentaradial symmetry of a starfish is kind of an illusion, because they do have organs (like the water intake organ, or sieve plate) that are offset to one side.  But they lose more than their symmetry; the adults have no true circulatory system (all they end up with is a set of what are essentially water pipes), no central nervous system (just a nerve ring and branched peripheral nerves), and the simplest of digestive tracts.  This despecialization seems to underlie their wild ability to regenerate lost or damaged limbs -- a capacity that has been under intensive study because of the possible applications to medical science.

[Image licensed under the Creative Commons Copyright (c) 2004 Richard Ling, Blue Linckia Starfish, CC BY-SA 3.0]

The reason all this comes up is because of yet another bizarre and beautiful feature of starfish, just discovered at MIT.  When they're still very early in embryonic development, and resemble spherical glass beads, they exhibit a peculiar behavior -- they spin, creating tiny vortices in the water and drawing other nearby embryos in.  Eventually they self-assemble into a living crystal -- a regular, tightly-packed lattice of embryos all spinning in the same direction.  They undergo peculiar ripples that the researchers call "odd elasticity" -- odd because the oscillations aren't damped down by the water's drag, but continue to propagate through the entire crystal, like some sort of biological standing wave pattern.

"The spontaneous, long-lasting ripples may be the result of interactions between the individual embryos, which spin against each other like interlocking gears," said Alexander Mietke, who co-authored the paper on the phenomenon that appeared last week in Nature.  "With thousands of gears spinning in crystal formation, the many individual spins could set off a larger, collective motion across the entire structure."

The benefit to this behavior isn't known.  One possibility is that the formation of these crystals makes it less likely that the embryos will be eaten by predators, but that's just speculation.  At the moment, though, it's enough to wonder at the intricacy and beauty of these odd creatures, our distant cousins on the evolutionary family tree.

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A modern Mary Celeste

There's something compelling about a story with no definitive answers.  It's no wonder a lot of our favorite works of fiction have an element of mystery, and in some of them, the loose ends are never completely tied up.  Think of how many of our spooky Tales Around A Campfire end with a line like, "... and no one ever found out what happened to the missing teenagers."

In real life, though, unsolved mysteries have a way of inviting wild speculation, usually based on evidence for which even the word "slim" is an overstatement.  Consider, for example, the off-the-rails "explanations" people came up with to account for the fact that even powerful telescopes couldn't see any surface detail on the planet Venus.  Here's how Carl Sagan described one of these lines of thought, in the episode "Heaven and Hell" of his wonderful series Cosmos:

I can’t see a thing on the surface of Venus.  Why not?  Because it’s covered with a dense layer of clouds.  Well, what are clouds made of?  Water, of course.  Therefore, Venus must have an awful lot of water on it.  Therefore, the surface must be wet.  Well, if the surface is wet, it’s probably a swamp.  If there’s a swamp, there’s ferns.  If there’s ferns, maybe there’s even dinosaurs.

Observation: I can't see a thing.  Conclusion: dinosaurs.

What got me thinking about this tendency is a curious story out of Cambodia that hit the news earlier this week.  On Koh Tang Island, in Preah Sihanouk Province, on July 12, a "ghost ship" ran aground -- no sign of the captain and crew, no markings indicating where the ship had originated.  Three lifejackets were found washed up on a nearby beach, but there are no bodies, nothing to indicate what happened to the ship and its passengers.  Stormy conditions have made further investigations impossible for the time being.

Immediate comparisons were made to the most famous of all "ghost ships," the Mary Celeste.  The Mary Celeste set sail from New York City on November 7, 1872, headed for Genoa, Italy.  Being in the days before shipboard radio, nothing more was heard from it until it was found drifting in the Azores a month later.  It was completely deserted.  The last entry in the ship's log was ten days earlier, and indicated nothing amiss.  It was amply provisioned with food, and none of the crew members' belongings were disturbed, as you'd expect if it had been captured and boarded by pirates.  There was no damage to the ship itself; it looked as if somehow, the captain and crew had simply... evaporated.

And to end the tale in appropriate campfire story fashion: no one ever found out what happened to the crew, and none of them was ever seen again.

The story of the Mary Celeste is certainly puzzling and creepy, but most rationalists still think there's a logical (and natural) explanation for what happened to it.  The same is true in the case of the Cambodian ghost ship.  Here, the most plausible answer is probably either that it was a ship that had been put out of service (the lack of markings and identifications suggests that the "service" might have been hauling illicit cargo, possibly drugs), and either had accidentally slipped its moorings and drifted off, or had been scuttled deliberately.

But just as with Carl Sagan's "I can't see anything = dinosaurs" example, the lack of anything definitive has touched off a lot of wild speculation about what happened to the ship.  Amongst the "explanations" I've seen:

• the Bermuda Triangle has opened a branch office in the Indian Ocean, and the crew went through a portal to parts unknown
• the crew were abducted by aliens
• the ship got too close to an island run by the Illuminati, so the crew had to be eliminated
• the ship was attacked, and the crew eaten, by (choose one): a giant squid, a marine version of the Loch Ness Monster, beings from Atlantis, Cthulhu

Okay, just hang on a moment, here.

Let's stop and consider another quote, this one from astrophysicist Neil deGrasse Tyson: "Remember what the 'U' in 'UFO' stands for...  If something is 'unidentified,' then that's where the conversation should stop.  You don't go on and say 'so it must be' anything."  There's (at present) no real evidence for what happened to the ghost ship, so we should put any further speculation on hold for as long as need be.

And keep in mind that here, it's not even like most UFO sightings, which are one-offs that leave behind no traces and no chance of a repeat performance; the Cambodian authorities have the actual ship, meaning at some point when the conditions improve they'll be investigating further.  All we have to do is wait a while and see what they discover.  Chances are they'll find evidence that it's an illicit/unregistered cargo ship that was used in drug-running.  Which will send the aficionados of the Bermuda Triangle, Atlantis, and Cthulhu sulking off to their rooms...

... until the next mystery, at which point they'll all come roaring back.  Like they have every other time something odd happens.

It'd be nice if sometimes we could just let mysteries be mysteries.  Saying "we don't know, and might not ever know" isn't satisfying, but as good skeptics we have to be willing to say it when it's warranted.  I won't say that I'm not fascinated by cases like the Mary Celeste, where there really seems to be no plausible explanation, but intellectual honesty forces us to put aside our wild imaginings and accept that sometimes, there may never be a definitive answer.

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