Heap of trouble

In my AP Biology class, we did a lab that involved extracting chlorophyll from spinach leaves.  The first step was to grind the leaves into a paste with a bit of solvent, which we did the old-fashioned way using a mortar and pestle.

The instructions said to add a "small amount of fine sand" to the leaves (to act as an abrasive, facilitating the breakup of the tough cell walls), and one of my students -- a little on the tightly-wound side, as I recall -- asked how much to add.

"Doesn't matter," I said.  "Some.  A pinch.  You're going to filter it out at the end anyhow."

This didn't satisfy her.  Everything else was measured to high accuracy, so the sand should be, too.  How much sand was "some"?

I grabbed a pinch of sand between my thumb and index finger and tossed it into the mortar.

"There you go," I said.  "All fixed."

She gave me the suspicious side-eye, as if by my insouciance I had ruined her chance of getting good results.  As I recall, she did just fine on the lab, but I don't think she quite trusted my lab technique afterward.

A couple of amused students who overheard the conversation got into a discussion about the imprecision of measuring-words in English, and decided to fix matters by constructing a list:

2: a couple
3: a few
4: some
5: a bunch
6: a lot
7: quite a lot
8: a helluva lot
etc.

I recall that they got up to 20, which was "a shitload."

After showing the list to me, they did admit that these designations could shift depending on what you're talking about.

What I didn't realize until recently was that this discussion, as lighthearted (honestly, ridiculous) as it was, touched on a paradox that has been around for at least 2,400 years -- the Sorites Paradox.  The name comes from the Greek word σωρός, meaning "heap," and is attributed to the fourth century B.C.E. philosopher Eubulides of Miletus, who is said to have formulated it.  It goes something like this:

Let's say you have a million grains of sand in a pile, sitting on the left side of the table.  Nearly everyone would agree that this constitutes a "heap of sand."  On the right side of the table, you have a single grain of sand.  No one, I suspect, would say that one grain of sand is a heap.  Okay, so that means that if you remove one grain at a time from the left-hand side, at some point it changes from "a heap" to "not-a-heap."

When does that happen?

It's not just the word heap that has this problem.  Take away one teaspoonful of water at a time from the ocean, and at some point -- admittedly, it'd take a while -- what's left would no longer be an "ocean."  When does that change happen?

How about old?  Along the pathway of life, I think we can all agree that a fifteen-year-old is "young," and a ninety-year-old is "old."  So, when do things flip?

I'm currently sixty-five, and I will not admit to being old, so anyone inclined to answer should keep that in mind.

This also relates to another famous paradox, the Ship of Theseus.  If you take Theseus's ship and replace, one at a time, each of the components that make it up, at what point does it cease to be the original ship?

One solution to the Sorites Paradox is simply to declare these things a continuum, which therefore renders such questions essentially meaningless.  The problem is, the number of grains of sand in a heap isn't a continuum; it's necessarily an integer (you can't have a heap made of 1,827,793-and-a-half grains of sand).  Neither, for that matter, are the pieces of a ship.  So while this might be a reasonable response in cases of true continua (such as age, water volume, or the colors of light in a rainbow), it doesn't work in systems with discrete states.

So maybe it's just unanswerable, and relies simply on usage -- language is inherently vague, and there's nothing to be done.  This is the stance of British philosopher Timothy Williamson and others, who solve the Sorites Paradox by shrugging their shoulders; there is a point where a heap becomes not-a-heap, but where the point lies is unknowable.

While all this might seem like nothing more than philosophical noodling, it has its serious applications.  The question of when depictions of sex in movies cross the line into obscenity or pornography (therefore suggesting that they should be subject to censorship) made it all the way to the Supreme Court, which ruled that the movie in question -- Louis Malle's The Lovers -- wasn't pornography, even if the court couldn't come up with a good definition of where the line was.  "I could never succeed in intelligibly [defining pornography]," Justice Potter Stewart famously said, "but I know it when I see it."

The Sorites Paradox also has a strange connection to evolutionary biology, and one that knocks a neat hole into the creationists' assertion that every species represents a "kind" that is in some sort of hard-and-fast, unchangeable box.  The issue is with ring species, of which there have been several described (two well-studied ones are circumpolar populations of gulls of the genus Larus, and populations of the Greenish Warbler around the Himalayas).  In a ring species, adjacent, similar-but-distinct groups can interbreed, and thus by definition should belong to the same species.  The problem is, the ends of the ring have diverged enough that where they do overlap, they no longer can interbreed, and thus should be separate species.  But where do you draw the line?  No matter where you do, you end up separating individuals that (by the canonical definition of the word species) should belong together.

Or -- to take Williamson's approach -- maybe the problem is trying to force a fuzzy reality to conform to limited, inaccurate use of language, and the word species is simply kind of a mess.  This is my opinion on the matter; I tend to agree with my evolutionary biology professor, who memorably said, "The only reason we came up with the concept of species is that we have no near relatives."

A ring species of salamanders in California [Image licensed under the Creative Commons Thomas J. Devitt, Stuart J.E. Baird and Craig Moritz, Ensatina eschscholtzii ring species, CC BY 2.0]

Anyhow, that's today's consideration of a philosophical problem that has been around for over two thousand years, and thus is clearly above my pay grade to weigh in on.  Not that this ever stops me.  Now, y'all'll have to excuse me, because I need to go work in my garden spreading the heap of bark mulch we just had delivered, an amount that is clearly "a shitload."

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The Estes method

In somewhat the same vein as yesterday's post, which was about the capacity of subsonic standing waves to induce the sensations we often associate with a haunting, today we have: a way to pick paranormal messages out of ambient (and random) noise.

You've probably heard about the idea of electronic voice phenomena, which was popularized as a ghost-hunting method by Latvian paranormal researcher Konstantīns Raudive in the 1970s and has become a standard tool in the kit ever since.  The idea is that you place a recording device of some kind -- it started out with reel-to-reel, then cassette tape recorders, and finally moved on to digital voice recorders -- in an allegedly haunted location, leave it running, and later listen to the recording for any anomalous sounds.  Adepts claim that they hear human voices.

The method was used to great effect in the brilliant Doctor Who episode "Hide," although it turned out that what Clara and the Eleventh Doctor were talking to wasn't a ghost, it was a time-traveler trapped in an alternate universe.  As one does. 

Some of these EVP are more convincing than others, but all of them tend to be muffled and slurred, and to benefit greatly from the phenomenon of suggestion -- once someone tells you that the voice is a ghost saying "I died in 1859" you're much more likely to hear the message.  This is the same thing that occurred with the foolishness surrounding backmasking -- that supposedly, rock bands were including satanic messages in their music that could only be understood consciously if you played the song backwards, but could be somehow picked up subliminally even if you heard it played forwards.  (One of the most popular claims of backmasking involved Led Zeppelin's famous "Stairway to Heaven.")  The problem is, even played backwards, the messages are pretty damn garbled -- but miraculously clear up when you know ahead of time what it's supposed to be saying.

As James Randi put it, "You can't miss it if I tell you what's there."

Graphical plot of white noise waveform [Image licensed under the Creative Commons Omegatron, White-noise, CC BY-SA 3.0]

There's apparently a new way to approach all this that's becoming popular amongst the ghost hunting crowd, and I learned about it from British paranormalist Ashley Knibb's website just yesterday.  It's called the "Estes method," named after Estes Park, Colorado, home of the Stanley Hotel (made famous in The Shining).  The idea here is that a volunteer "receiver" is blindfolded and puts on headphones connected to a radio that's set on "scan" mode, so the only auditory input (s)he gets is blips and fragments of speech or music, interspersed with white noise.  Another volunteer, the "recorder," asks questions -- not of the receiver, but of any ghosts that happen to be present -- while the receiver (who, presumably, can't hear the receiver) reports any interesting phrases heard from the random radio input, which the recorder then writes down.

The claim is that this isolates the receiver; (s)he relies only on any ghosts present to jigger about with the radio and use its audio output to answer what the recorder is asking.

Well, okay.  There are a couple of problems with this, and to his credit, Knibb mentions both of them (although you get the feeling he is still inclined to think that something paranormal may be going on here).

The first is that how the random phrases picked up by the receiver are interpreted afterward is very much dependent upon the subjective opinions of the ones doing the interpretation.  You may recall the famous experiment done by Carl Sagan in a high school class, where he told the students that their birthdates and times had been used to draw up astrological charts and create a personality profile for each of them, and handed out cards with the results.  The students were then asked to rate how accurately it described them, from zero to ten.  Not a single card received a score lower than six; most were between eight and ten.

Wow, astrology vindicated, right?

Not exactly.  Sagan then had the students exchange cards with a neighbor -- and it turned out they'd all been given the same personality profiles.

The point is, when we are given some random piece of text, we're all too likely to interpret it as if it means something -- especially if we walked into the situation already primed to think it does.

The second problem, of course, is exactly the same as what I described in yesterday's post; apophenia, our built-in tendency to find order in random input.  The receiver in the Estes method is trying his/her hardest to listen for anything that sounds meaningful; after all, that's why (s)he's there.  It's not a far step to consider the possibility that the receiver might (even if unconsciously) create something meaningful out of what is, honestly, chaos.

Again, as with yesterday, I'm not accusing anyone of anything underhanded.  Hoaxes aren't even necessary, given how easily our own sensory-perceptive systems can play us false.

So I'm not thinking the Estes method is going to convince anyone who's not already convinced.  As far as the ghost hunters go, no harm if it amuses you, but it still doesn't meet the minimum criterion required for acceptable evidence in a scientific setting.

Me, I'm still in the camp of Andrew MacPhee, the hard-nosed skeptic in C. S. Lewis's novel That Hideous Strength:

"My uncle, Dr. Duncanson," said MacPhee, "whose name may be familiar to you — he was Moderator of the General Assembly over the water, in Scotland — used to say, 'Show it to me in the word of God.'  And then he’d slap the big Bible on the table.  It was a way he had of shutting up people that came to him blathering about religious experiences.  And granting his premises, he was quite right.  I don’t hold his views, Mrs. Studdock, you understand, but I work on the same principles.  If anything wants Andrew MacPhee to believe in its existence, I’ll be obliged if it will present itself in full daylight, with a sufficient number of witnesses present, and not get shy if you hold up a camera or a thermometer."

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Bad vibrations

A point I've made here more than once is that my doubting many claims of the paranormal isn't because I think it's necessarily impossible, but because our sensory-interpretive systems are so fundamentally flawed.

I mean, they work well enough, for most of us most of the time.  But not only do we have the capacity to miss a great deal of what's going on around us -- as the famous experiment in which a great many test subjects failed to notice a guy in a gorilla suit showed -- what we do sense is all too easy to misinterpret or remember incorrectly.  This is why if someone comes to me with a claim of some supernatural occurrence or another, I'm going to ask for some kind of hard, scientifically-admissible evidence.  To quote astrophysicist Neil deGrasse Tyson, "I need more than 'you saw it.'"  Neither he nor I are accusing anyone of lying or perpetrating a hoax; the problem is that eyewitness testimony is all bad, even if you mean well and are trying your hardest to be honest.

[Image is in the Public Domain]

To throw another monkey wrench into the situation, consider the recent paper by psychologist Rodney Schmaltz of MacEwan University.  Schmaltz became interested in the possible role of subsonic vibrations in claims of haunting; there was a case in England where a medical research building was claimed by several workers to be haunted, in one case by a "gray form that materialized, floated across the room, and vanished."  More than one person saw the apparition, and several described a sensation of chill, as if they were being watched.

The culprit turned out not to be a ghost, but a furnace fan that had set up a subsonic standing wave in the basement.  The frequency of the wave was around twelve Hertz -- so below the range humans can hear -- but created resonant vibrations in our eyes and ears that could be sensed by the brain.  The result: eerie hallucinations, altered perception, and feelings of unease.

What Schmaltz did was try to see if there was a way to measure the human response to infrasound, by setting up test subjects to listen to recordings of music through headphones.  Half the test subjects listened to calm instrumental music, and the other half eerie recordings that could have been the soundtracks of horror movies.  What the subjects didn't know, though, was that half of each of the audio tracks had been altered to include infrasound.

The results were incontrovertible.  The subjects exposed to infrasound weren't aware of it consciously, but responded to it regardless.  Also, it didn't matter what the audible component was.  If they were exposed to infrasound, they reported feeling unsettled and unhappy, and -- most strikingly -- a saliva test showed elevated levels of the stress hormone cortisol.

“Whether they were listening to calming instrumental music or something more unsettling, the infrasound shifted their mood and their stress response in a negative direction,” Schmaltz said.  “In plain terms, you cannot hear infrasound, but your body and your mood appear to respond to it anyway, and the response tends to be unpleasant.”

Schmaltz suggests that a lot of the reports of ghosts in old buildings might be nothing more than infrasound coming from antiquated boilers, furnaces, and plumbing -- aided, of course, by the fact that we're already primed to expect something paranormal from such places by a hundred years of scary movies set in run-down mansions.

Even knowing all of this, though, probably wouldn't make a whit of difference to our actual responses in such a situation.  Because that's the other part of the problem, isn't it?  Our emotional reaction to a particular set of circumstances has a way of derailing our higher brain functions, especially when that reaction is "OMG a ghost, run!"

And unfortunately, that applies not just to those Crazy Kids and Their Stupid Dog, but to skeptical rationalists.

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The case of the missing scientists

Our capacity for seeing patterns is absolutely critical.

It's easy to see how survival in a risky world could hinge on noticing clues in the environment, then putting them together correctly.  The key, though, is the word correctly.  When you have a built-in mechanism for interpreting sensory cues and recognizing danger, it can easily go awry.  But -- and here's the most important point -- in general, the evolutionary cost of overreacting is almost always way less than that of underreacting.  To use the oft-quoted example, for your average proto-hominin on the African savanna, it's better to hear a rustle in the grass, take fright and bolt, and have it turn out to be a fluffy bunny, than to shrug it off and stay put when it's a hungry lion.  

Or, worse still, not to notice it at all.

This tendency remains with us, lo unto this very day, and it's astonishing how badly it can backfire.  We look around us, assemble the information we have, and all too often put the pieces together wrong -- especially when the pattern that emerges is scary.

And especially especially when we're encouraged to do so by sensationalist media who make their money from clicks, and politicians who benefit by keeping their constituents frightened and distracted.

Take, for example, the current kerfuffle over all the scientists who have allegedly disappeared (or died) recently.  They all, we are told, worked with classified secrets.  The words "mysterious circumstances" have been thrown about.  The implication -- sometimes, the explicit claim -- is that the scientists' fates are all linked, part of a massive conspiracy to silence "people who know too much," or (perhaps) who were about to blow the whistle on some even bigger conspiracy and implicate Important People.

The story hit the news when a retired United States Air Force general, Neil McCasland, left his house in Bernalillo County, New Mexico on foot in late February, and never returned.  A search was conducted, but no trace of him was ever found.  McCasland, they said, was "involved in UFO research," and this was somehow relevant to his disappearance.  Then there's Monica Jacinto Reza, who was director of materials processing at NASA/JPL, who vanished while hiking in the Angeles National Forest in June of 2025.  I'll admit her disappearance was odd; she was an experienced hiker and was accompanied by two other equally able friends, had been seen about ten meters back on the trail and had smiled and waved, but when her friends looked back shortly afterward, Reza was gone.

Once again, searchers came up empty-handed.

Carl Grillmair, an astronomer and exoplanet researcher at Caltech, was murdered in mid-February of this year.  Nuno Loureiro, a plasma physicist at MIT, was shot and killed in December of 2025.  Here are a few others that often get thrown into the mix:

• Amy Eskridge, died in June of 2022; Eskridge was an "anti-gravity researcher"
• Michel David Hicks, a planetary researcher at NASA/JPL, died in July of 2023
• Anthony Chavez, of the Los Alamos National Laboratory, disappeared in May of 2025
• Jason Thomas, assistant director of chemical biology at Novartis, drowned in Lake Quannapowitt, Massachusetts in December of 2025

So the relevant question here is: does this make a pattern?

The answer is no.  Not even close.  Okay, McCasland and Reza are curious circumstances, to say the least; but McCasland had medical problems, and even his wife wrote a piece pleading with people to stop the "misinformation circulating about Neil and his disappearance."  As far as Reza... well, I'm an experienced back-country hiker myself, and the wilderness is a big, big place.  If you don't think it's possible someone -- even a dedicated backwoods-explorer -- could get inextricably lost and die out there, you haven't actually experienced what the back country is like.

How about the rest?  Well, the police actually arrested the perpetrator of Grillmair's murder, and it was pretty clearly a burglary that went badly wrong.  Loureiro's killer was almost certainly Cláudio Manuel Neves Valente, who knew Loureiro personally and seems to have had a grudge against him -- Valente had gone to college with Loureiro and graduated first in his class, but unlike Loureiro, his career never took off.  Valente was described as "often unhappy or even angry," and eventually snapped; the day after killing Loureiro, he went to Brown University, killed two students and wounded nine others, then turned the gun on himself.

As far as the others, Eskridge wasn't a government employee at all, just a fringe-y pseudoscience content creator; she'd been in chronic pain for years, and it's nearly certain she committed suicide.  Hicks died of natural causes from a chronic medical condition.  Chavez wasn't a scientist, but a construction foreman, and hadn't worked for Los Alamos for years.  Thomas, a medical researcher who had zero to do with space science, suffered from long-term depression, and his drowning death was ruled as an accident.

So what looked like a pattern turns out to be nothing much at all.  But of course that's not calming anyone down.  Karoline Leavitt, who hasn't been within hailing distance of reality for years and wouldn't recognize the truth if it came up and bit her on the ass, says there are "legitimate questions about these troubling cases" and that "no stone will remain unturned" in unmasking the conspiracy behind it all.  Especially if it turns out to have nothing to do with Jeffrey Epstein.  Podcaster Walter Kirn goes further, saying "What is going on seems to be an enemy action...  [The missing individuals were involved] in the most advanced realms of space-rocket propulsion and, you know, Air Force–NASA–type endeavors."  House Oversight Committee Chairman James Comer said that "something sinister could be happening."  Then Missouri Representative Eric Burlison got involved -- you may recall that last year, Burlison made a name for himself by claiming that the Nephilim were real, and the Smithsonian Institute was covering it up, so his grasp on reality is even more tenuous than Karoline Leavitt's -- and said the whole thing had to do with the fact that all of the victims, alleged and otherwise, knew classified stuff about UFOs.

And we're off to the races.

[Image licensed under the Creative Commons SkepticalScience, Conspiracy Theories Fallacy Icon, CC BY-SA 4.0]

It's pretty clear that what we have here is a consortium of the usual kooks and conspiracy theorists teaming up with a bunch of politicians who are desperate to distract everyone from the fact that their policies have directly led to an economic disaster, and that the upper leadership was involved in a vicious sex trafficking ring, so they're putting 2 and 2 together and coming up with 54.

Like I said... as usual.

In any case, if you see anyone posting this nonsense as serious evidence of a huge conspiracy, I'd be much obliged if you'd set them straight.  You can even send 'em a link to this post, if you think it'll help.

After all, we have enough real stuff to worry about at the moment.  There's no need to make shit up.

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The Black Monk of Pontefract

One of the difficulties with discouraging bogus claims of the paranormal is the profit motive.

A lot of it, of course, is that the money that stands to be made can be significant.  There's not only the possibility of writing about alleged supernatural encounters, and/or making films about them, there's also paranormal tourism -- and I'm not just talking about the "ghost walks" that happen pretty much every night in every big city the world over.

I ran into a good example of this just yesterday when I happened upon a link to the story of the "Black Monk of Pontefract."  This apparition has been called "the most violent poltergeist in Britain," and is seen at 30 East Drive, Chequerfield Estate, Pontefract, West Yorkshire.

The story began when a couple named Jean and Joe Pritchard, and their children Phillip and Diane, moved into the house in 1966.  Shortly afterward, the entire family -- along with Jean's mother Mrs. Scholes, and a neighbor named Marie Kelly -- started experiencing bizarre occurrences.  Sometimes when the kitchen tap was turned on, green foam came out instead of water.  A wardrobe in Phillip's room suddenly started swaying back and forth, thumping on the floor.  Puddles of water appeared in various locations around the house.  Scariest of all, Marie Kelly was locking up the house -- she was looking after it while the Pritchards were away -- and found that Joe and Jean's wedding photograph had been slashed.

There was a lull for a while, but soon events picked up again, and in fact got way worse.  Food left on counters showed bite marks.  Light switches flickered on and off with no one there.  The family members heard footsteps, and saw objects thrown through the air.  Worst of all was when the local vicar came and tried to talk to the culprit -- and a candlestick floated up into the air, followed by the entire china closet falling over, smashing everything inside.

The haunting had numerous witnesses.  Joe Pritchard's sister Maude Peerce, a vocal disbeliever in paranormal phenomena, said as much while in the house -- and the next thing she knew, an unseen hand had dumped an entire pitcher of milk on her.  René Holden, Jean Pritchard's sister-in-law, saw a whole carton of eggs fly through the air and smash against the kitchen wall.

It was only after this had been going on for some time that the Pritchards actually saw the entity itself.  It was, they said, a figure wearing a dark robe and cowl, like a monk's habit.  This was the point that the paranormal investigators got involved, in the person of Tom Cuniff of the Doncaster Psychical Research Group.  He got made contact with the perpetrator, he said -- it was the ghost of a monk who had been hanged during the reign of Henry VIII for the rape and murder of a teenage girl, and whose angry spirit still resided there.  It even got the attention of novelist Colin Wilson, who visited the house in 1980.  "The ground itself contains some peculiar force that favours 'manifestations,'" Wilson wrote.  "The early haunting was triggered by Phillip and by his psychological tension.  The 'entity' remained in the area until Diane – who herself seems to possess undeveloped mediumistic powers – could provide the energy it needed to manifest itself."

[Image is in the Public Domain]

The house has figured prominently in books and at least one film.  But here's where the profit motive comes in; shortly after the film (When the Lights Went Out) was released, producer Bill Bungay bought the house for £80,000 -- and rents it out to thrill-seekers and paranormal investigators for a cool £300 per person per night.

It's currently booked up two years ahead, with a waiting list as long as your arm, despite the fact that you have to sign a hold-harmless waiver before you can stay there.

Okay, so what's going on here?

As I've said many times before, I'm not saying the paranormal is impossible.  Thus far, the evidence I've seen does not meet the minimum standard that would be required to convince a rationalist skeptic, but that's as far as I'll go.  Present me with better quality evidence, and I'll have no choice but to change my mind.

Here, though... I see very little that couldn't be accomplished by fakery.  If it is a hoax, which of the eyewitnesses were dupes and which were in cahoots with the perpetrators is anyone's guess; I'm not going to point any fingers.  I've just seen too many examples of "True Tales of the Supernatural" that turned out to be some mix of trickery and gullibility to dismiss the possibility out of hand.  And considering how many honest-to-goodness skeptics are out there, willing to investigate, you'd think if there really was a honest-to-goodness haunting that was this blatant and in-your-face, it'd be a shoo-in to win someone James Randi's million-dollar prize for proving a paranormal claim under scientifically-acceptable conditions.

So I'm still dubious.  Especially -- to return to my original point -- considering how much money there is to be made from the Black Monk's existence.

Anyhow, that's our creepy tale for the day.  Even if I'm not convinced by it.  And if I end up getting pelted by eggs or having my china closet fall over today, I guess it's no more than I deserve.

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No boys allowed

Sexual reproduction may be a gamble -- requiring two willing participants being in the same place at the same time -- but its advantages outweigh the risk.

And I'm not just talking about the fact that it's kind of fun.

Asexually-reproducing organisms, like many bacteria and protists, some plants and fungi, and a handful of animals, have the advantages that it's fast, and only requires one parent.  There's a major downside, however; a genetic phenomenon called Muller's ratchet.  Muller's ratchet has to do with the fact that the copying of DNA, and the passing of those copies on to offspring, is not mistake-proof.  Errors -- called mutations -- do happen.  Fortunately, they're infrequent, and we even have enzymatic systems that do what amounts to proofreading and error-correction to take care of most of them.  A (very) few mutations actually lead to a code that works better than the original did, but the majority of the ones that slip by the safeguards cause the genetic message to malfunction.

It's called a "ratchet" because, like the handy tool, it only turns one way -- in this case, from order to chaos.  Consider a sentence in English -- space and punctuation removed:

TOBEORNOTTOBETHATISTHEQUESTION

Now, let's say there's a random mutation on the letter in the fourth position, which converts it to:

TOBGORNOTTOBETHATISTHEQUESTION

The message is still pretty much readable, although the second word is now spelled wrong.  But most of us would have been able to figure out what it was supposed to say.

Now, suppose a second mutation strikes.  There is a chance that it would affect the fourth position again, and purely by accident convert the erroneous g back to an e, but that likelihood is vanishingly small.  This is called a back mutation, and is more likely in DNA -- which, of course, is what this is an analogy to -- because there are only four letters (A, T, C, and G) in DNA's "alphabet," as compared to the 26 English letters.  But it's still unlikely, even so.  You can see that at each "generation," the mutations build up, every new one further corrupting the message, until you end up with a string of garbled letters from which not even a cryptographer could puzzle out what the original sentence had been.

Sexual reproduction is a step toward remedying Muller's ratchet.  Having two copies of each gene (a condition known as diploidy) makes it more likely that at least one of them still works.  Many genetic diseases -- especially the ones inherited as recessives -- are losses of function, where copying errors have caused that stretch of the DNA to malfunction.  But if you inherited a good copy from your other parent, then lucky you, you're healthy (although you can still pass your "hidden" faulty copy on to your children).

This, incidentally, is why inbreeding -- both parents coming from the same genetic stock -- is a bad idea.  It doesn't cause problems in brain development, which a lot of people used to think.  But what it does mean is that if both parents have a recent common ancestor, the faulty genes one of them carries are very likely the same ones the other does, and the offspring has a higher chance of inheriting both damaged copies and thus showing the effects of the loss of function.  It's this mechanism that explains why a lot of human recessive genetic disorders are characteristic of particular ethnic groups, such as cystic fibrosis in northern Europeans, Tay-Sachs disease in Ashkenazic Jews, and malignant hyperthermia in French Canadians.  It only shows up in the children when both parents are from the same heritage -- which is why "miscegenation laws," preventing intermarriage between people of different races or ethnic backgrounds, are exactly backwards.  Mixed-race children are actually less likely to suffer from recessive genetic disorders -- the mom and dad each had their own "genetic load" of faulty genes, but there was no overlap between the two sets of errors.  Result: healthy kid.

So, how do asexual species get away with it?

Some of them -- like many bacteria -- just do a copy-and-paste job and create multiple copies of important genes.  That way, if Muller's ratchet knocks out one copy, they still have backups.  But I learned about another method, one I didn't know about, from an alert reader, who asked me if I'd ever heard of bdelloid rotifers -- which I had, although not much more than the name.  They're little microscopic animals that live in freshwater ponds, and seem entirely unremarkable.

Turns out they're extremely remarkable.

Scanning electron micrograph of bdelloid rotifers, along with close-ups of their jaws [Image licensed under the Creative Commons Diego Fontaneto, Bdelloid, CC BY 2.5]

The first new thing I learned was recent research has shown that rotifers are a paraphyletic group -- they don't form a clade, i.e. a group containing all the descendants of a particular branch point on the tree of life.  What used to be Phylum Rotifera has been rearranged because the thorny-headed worms -- formerly Phylum Acanthocephala -- were found through genetic studies to be more closely related to bdelloids than the bdelloids are to other rotifers, so either you'd have to lump the acanthocephalans in with the rotifers, or else split the entire group up.  Taxonomists mostly are leaning toward the former, creating a new Phylum Syndermata which contains all the rotifers and the spiny-headed worms.

But the bdelloids have another feature that's flat-out weird.  The species in this entire group are made up only of females, and they're parthenogenetic -- producing offspring without sexual reproduction.  There has never been a male bdelloid observed in nature.  So how do they not end up getting clobbered by the genetic Game of Telephone that is Muller's ratchet?

Turns out they get away with it by swiping genes from other organisms -- including not only other rotifers, but bacteria, fungi, and even plants!

Called horizontal gene transfer, this is something that is pretty routine in bacteria, but almost unheard of in animals.  Here's a quote from the paper by Evgeniy Gladyshev (of Harvard University) et al. I linked above, that first documented this.  Gladyshev sounds as astonished as the rest of us, doesn't he?

Horizontal gene transfer in metazoans has been documented in only a few species and is usually associated with endosymbiosis or parasitism.  By contrast, in bdelloid rotifers we found many genes that appear to have originated in bacteria, fungi, and plants, concentrated in telomeric regions along with diverse mobile genetic elements.  Bdelloid proximal gene-rich regions, however, appeared to lack foreign genes, thereby resembling those of model metazoan organisms.  Some of the foreign genes were defective, whereas others were intact and transcribed; some of the latter contained functional spliceosomal introns.  One such gene, apparently of bacterial origin, was overexpressed in Escherichia coli and yielded an active enzyme.  The capture and functional assimilation of exogenous genes may represent an important force in bdelloid evolution.

What shocks me most about this is how the hell this doesn't muck things up further.  I mean, it's a little like finding some typos in a book you're reading, and trying to solve the problem by tearing pages out of other books and inserting them into your book in random places.  Okay, maybe you now have fewer overall typos in the book than you did before, but what's the chance you picked up something you can actually use?

Apparently this point is still being studied.

So a peculiar little pond creature somehow makes no-boys-allowed parthenogenesis work by pilfering genes from all and sundry.  Which I have to admit is ingenious, but it's also just strange.  Darwin didn't know how right he was when he talked about "many forms most beautiful and most wonderful."  Can you imagine how gobsmacked he'd be if he could see what we know about biology today?

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It's a bird! It's a plane! No...

Thanks to my friend, the ever-sharp-eyed author Gil Miller, I now have a giant bruise in the middle of my forehead from doing facepalms.

Gil's contribution to my ongoing struggle against brain damage came about because of a website called The Living Sky, wherein we're told that there is a "new scientific answer to the mystery of UFOs."  Naturally eager to find out what this "scientific answer" might be, I started poking around the site, figuring I'd find that despite the word "new," it'd turn out to be the usual stuff about alien visitations and spaceships and faster-than-light travel.

Nope.

UFOs, we are told, aren't super-high-tech crafts that have crossed interstellar space to visit a planet that, frankly, more resembles a cosmic lunatic asylum than anywhere I'd want to visit.  UFOs aren't, in fact, crafts of any kind.

They're...

... lord have mercy, I'm having a hard time even writing this...

... they're sky jellyfish.

Well, that is new, I have to admit.

I wish I was making this up.  But wait... they have proof!  Here it is:

Welp, I dunno about you, but I'm convinced.

Oh, but not all of them are sky jellyfish.  Some of them are flying squid.

The... um, logic... goes something like this.

Marine invertebrates are some of the most common life forms on Earth.  They come in all shapes and sizes, and are "ideally suited to move in a fluid habitat."  Which, I think we can all agree, is lucky for them.

Many marine invertebrates have appendages like flaps, tentacles, and tails.  Some are bioluminescent.  Some are venomous, and encounters with them can cause injury or (in extreme cases) death.

The atmosphere is sometimes called "an ocean of air."

Okay, how about UFOs?

UFOs have been spotted in all shapes and sizes, move around quickly, and often have lights and what appear to be appendages.  Some people who have had close encounters with UFOs have sustained injuries.  The parallels are obvious

Also, one mustn't forget that crop circles are circular (as advertised), as are jellyfish.

So q.e.d., as far as I can see.

I should also mention that the site includes pages about "aerobiology" and "aerial plankton."

The whole thing reminded me (rather reluctantly) of the first episode of the first season of Star Trek: The Next Generation, "Encounter at Farpoint."  I have to admit it had its moments -- notably, introducing John de Lancie as Q -- but the downside was the rather ridiculous premise of a base on a planet that turned out to be an unlimited energy source because it was actually alive.  When Jean-Luc Picard et al. figure this out, and stop the evil base administrator from taking advantage of the creature's powers, it lifts off, and reveals itself as...

... you guessed it...

a Sky Jellyfish.

Me, I thought this was fiction, but what the hell do I know.

What strikes me about all this is that apparently the Living Sky people took a look at the aliens-and-spaceships claims, and said, "Nope.  That's not nearly loony enough.  Let's jettison the whole idea of technology entirely, and blame the whole phenomenon on flying squid."

I dunno, dude.  I've yet to see a crazy idea that becomes more plausible when you add stuff to it that makes it even crazier.

Anyhow, that's our dip into the deep end for today.  Just keep yourself alert, okay?  If you see any suspicious tentacles coming out of the sky toward you, seek shelter immediately.  I hear those things can pack a nasty sting.

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