Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Friday, April 19, 2024

The titan

One thing science teaches us is that just about everything is interesting if you look at it carefully enough.  Still, there's an ingrained human tendency to be overawed by superlatives -- the biggest, the heaviest, the brightest, the strongest, the most powerful.

It's why a recent fossil discovery from Somerset, England has made the headlines.  The rocks in Somerset, in the southwest of England, are mostly of Triassic age; it's not far from the famous "Jurassic Coast," which begins around Exmouth with Triassic sedimentary rocks that gradually become younger as you head west.  It's the site that the brilliant nineteenth century paleontologist Mary Anning studied -- becoming one of a very long list of talented women scientists who struggled for recognition by their male peers with tragically little success.

Somerset, which is a bit north from there, is also a great site for Mesozoic fossils, and some amateur fossil hunters recently found a doozy.  Father-and-daughter team Justin and Ruby Reynolds were searching along the north Somerset coast and saw what turned out to be a fossilized jawbone...

... of a creature which is estimated to have been twenty-five meters long.  (For my fellow Americans, twenty-five meters is about 130 bananas long.)

The animal was a type of ichthyosaur, a group that reached their height of diversity in the late Triassic Period.  We've known for a long time that ichthyosaurs were bizarre animals.  They were streamlined predators that look remarkably like dolphins, although they are only distantly related (making the two groups a great example of convergent evolution).  A number of them had an even stranger feature, which is the largest eye-diameter-to-body-size ratio of any animal known -- the well-named Ophthalmosaurus (Greek for "eye lizard") was six meters long and had eyes the size of basketballs.

But this new species could have eaten an Ophthalmosaurus as an appetizer and still had plenty of room for the entrée.  It's been dubbed Ichthyotitan severnensis -- more or less, "gigantic fish-thing from the Severn."  The fossil dates to about 202 million years ago.

[Image credit: artist Sergey Krasovskiy]

"I was highly impressed that Ruby and Justin correctly identified the discovery as another enormous jawbone from an ichthyosaur," said Dean Lomax, paleontologist at the University of Manchester, who verified the find and helped to classify it, in an interview with Science Daily.  "They recognized that it matched the one we described in 2018. I asked them whether they would like to join my team to study and describe this fossil, including naming it.  They jumped at the chance.  For Ruby, especially, she is now a published scientist who not only found but also helped to name a type of gigantic prehistoric reptile.  There are probably not many fifteen-year-olds who can say that!  A Mary Anning in the making, perhaps."

The Ichthyotitan, though, was one of the last of its kind; it, and a great many other species, were victims of the Late Triassic Mass Extinction, a poorly-understood extinction event that occurred around 201 million years ago and was only slightly smaller than the much better-known Cretaceous-Tertiary Extinction that would happen 135 million years later.  The most likely explanation of the Late Triassic event is volcanism and outgassing from the Central Atlantic Magmatic Province, the mantle upwelling from which would ultimately split up Pangaea and open the Atlantic Ocean, but that point is still being argued over by geologists and paleontologists.

Whether this particular Ichthyotitan was killed during the extinction event itself is, of course, impossible to tell, but the fossil dates to almost exactly the right time.  Its discovery also ramps up the search for more fossils along the north Somerset coast.  "It is quite remarkable to think that gigantic, blue whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period," Lomax said.  "These jawbones provide tantalizing evidence that perhaps one day a complete skull or skeleton of one of these giants might be found.  You never know."

It's a hell of a find -- a bone from a creature in contention for the largest animal known.  I don't know about you, but it's hard even to imagine a predator that big.  The late Triassic must have been an impressive-looking place...

... observed, of course, from a safe distance.

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Thursday, April 18, 2024

Flat space, Hawking radiation, and warm spots

Ever wonder if the universe is flat?

No, I haven't taken Wingnut Pills and decided that the Flat Earthers make sense.  This is an honest-to-Einstein problem in physics, one that not only raises eyebrows about the supposed "fine-tuning" of the universe but has a huge effect on its ultimate fate.

By this time most people who are reasonably scientifically literate (or at least watch Star Trek) know about curved space -- that the presence of mass warps space-time, a little like the way a heavy weight on a trampoline stretches and deforms the flexible sheet it's sitting on.  The trampoline analogy isn't a bad one; if you have a bowling ball in the middle of a trampoline, and you roll a marble on the surface, the marble's path will be deflected in such a way that it appears the bowling ball is attracting the marble.  In reality, however, there's no attraction involved; the bowling ball has warped the space around it, and the marble is only following the contours of the space it's traveling through.

Bump up the number of dimensions by one, and you've got an idea of how curved space-time works.  The trampoline is a 2-D surface warped into a third dimension; where you're sitting right now is a 3-D space warped into a fourth dimension.  (In fact, the effects of that curvature are what you are experiencing as a downward pull toward the Earth's surface right now.)

The "flatness problem" asks a seemingly simple question; okay, matter deforms space locally, but what's the shape of space as a whole?  In our trampoline analogy, you can visualize that although the bowling ball deflects the surface near it, as a whole the trampoline is flat.  Harder to picture, perhaps, is that the trampoline could be a different shape; the surface of the entire trampoline could be spherical, for example, and still have indentations on the surface corresponding to places where massive objects are located.

That, in a nutshell, is the flatness problem.  The key is the matter/energy density of the entire universe.  If the universe is flat as a whole, the matter/energy density is exactly right for the outward expansion from the Big Bang to slow down, asymptotically approaching zero, but never quite getting there (and never reversing direction).  A universe with a higher matter/energy density than the critical value would eventually halt, then fall inward again, resulting in a "Big Crunch" as all the stuff in the universe collapses back to a singularity.  (This is sometimes called a "spherical universe" because space-time would be warped into a four-dimensional hypersphere.  If you can't picture this, don't worry, neither can anyone else.)  If the matter/energy density is lower than the critical value, the universe would continue to expand forever, getting thinner and more spread out, eventually reaching the point where any particular cubic light year of space would have very little chance of having even a single atom in it somewhere.  (This is known as a "hyperbolic universe," for analogous reasons to the "spherical universe" mentioned above, but even harder to visualize.)
[Image is in the Public Domain courtesy of NASA]

So, which is it?

There doesn't seem to be a good reason, argued from first principles, that the universe has to be any particular one of the three.  When I first ran into this concept, in high school physics class, I was rooting for the spherical universe solution; ending the universe with an enormous collapse seemed (and still seems) preferable to the gradual attenuation of matter and energy that would occur with the other two.  Plus, it also raised the possibility of a rebounding second Big Bang and a new start, which was kind of hopeful-sounding even if nothing much would survive intact through the cusp.

Because there seemed to be no reason to expect the value of the matter-energy density -- known to physicists as Ω -- to be constrained, figuring out what it actually is occupied a great deal of time and effort by the astrophysicists.  It was a matter of some shock when by their best measurements, the value of Ω was:

1.00000000000000000000000000000000000000000000000000000000000000

To save you the trouble, that's exactly one, out to the 62nd decimal place.

So in other words, the universe is flat, or so close to it that we can't tell the difference.

This engenders more than a few other problems.  For one thing, why is Ω exactly 1?  Like I said earlier, nothing from the basic laws of physics seems to require it.  This brings up the issue of cosmological fine-tuning, which understandably makes us science-types a little twitchy.  Then there's the problem that the outer reaches of the universe that we can see -- so places farther away in space, and further back in time -- are moving away from us a lot faster than they should if the universe was flat.  This has given rise to a hypothesized repulsive "dark energy" to account for this, but what exactly dark energy is turns out to be even more problematic than the "dark matter" that appears to comprise over a quarter of the overall mass/energy of the universe even though we haven't been able to detect it other than by its gravitational bending of space-time.

The reason this warped topic comes up is research by the groundbreaking and often controversial Nobel laureate Roger Penrose, who published a paper in Monthly Notices of the Royal Astronomical Society that identified six "warm spots" that had been detected in the background radiation of the universe, and which Penrose believes are "Hawking points" -- places where a black hole evaporated due to its "Hawking radiation" eventually bleeding off mass (a topic I dealt with in a little more detail last year).  The problem is, the evaporation of a black hole by Hawking radiation generates theoretical lifetimes for your average black hole of many times the current age of the universe, so the presence of six of them indicates something funny must be going on.

What that funny business is, Penrose claims, is that we're seeing the ghosts of black holes that evaporated before the Big Bang that formed our universe.

In other words, in a previous universe.

"The Big Bang was not the beginning," Penrose said in an interview with Sarah Knapton in The Telegraph.  "There was something before the Big Bang and that something is what we will have in our future.  We have a universe that expands and expands, and all mass decays away, and in this crazy theory of mine, that remote future becomes the Big Bang of another aeon.  So our Big Bang began with something which was the remote future of a previous aeon."

So he's not talking about a spherical universe, collapsing in on itself; Penrose thinks that even if the universe is flat or hyperbolic, eventually random quantum fluctuations will generate an expansion that will start it all over again.  This may seem a little like the example my thermodynamics teacher used about random motion -- yes, it's possible that all the molecules in your cup of coffee will by chance jitter in the same direction at the same time, and your coffee will fountain up out of the cup.  He had us calculate the odds, though, and it turns out it's so remote that it's virtually certain it has never happened anywhere in the universe, during its entire thirteen-odd billion year existence.

But if you consider that a flat universe would have an essentially infinitely long time span, all it takes is the coffee to jitter in the right direction once, and you generate a new Big Bang.

Metaphorically speaking.

Whether Penrose is right about this remains to be seen, but it must be pointed out that he's had ideas before that have seemed "out there" and have turned out to be correct.  Martin Rees, Astronomer Royal and Fellow of Trinity College at the University of Cambridge and no faint light himself, said, "There would, I think, be a consensus that Penrose and Hawking are the two individuals who have done more than anyone else since Einstein to deepen our knowledge of gravity."

So I'm disinclined to shrug my shoulders at anything Penrose says, however odd it may sound.  And it brings me back to the hopes for an oscillating universe I first held when I was seventeen years old.  If Penrose is right, there was something that existed before our current universe, and likely something will exist afterward.  Even if those are in the impossibly remote past and future, it still seems preferable to the miserable demise of a standard flat or hyperbolic universe.

So the issue is far from settled.  Which is the way of science, after all.  Every problem you solve brings up two more new ones.  Meaning we should have enough to keep us occupied until the next Big Bang -- and maybe even beyond.

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Wednesday, April 17, 2024

The sound of thunder

Last Sunday (April 14) we had a series of thunderstorms roll through the region, kind of unusual for upstate New York at this time of year.  We're not particularly stormy in general, but most of the thunder and lightning we do get comes in the heat of midsummer.  On Sunday, though, a warm front brought in turbulent, moist air, and we got some decent storms and rain for most of the day.

At 11:51 AM (EDT), though, something odd happened.  There was a deep, shuddering rumble that repeated three times within the span of about two or three minutes.  (The first was the strongest.)  I grew up in the Deep South, where thunder is a frequent occurrence, and to my ears this didn't feel or sound like thunder.  Immediately I thought of a mild earthquake -- primed, of course, by the April 6 quake, centered in New Jersey, which was felt over large regions of New York and the neighboring states.

The rumble we experienced preceded the arrival of the strongest of the storms; because of that, and the fact that it "sounded wrong," I was convinced that we'd experienced an earthquake.  That conviction intensified when reports began to pour in that the same noise had been heard at the same time -- in locations separated by fifty kilometers or more.  (Thunder ordinarily can only be heard about fifteen kilometers from the source.)  

My wife, on the other hand, was absolutely sure it was thunder, albeit rather powerful and deep-pitched.

Well, let it never be said that I won't admit it when I'm wrong.


I started to doubt myself when the Paleontological Research Institution in Ithaca (only ten miles from my home) reported on Monday morning that despite numerous people calling in to report noise and shaking, their seismometer had not recorded an earthquake.  That seemed pretty unequivocal -- and after all, there had been storms in the area, even though at the time we heard the rumble, the center of the front wouldn't arrive for over an hour.  But if it had been thunder, how had a single thunderclap (or three in rapid succession) been heard over such a great distance?

The answer turns out to be a temperature inversion.  Ordinarily, temperature decreases as you go up in altitude; but this effect competes with the fact that cool air is denser and tends to sink.  (This is why in winter, the greatest risk of frost damage to plants is in isolated valleys.)  So sometimes, a wedge of warm air gets forced up and over a blob of cooler air, meaning that for a while, the temperature rises as you go up in altitude.

This is exactly what happens in a warm front; the warm air, which carries more moisture, rises and forms clouds (and if there's enough moisture and a high enough temperature gradient, thunderclouds).  But this has another effect that is less well known -- at least, by me.

The difference in density of warm and cool air means that they have different indices of refraction -- a measure of how fast a wave can travel in the medium.  A common example of different indices of refraction is the bending of light at the boundary between air and water, which is why a pencil leaning in a glass of water looks kinked at the boundary.  At a shallow enough angle, the wave doesn't cross the boundary at all, but reflects off the surface layer; this causes the heat shimmer you see on hot road surfaces, as light bounces off the layer of hot air right above the asphalt.

Sound waves can also refract, although the effect is less obvious.  But that's exactly what happened on Sunday.  A powerful lightning strike created a roll of thunder, and the sound waves propagated outward at about 343 meters per second; but when they struck the undersurface of the temperature inversion, instead of dispersing upward into the upper atmosphere, they reflected back downward.  This not only drastically increased the distance over which the sound was heard, but amplified it, changing the quality of the sound from the usual booming roll we associate with thunder to something more like an explosion -- or an earthquake.

So despite the jolt and the odd (and startlingly loud) sound, we didn't have an earthquake on Sunday.  I'm kind of disappointed, actually.  I didn't feel the one on April 6 -- although some folks in the area did -- and despite having lived in a tectonically-active part of the country (Seattle, Washington) for ten years, I've never experienced an earthquake.  I'd rather not have my house fall down, or anything, but given that the pinnacle of excitement around here is when the farmer across the road bales his hay, a mild jolt would have been kind of entertaining.

But I guess I can't check that box quite yet.  Thunder, combined with a temperature inversion, was all it was.

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Tuesday, April 16, 2024

Dream songs

Last night I dreamed that our local mall had been converted into a giant used book store.  (Something I would entirely approve of.)  We were going to to go shopping ("we" being my wife, me, and our younger son, who lives in Houston but was apparently up for a visit) but we realized that a bunch of other family members were unexpectedly going to descend upon us, and for some reason we knew they were going to walk into our house without knocking, which our dogs would not appreciate, so we had to get home fast.  But while trying to get out of the mall we were hindered by a bunch of science-fiction cosplayers wearing silver body paint.

After that, it got kind of weird.

Dreams are a very peculiar thing, but they (and the REM sleep stage during which they occur) are ubiquitous in the brainier species of animals.  In fact, as I'm writing this, my puppy Jethro is curled up in his bed by my desk dreaming about something, because his paws are twitching and every once in a while he makes a very cute little "oof" noise.  But what would a puppy dream about?  Presumably the things that make up his waking life -- playing, chasing squirrels, swimming in our pond, eating his dinner.

You have to wonder if sometimes dogs, like humans, have weird dreams, and what they might make of them.

The function of dreaming is unknown, but what's certain is that it's necessary.  Suppress REM and dreaming, and the results are hallucinations and psychosis.  Aficionados of Star Trek: The Next Generation will no doubt remember the chilling scene in the episode "Night Terrors," where something is preventing the crew from experiencing REM sleep, and Dr. Crusher is in the makeshift morgue where the victims of a massacre are being examined -- and when she turns around, all the dead bodies are sitting up, still shrouded in their sheets.  She closes her eyes -- exhibiting far more bravery than I would have -- and says, "This is not real," and when she opens them, they're all lying back down again.

*shudder*

In any case, what brings up this topic today is far cheerier; a fascinating piece of research out of the University of Buenos Aires that looked at dreams in an animal we usually don't associate with them -- birds.  A team led by Gabriel Mindlin looked at a species of bird called the Great Kiskadee (Pitangus sulphuratus), a brightly-colored and vocal flycatcher found in much of Central and South America.  


Mindlin is one of the foremost experts in the physiology of bird song.  Birds have a unique apparatus called the syrinx that allows them to make some of the most complex vocalizations of any group of animals; not only can some (such as many wrens and thrushes) produce two or more tones at the same time, birds like parrots, mynahs, lyrebirds, and starlings are brilliant mimics and can imitate a variety of other sounds, including human speech.  (A lyrebird in a park in Australia learned to convincingly imitate a chainsaw, a car alarm, various cellphone ringtones, and a camera shutter.)


What Mindlin and his team did was to implant electrodes in the obliquus ventralis muscle, the main muscle birds use to control pitch and volume in vocalization, and also outfit some Great Kiskadees with devices to monitor their brain waves.  When the birds went into REM sleep, the researchers found that the OV muscle was contracting in exactly the way it does when the birds vocalize while awake.

The birds were singing silently in their sleep!

Singing in birds generally serves two purposes; mate attraction and territorial defense.  (As one of my AP Biology students put it, "they sing when they're mad or horny.")  It's more complicated than that -- science generally is -- but as a broad-brush explanation, it'll do.  Many species have different songs and calls for different purposes, each associated with a specific pattern of contractions and relaxation of the muscles in the syrinx.  Mindlin and his team used software capable of taking the muscle movements the electrodes detected and decoding them, determining what song the bird would have been producing if it was awake.  What they found was that the song their test subjects were dream-singing was one associated with marking out territories. 

"I felt great empathy imagining that solitary bird recreating a territorial dispute in its dream," Mindlin said.  "We have more in common with other species that we usually recognize."

So birds dream, and the content of their dreams is apparently -- just like Jethro -- taken from their own umwelt, the slice of sensory experience they engage with while they're awake.  (I wrote in more detail about the umwelt a while back, if you're curious.)  

On the other hand, how this accounts for my dream of silver-body-painted cosplayers in a mall filled with old books, I have no idea.

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Monday, April 15, 2024

Stellar wind, the BOAT, and the Dragon's Egg

Since the news down here on Earth is not looking so good, today we're going to escape to my happy place, which is outer space.

We've got three new studies of fascinating astronomical phenomena to look at, the first of which comes out of the University of Vienna.  A team led by astrophysicist Kristina Kislyakova has, for the first time, directly detected stellar wind from three nearby Sun-like stars -- something which may effect the stability of the atmospheres of any planets orbiting them, and thus, their potential habitability.

Stellar wind -- which until now, we only knew about from studies of our own solar wind -- is a stream of particles given off by the upper atmosphere of stars, mainly composed of electrons, protons, and alpha particles with a kinetic energy of under 10 keV.  The solar wind is why comet tails always point away from the Sun (not, as many people erroneously think, simply the opposite of their direction of motion, like the wake of a boat).  Kislyakova's team looked for x-rays of specific frequencies coming from the three stars they studied (70 Ophiuchi, Epsilon Eridani, and 61 Cygni), because the stellar wind is expected also to contain small amounts of ionized oxygen, nitrogen, and carbon; as those ions are blown from the surface of the stars and ultimately slow down, they capture electrons, which drop into the atom's ground state and emit electromagnetic energy in the form of x-rays at particular frequencies.  From the amount of x-rays detected, they estimated the mass loss rate of the stars.

All three have much stronger stellar winds than the Sun does -- around 66, 16, and 10 (respectively) times the rate of mass loss from solar wind that the Sun experiences, which is itself considerable (estimated at 1.5 million metric tons per second).  The reason for the higher mass loss from the three stars studied is unknown -- but the Sun's calmer behavior is a good thing, because a strong stellar wind can peel away the atmosphere of exoplanets.  Any planets around 70 Ophiuchi, for example, are likely not to have much in the way of an atmosphere.

The second study is out of Northwestern University, and looked at something that has been nicknamed the BOAT (brightest of all time) -- a gamma-ray burst picked up in October of 2022 that saturated every gamma-ray detector on Earth.  It came from a source about 2.4 billion light years away in the constellation of Sagitta, and lasted for a few hundred seconds before starting to fade.  During that time it outshone the next-brightest observed gamma-ray burst by a factor of ten.

A team led by astrophysicist Peter Blanchard found that the BOAT was caused by a supernova -- but one acting very strangely.  The gamma-ray burst was so powerful that it took scientists some time to figure out that there even had been a supernova (imagine something so bright that it hides the light coming from a supernova!).  "The GRB was so bright that it obscured any potential supernova signature in the first weeks and months after the burst," Blanchard said.  "At these times, the so-called afterglow of the GRB was like the headlights of a car coming straight at you, preventing you from seeing the car itself.  So, we had to wait for it to fade significantly to give us a chance of seeing the supernova."

So why would an ordinary (if you can use that word) supernova cause such an enormous gamma-ray burst?  One possibility is that we might just be at the right place at the right time.  Models indicate that a rapidly-spinning massive star, when it reaches the end of its life, collapses into a black hole that gives off a a narrow jet of gamma rays aligned with the axis of its rotation.  It's possible that we just happened to be perfectly lined up with the black hole's axis -- looking right down the gun barrel, as it were.  But the fact is, they're still trying to figure that out, so we'll have to wait to see what more they learn.

The third study, led by astrophysicist Abigail Frost of the European Southern Observatory in Chile, looked at a strange and beautiful object nicknamed the "Dragon's Egg," in the southern constellation of Norma.

[Image credit: European Southern Observatory's Paranal Observatory in Cerro Paranal, Chile. ESO/VPHAS+/CASU/]

The curious thing about the pair of stars in the middle of the Dragon's Egg is that one of them has a magnetic field and the other doesn't.  Frost and her team believe that the same process that created the nebula surrounding them is what created the magnetic field in one of the stars.

It seems to be a case of stellar fratricide.  The more massive star in the binary pair is the one with the magnetic field, and the theory is that it used to be a triple star system -- but two of the stars underwent a merger.  The violence of that collision blew material out into space (the origin of the glowing dust cloud surrounding the remaining two stars) -- and the result dramatically increased the spin rate of the combined star, a bit like water speeding up as it goes down a drain.  Electrically-charged particles, such as those in stellar atmospheres, traveling in circles generate a magnetic field as per Maxwell's Laws, and that's why the more massive member of the surviving binary has such a powerful field.

So that's today's exploration of astronomical news.  Always makes me feel a bit tiny, when I consider phenomena out there in the depths of outer space.  Nothing wrong with that, of course -- humility is good.  And all in all, I'd rather be looking up than looking down in any case.

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Saturday, April 13, 2024

The stowaways

Aficionados of the Star Trek universe undoubtedly recall the iconic character Jadzia Dax.  Dax was a Trill -- a fusion of a humanoid host and a strange-looking brain symbiont.  The union of the two blended their personalities, resulting in what was truly a new, composite life form.


Star Trek is amazing in a lot of ways, not least because of their attention to current science and an uncanny prescience about where science is heading.  It turns out that we're all composite life forms.  We carry around something like 39 trillion bacterial cells in and on our own bodies -- the vast majority of which are either commensals (neither helpful nor harmful) or are actually beneficial -- a number that is higher than the number of human cells we have.  Each of our cells also contains mitochondria, which are the descendants of endosymbiotic bacteria that have inhabited the cells of eukaryotes for billions of years, and without which we couldn't release energy from our food molecules.  Plants have not only mitochondria but chloroplasts, yet another species of bacteria that like mitochondria, have their own DNA, took up residence in their hosts billions of years ago, and have been there ever since.

But the rabbit hole goes a hell of a lot deeper than that.  By some estimates, between five and eight percent of our genomes are endogenous retroviruses -- genetic fragments left behind by viruses that spliced their DNA into ours.  Like our bacterial hitchhikers, a good many of these are either neutral or beneficial; for example, the production of bile, estrogen, and several proteins essential for the formation of the placenta are all directly affected by endogenous retroviral genes.  A few do seem to be deleterious, and have roles in certain cancers, autoimmune diseases, and neurological disorders like ALS and schizophrenia.

What brings this topic up is an astonishing study led by Tyler Coale, of the University of California - Santa Cruz, that came out in the journal Science this week.  Coale's study found there's yet another example of endosymbiosis -- this one a lot more recently evolved -- which turned a formerly free-living nitrogen-fixing bacterium into a true cellular organelle.

Nitrogen is critical for the production of both proteins and DNA.  Although 78% of the air we breathe is nitrogen, it's completely useless to us; we breathe it right back out.  All the nitrogen in our bodies' proteins and nucleic acids had to pass through a food chain that started with nitrogen-fixing bacteria, the only known organisms that can absorb nitrogen from the air and convert it to an organic compound.  Leguminous plants like beans, peas, alfalfa, and clover have a nifty symbiotic arrangement with nitrogen-fixing bacteria; they create nodules in their roots where the bacteria live, and the bacteria provide the plants with a ready source of nitrogen.

But in legumes, the two remain independent organisms.  What Coale and his colleague discovered is a species of algae (Braarudosphaera bigelowii) in which the bacteria (UCYN-A) have evolved to become inseparable from the host cells.  In other words, they became an organelle, just like mitochondria and chloroplasts.

Although there's no canonical definition of organelle, most biologists include two must-haves: (1) coordinated division of the organelle within the cell; and (2) the evolution of a transport system that allows for specific tagging and importation of proteins into the organelle.  By those standards, UCYN-A is definitely an organelle.  

"Both boxes are checked by Coale," said Jeff Elhai, microbiologist at Virginia Commonwealth University.  "Even to the semantic purists, UCYN-A must be counted as an organelle, joining mitochondria, chloroplasts and chromatophores."

All these stowaways, in the cells of just about every living thing on Earth, call into question what exactly we mean not only by the word organelle but by the word organism.  The high-school-biology-class definition of an organism is "an individual life form of a species."  But is there any such thing?  The ostensibly individual life form called Gordon who is currently writing this post is made of (at least) equal numbers of human cells and cells from different species of bacteria, without many of which I'd be sick as hell, or possibly even dead.  Remove the symbiotic mitochondria from within my cells, and I'd definitely be dead -- within minutes.  Deeper still, at a minimum, one in twenty of the genes in my "human DNA" comes from viruses and bacteria.

Looked at closely, I'm as put together of spare parts as the Junk Man in Lost in Space.  Fortunately, I appear to run a bit more smoothly most days than he did.


In any case, calling me "a single organism" is so far from accurate it's almost laughable.

Honestly, it's kind of cool how interconnected everything is.  Back in the days of the first serious taxonomist, Swedish biologist Carl Linnaeus, scientists had the idea that all living things were categorizable into neat little cubbyholes.  Not only is that incorrect on the species level (something I wrote about in detail a couple of years ago), it's not even true on the individual level or on the level of genomes.  Life on Earth is a huge, tangled skein of threads.  The whole thing puts me in mind of a quote from John Muir: "Tug at a single thing in nature, and you find that it is hitched to everything else in the universe."

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Friday, April 12, 2024

The kakistocracy

Today I'd like to look at the state of Arizona, where this week a 4-2 decision by the state's Supreme Court made abortions illegal in any circumstance except to save a woman's life -- practically speaking, making them illegal period, because few doctors will want to risk their livelihood (or their freedom) based on whether a court will decide a particular abortion was a medical necessity.

This decision caused the state law to revert to a code passed in 1864 -- decades before women even had the right to vote.  It's an interesting historical filigree that the man who pushed the 1864 law through in the first place, then Speaker of the House for the Arizona Territory W. Claude Jones, was a notorious adulterer, philanderer, liar, and pedophile (he openly called himself a "pursuer of nubile females"), whose victims included a twelve-year old Mexican girl and a fifteen-year-old who had recently arrived with her parents from Texas.  The decision by the court is also irrespective of the fact that such restrictions are wildly unpopular; in a 2023 poll, only thirteen percent of Americans responded that abortion should be illegal in all circumstances, and just over sixty percent stated that the United States Supreme Court's Dobbs decision (which overturned Roe v. Wade) was "a bad thing."

What's striking about this is that despite the fact that the majority of American citizens are at least pro-choice in some circumstances, they keep electing people who are somewhere to the right of Tomás de Torquemada.  Take, for example, Arizona State Senator Anthony Kern, who crowed, "Looks like our prayer team stirred up some God-haters," and led a prayer circle on the floor of the Senate in which -- I shit you not -- he "spoke in tongues."

Is it just me, or do these people sound like this?


A point I've made (many times) here in Skeptophilia is that I have no issue with what you believe, as long as you don't use those beliefs as a hammer to force others to comply.  On the other hand, I am under no obligation to refrain from saying those beliefs are ridiculous, especially when you make a point of exhibiting them in public.

Put another way: I always try to respect people, but ideas only deserve respect if they make sense and honor other people's rights.

A few days ago I saw a post on social media where a guy took exception to those of us who were making fun of Rapture-believers who thought the total eclipse on Monday was a sign of the End Times.  "Most Rapture-believers don't think that," he said (despite the fact that people like Marjorie Taylor Greene stated that the eclipse was a "sign from God to repent"), then sniffed, "People who are making fun of Rapture-believers are actually making fun of themselves."

Um, no.  We're actually making fun of the Rapture-believers.  If you hold silly beliefs, you can't blame other people for laughing.

The whole problem escalates when these people are elected to public office, and start using their bizarre worldviews to drive policy.  For example, a law in Louisiana just passed the House which would require all public school classrooms to post the Ten Commandments.  (And before you @ me about how the Ten Commandments are just guides to good behavior, and apply regardless of whether you're religious or not, allow me to remind you that the First Commandment is "I am the Lord thy God; you shall have no other gods before me.")  Another proposed bill in my former home state, HB777, would make it a criminal offense for a librarian to belong to the American Library Association -- because libraries have long stood for free access to information, which is absolutely anathema to the Far Right.  (Also because the ALA has championed the availability of books representing racial diversity and LGBTQ+ representation; apparently we can't have the world knowing there are people who aren't straight white Christians.)

I can only hope that Americans are becoming aware of the extent to which people who proudly espouse loony beliefs have taken control of the government, and that this will galvanize voters to turn out for the election this November.  I'm not talking about true conservatives (people like former congressman Joe Walsh) -- although I may not agree with him about all that much, I could have a reasonable discussion with him.  But I have zero common ground with irrational religious ideologues like current Speaker of the House Mike Johnson, and snarling hypocrites like Lauren Boebert, who publicly stated that she's all about "family values" and is "tired of this separation of church and state junk" but who apparently thinks it's A-OK to give her boyfriend a handjob in a public theater.

We have allowed ourselves to be controlled by a group of men and women whose outsized impact on our laws far exceeds their numbers.  We can turn this around -- but only if people get themselves to the polls.  We don't need elected officials like Anthony Kern babbling, "Ickety ackety ooh aah aah," then claiming those are God's words saying what a Very Good Boy He Is.  We need people capable of reasoned discourse, who -- even if they disagree -- can present their arguments based on facts and logic, not on some bizarre set of beliefs that make about as much sense as claiming that the universe is being controlled by a Giant Green Bunny From The Andromeda Galaxy.

Which means that we need to voteAll of us.  Our system is far from perfect, but this year the choice is stark.  (Maybe it always is.)  The Greeks had a word for the direction we're heading: a kakistocracy, government by the worst, the most unfit, or the most unscrupulous.  Remember the quote from Plato: "The price of apathy toward public affairs is to be ruled by those who are actively evil."

Or, in the case of Anthony Kern, flat-out insane.  

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