Raw nonsense

Despite the fact that our modern lifestyle has increased our life expectancy to longer than it's ever been in the history of humanity, romanticizing the practices of the past is still ridiculously widespread.

People who claim that "everything causes cancer" conveniently ignore two things: first, that a good many forms of cancer would decline dramatically if we'd do things doctors recommend, like cutting out tobacco and getting vaccinated against HPV; and second, that one of the reasons cancer rates have climbed is that we're no longer dying of other stuff, like diphtheria, typhoid, measles, and smallpox.

But that kind of thinking seldom makes any inroads into the minds of people committed to anti-vaxx (or completely anti-medical) propaganda.  The levels of irrationality some of this thinking reaches are truly staggering.  I had one person comment on one of my posts -- in all apparent seriousness -- "my great-grandma never got vaccinated against anything, and she survived."

Well, of course she did.  If she'd died at age three of diphtheria, she wouldn't have been your great-grandma, now would she?

How about asking great-grandma how many of her siblings and cousins died of childhood infectious diseases -- like my grandfather's two oldest sisters, Marie-Aimée and Anne-Désée, who died five days apart at the ages of 22 and 16 -- of measles.

The person who posted that comment should win some sort of award for compressing the greatest number of fallacies into the shortest possible space.  Confirmation bias, cherry-picking, anecdotal evidence, and the post hoc fallacy, all in nine words.  Kind of impressive, actually.

Despite all this, there are huge numbers of people who want to return to what our distant ancestors did, claiming that it's "healthier" or "more natural," conveniently neglecting the fact that back then, as Thomas Hobbes so trenchantly put it, "life was solitary, poor, nasty, brutish, and short."

The result is the kind of thing I ran into in an article in Ars Technica last week about a trend I hadn't heard of, which is to drink "raw water."  "Raw water," which you might guess from the name, is water that hasn't been filtered or treated, but is collected (or even bottled and sold) right from a spring or river or whatnot.  And predictably, what happened was that nineteen people fell ill with a diarrheal disease (specifically Campylobacter jejuni) when it turned out that their trendy "natural spring water" turned out to be just ordinary runoff from a creek drainage that had been contaminated by bacteria from bird nests.

The amount of pseudoscience you run into with this stuff is astonishing.  In researching this topic, I found people who claim that "industrially-processed water" (i.e. most tap water) has "mind-control drugs" in it, designed to turn us all into Koolaid-drinkin' sheeple, and even one that said treatment plants deliberately "alter the molecular structure of water, turning it into a toxin."

Making me wonder how, or if, these people passed high school chemistry.

I spent the summers during my twenties and thirties back-country camping in the Cascades and Olympics, and I know how careful you have to be.  The clearest bubbling mountain brook can be contaminated with nasty stuff like Giardia and Salmonella, two diseases that should be high on the list of germs you never want to have inside you.  I used iodine sterilizing tablets for all the water I drank -- and I never got sick.  But I knew people who did, and as one of them vividly described it, "Having Giardia means that for three weeks you're going to be on a first-name basis with your toilet."

Which is funny until you find out that in the process, he lost twenty pounds and spent three days in the hospital hooked up to an IV so he could stay hydrated.

Look, I know our high-tech world isn't perfect.  I know about pesticides and herbicides and industrial contamination and coverups and food additives with dubious health effects.  My wife and I try as hard as we can to eat locally-sourced organic meat and produce, not to mention growing our own vegetables.  But the admittedly true statement that technology and the pharmaceuticals industry have created some problems does not equate to "therefore we should jettison everything they provide and return to the Stone Age."

Speaking of fallacies, there's another one for you: the package-deal fallacy.  You get into this stuff, it reads like the "what not to do" section of a critical thinking textbook.

So if you're inclined to switch over to "raw water," just don't.  Drinking water is treated for a reason.  Our Stone Age ancestors didn't have such great lives, and idealizing it as some kind of idyllic Garden of Eden is complete horse shit. 

Horse shit ironically being one of the things that might well be in your "raw water."

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Mapping our world

My novel The Scattering Winds is the second of a trilogy, of which the first book (In the Midst of Lions) is scheduled to be out this summer.  The setting of the trilogy is the Pacific Northwest.  In the first book, there's a worldwide collapse of civilization.  In the second, set six hundred years later, what's left of humanity has reverted to a new Dark Ages, mostly non-literate and non-technological.  In the third (The Chains of the Pleiades), six hundred years after that, technology and space flight have been re-invented -- along with all the problems that brings.

The main character of the second book, Kallian Dorn, comes from a people have lost the knowledge of reading, committing all of their culture's memory to the mind of one person, called the Guardian of the Word.  But when they find a girl from a distant town, a refugee, who knows the rudiments of reading and writing, they recognize what's been lost, and struggle, slowly, to reclaim it.  Kallian undertakes a voyage, on foot, to the girl's home town -- and finds there a mostly-intact library from what he calls "the Before Times."

The following takes place when Kallian, who by this time has learned the basics of how to read, discovers a room full of maps in the library:

He went into the first room he encountered. It was labeled “Maps.”  Holding the lamp aloft, he passed into a room filled with odd cabinets, most of which had very wide, shallow drawers.  The nearest one said, “North America,” and he set the lamp down to open the top drawer.

Sitting on top was a yellowed piece of paper, about an arm’s length wide and tall, with a drawing of… what was it?  He peered closer, and read the inscription at the top, written in an ornate, curly script he could barely decipher.  It said, “United States of America, The Year of Our Lord 1882.”  There were names written in smaller, but equally frilly, lettering, and gave him enough information to conclude that it was a drawing of a land, as if seen from above.  The faded blue bits were bodies of water: Lake Ontario.  The Caribbean Sea.  The Atlantic Ocean.  The green parts—well, they were only green in splotches, mostly they had faded to a yellowish-brown—were land.  He saw features like “Appalachian Mountains” and “Great Plains” and “Mississippi Delta.”  The land was divided by oddly artificial-looking black lines, some dead straight, others following natural features such as the course of rivers.  Each of the blocks thus delineated had a strange and unfamiliar name: Massachusetts.  New York.  Georgia.  Kentucky.

Had these been kingdoms of the Before Time?

1882—if he was correct about what the date-numbers signified, this would have been about a century and a half before the collapse, before the floods and plagues that had ended the old world.  And a full 750 years before now.

But where was this United States of America, with its bizarrely-named mountains and lakes and kingdoms?  Without a referent, without having an arrow on the map saying “You are here,” he had no way to know if it was a day’s march away or on the other side of the world.

He flipped through the maps in those and other cabinets, handling them carefully to keep the age-worn paper from crumbling in his hands.  His mind was overwhelmed with how many different lands there were—whole cabinets devoted to maps from places called Europe, Africa, Asia, Australia.  But even looking at them, as fascinating as it was, was not like reading the books he’d found, where meaning provided an anchor to keep him fastened to reality as he knew it.  Without a key, the maps gave him no way to tell scale or location of anything.  Learning to read had unlocked one type of cipher; here was an entirely different kind, one where even though he could read the words, they didn’t make sense.

I was reminded of this scene when I read an article yesterday in Science News about archaeologists who believe they've discovered the oldest-ever aerial-view scale drawings -- in other words, maps.  There are structures in the Middle East nicknamed "kites" that were huge stone-walled enclosures used to trap animals like gazelles, funneling their movements toward waiting hunters.  And a team of archaeologists working in Jordan and Saudi Arabia have found nine-thousand-year-old engravings on stones that appear to be maps of nearby kites -- perhaps made by people strategizing how best to use them in their game-harvesting efforts.

Map-making, when you think about it, is kind of an amazing accomplishment.  It requires changing your perspective, picturing what some thing -- a city, a body of water, a country, an entire continent -- would look like from above.  And even if to our modern eyes, when we can see what things look like from the air, old maps look pretty inaccurate, it's important to remember that they did it all by surveying from ground (or sea) level.

And given that, they did pretty damn well, I think.

A map of the world, ca. 1565 [Image is in the Public Domain]

The fact that we were doing this nine thousand years ago is kind of astonishing.  Intrepid folks, our ancestors.

So many of the things we do today, and consider "modern," have far deeper roots than we realize.  And this ability to shift perspective, to consider what things would look like from another angle, is something we've had for a very long time -- even if to someone like Kallian Dorn, the results look very like magic.

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Not magic

Can I beg scientists to please please puhleeeez stop giving names to scientific phenomena that induce the woo-woos to have multiple orgasms?

It's bad enough that the woo-woos already take perfectly reasonable terms like "frequency" and "vibration" and "resonance" and "quantum" and define them any damn way they want, and interpret the Heisenberg Uncertainty Principle as meaning "we're not certain about anything, therefore my noodling around is just as likely to be true as whatever Stephen Hawking came up with."  But some of the names the scientists themselves have come up with are just egging the woo-woos on, with the same result as my putting a pair of juicy pork chops on the floor in front of my dogs and turning my back.

Then acting all surprised when 3.8 milliseconds later, there's nothing but contented chewing noises.

This sort of thing happens way too often.  I suspect that a lot of it has to do with an honest desire to give laypeople some sort of simple, catchy phrase to hang onto.  After all, a lot of physics -- and the problem does seem to occur most often in physics -- is hard and math-y, so the real models themselves are often relatively inaccessible to people who haven't been trained in the field.  (And even some who have.  Despite my bachelor's degree in physics, 95% of academic papers in physics lose me after the first paragraph.  If I even get that far.)

But for fuck's sake, let's learn from our mistakes, okay?  Look at what happened when Murray Gell-Mann introduced a new quantum characteristic, and dubbed it "strangeness."  There's nothing especially strange about strangeness, or at least, it's no stranger than the rest of the quantum model.  Actually, it's a number, and describes the decay of certain particles in strong nuclear and electromagnetic interactions.  But the name stuck, and the "strange quark" has gotten the woo-woos going, lo unto this very day.

There's no better example, however, than the infamous "God Particle."  This moniker was given to the Higgs boson by physicist Leon Lederman because of its ability to interact with and influence any particle with mass, but Lederman himself quickly realized what a misstep this was.  He later said he regretted not calling it the "goddamn particle," but admitted this probably wouldn't have gotten past his editors.

The whole annoying subject comes up because of an article this week in Phys.org about a new mathematical model that may account for the chaotic high energy and information loss that occurs near black holes.  The gravitational fields around a black hole's event horizon are so warped by the high mass that standard formulations tend to break down, and simulating them in a model has proven to be extremely complex.

[Image licensed under the Creative Commons Event Horizon Telescope, Black hole - Messier 87 crop max res, CC BY 4.0]

So Kanato Goto, Tomoki Nosaka, and Masahiro Nozaki, of RIKEN Interdisciplinary Theoretical and Mathematical Sciences, have come up with a new model to account for the complicated behavior at the boundary of a black hole.  It uses a mathematical measure of how difficult a quantum system is to simulate on a classical (non-quantum) computer.  Figuring it into their calculations, Goto et al. were able to show that near the boundary of a black hole, systems will evolve to maximize this measure -- i.e., to become maximally complex and chaotic.

So far, so good, right?  But I haven't told you what this mathematical measure is called.

It's called magic.

When I saw this, I said, and I quote, "Oh, fuck."

In fact, the Phys.org article is titled, "Quantum 'Magic' Could Help Explain the Origin of Spacetime."  At least they had the good sense to put Magic in quotation marks.

Not that it'll help.  I predict that there will be articles on woo-woo websites popping up all over the place claiming that scientists are finally admitting that the whole universe is magical.  Citing the headline, probably without the relevant quotation marks, and conveniently ignoring the contents of the actual article.  "See?  We were right!  It is all magic!  So crystals and homeopathy and astrology and quantum vibrations of love and everything else we've been babbling about for decades!"

Confirmation Bias "R" Us, baby. 

Anyhow, I guess anything I say isn't going to offset this trend to give purely scientific stuff goofy and/or eye-catching names.  But as far as quantum magic -- without the quotation marks -- goes, let me end this rant with a quote from the inimitable Tim Minchin: "Throughout history, every mystery ever solved has turned out to be... not magic."

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Likes attract

A bit over 23 years ago, a friend introduced me to a woman she'd known since they were toddlers together.  I was recovering from an unpleasant divorce, trying to adjust to being a single dad, and (honestly) was pretty lonely.  The friend told me we'd get along great -- mutual interests in music, birdwatching, gardening, and travel.

"Two such similar people should definitely get to know each other," she said.

Despite the fact that even on a good day, I raise social awkwardness to the level of performance art, I got up my gumption, called her up, and asked her out.  Sure enough, we hit it off brilliantly.  That summer, we went with some friends on a three-week trip to Iceland.  After a few more adventures big and small, we decided to make it permanent.  We're still together.

Carol and me in Cornwall in 2015

And our friend was right; we are really similar.  We nearly finish each other's sentences sometimes.  And I can't keep track of the number of times one of us has said something random, and the other has responded in shock, "I was just going to say that."

Some new research out of Boston University suggests a reason why the old adage of "opposites attract" might not be that accurate.  We're attracted to people who are like us, usually (at least at first) about one or two standout traits -- like birdwatching and gardening -- because of self-essentialist reasoning.  This is the idea that our core being is shaped by our passions and our dislikes, and when we find someone who resonates with us on some of those, we assume they'll share our other personality traits, as well.

That we'll be "soulmates."

"If we had to come up with an image of our sense of self, it would be this nugget, an almost magical core inside that emanates out and causes what we can see and observe about people and ourselves," said Charles Chu, who co-authored the study.  "We argue that believing people have an underlying essence allows us to assume or infer that when we see someone who shares a single characteristic, they must share my entire deeply rooted essence, as well."

The problem is, that thinking has a flaw.  You can share one or two deep connections, and still be different on a whole lot of other things, including some important ones -- maybe even some that are deal-breakers.  "We are all so complex," Chu said.  "But we only have full insight into our own thoughts and feelings, and the minds of others are often a mystery to us.  What this work suggests is that we often fill in the blanks of others' minds with our own sense of self and that can sometimes lead us into some unwarranted assumptions."

With Carol and me, for example, there's the still-baffling disconnect we have over books.  With a very few exceptions -- The Hitchhiker's Guide to the Galaxy is one, and the Discworld novels of Terry Pratchett -- I can nearly guarantee that if I love a book, she won't, and vice-versa.  Even with authors we both like (for example, Christopher Moore), we don't resonate with the same books.  She loved Fluke and I thought it was too weird and implausible, even by Moore's standards, to work; I found Coyote Blue brilliant and it's probably her least favorite of Moore's books.  (At least we agree on A Dirty Job and its sequel, Secondhand Souls, which are flat-out genius.)

Fortunately, the fact that Carol thinks my all-time favorite book, Umberto Eco's Foucault's Pendulum, is a total snooze-fest wasn't enough to make either of us reconsider our choice in a partner.  I can't imagine how hard it must be to click with someone over one thing, and then find that there are deep and irreconcilable differences in something potentially divisive, such as politics, religion, or morality.  But even so, it's worth getting past our tendency to self-essentialist reasoning.  After all, it's when we encounter, and stay connected with, people who aren't like us that we tend to learn the most.  That applies to friends as well as romantic liaisons; one of my best friends, the wonderful author Gil Miller (speaking of books you definitely need to read, you should check his out as soon as you're done reading this) is pretty different from me in a lot of ways, but we've formed a close friendship founded on a deep mutual respect and an understanding that both of us base our beliefs on thoughtful consideration -- and are willing to entertain the possibility of changing our minds.

And maybe that's what it boils down to; respect, willingness to listen, and an understanding that we might actually not be right about everything.  As author Robert Fulghum put it, "Don't believe everything you think."

In any case, the recent research does shed some light about how connections form in the first place.  The mutual friend who introduced Carol and me certainly got it spot-on.  And even if we can't agree about what books to read, it's good to know we still have lots in common, 23 years later.

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Cloud watchers

I've always had a fascination for the weather.  Especially violent weather; if I hadn't become a mild-mannered high school biology teacher, I'd have been a tornado chaser.  One of my favorite movies is Twister, and yes, I'm well aware of how ridiculous it is, but still.  Who didn't cheer when the Bad Meteorologist got smashed to smithereens, and the Good Meteorologist and his wife survived and decided they were still in love?

*looks around*

*silence*

Okay, maybe it was just me.  But still.  There's something compelling about weather, which is why I frequently give my wife urgently-needed updates about frontal systems in South Dakota.  Like everyone does, right?

*looks around*

*silence*

Anyhow, having been a weather-watcher for years, I was absolutely flabbergasted to find out that recently, the powers-that-be in the meteorological world have added twelve new types of clouds to the International Cloud Atlas.  Which is a book I didn't even know existed.  I mean, I've known since I was a kid and got a copy of The Golden Guide to Weather that there were different sorts of clouds, classed by height, shape, density, and pattern (if any) -- with wonderful names like altostratus and cirrus and mammatocumulus.  It honestly never occurred to me, though, that there was an entire atlas devoted to them, much less that there might be new ones.  After all, people have been watching the skies for millennia, not to mention describing it and drawing pictures of it.  How could they see anything truly new?

Well, it turns out that some of the new ones only form under really specific conditions.  Take, for example, one of the newly-classified cloud types, named cavum, sometimes known as a "hole-punch cloud" or a "fallstreak hole."  This occurs in an altocumulus cloud bank, when something causes sudden evaporation in a region, leaving behind a hole through which you can see the blue sky.  It's sometimes triggered by an airplane or even a meteor.

A cavum formation in Austria in 2008 [Image licensed under the Creative Commons H. Raab (User:Vesta), HolePunchCloud, CC BY-SA 3.0]

Another is the volutus, or "roll cloud," often associated with windy weather near bodies of water, and thought to be caused by a soliton wave -- a single, stable standing wave front:

A volutus cloud, Punta del Este, Maldonado, Uruguay, 2009 [Image licensed under the Creative Commons Daniela Mirner Eberl, Roll-cloud, CC BY-SA 3.0]

Another new one is the murus cloud, or "wall cloud."  Although this one has been seen many times, especially if you live in the midwestern United States, it just recently received its own nomenclature.  It's a part of a cumulonimbus formation -- the kind of cloud that gives rise to thunderstorms and tornadoes -- and results from an abrupt lowering of the cloud base.  This indicates the area of strongest updraft, which is why murus clouds are a good indication that it's time to head to the storm cellar.

A murus cloud near Miami, Texas, 1980 [Image is in the Public Domain courtesy of the National Oceanographic and Atmospheric Administration]

One last one is the asperitas formation, which has an undulating, underwater appearance.  While they look threatening, they're more often seen after a thunderstorm has passed, and usually dissipate quickly without any further violent weather.

Asperitas clouds over Talinn, Estonia, 2009 [Image licensed under the Creative Commons Ave Maria Mõistlik, Beautiful clouds, CC BY-SA 3.0]

Anyhow, I was really surprised to hear that those only recently got their own official classification.  I guess it just goes to show that there is still a lot to be learned from the things we look at every day.  Speaking of which, it's time for me to check the NOAA forecast site and see about those frontal systems in South Dakota.  Carol is waiting for her update.  You know how it goes.

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Mammals of unusual size

When we've gone to the Museum of Natural History in Washington, D.C., I always gravitate toward the prehistoric animals.

I guess that's understandable enough, given that I made my career as a biology teacher.  Judging by the crowds, I'm not alone.  However, unlike most folks -- who seem especially taken by dinosaurs like T. rex and triceratops -- I always head toward the prehistoric mammals.

I love to picture what "endless forms most beautiful and most wonderful" (to pilfer a phrase from Darwin's Origin of Species) crawled, ran, jumped, scampered, and thundered across the planet long before we ever showed up on the scene.  Mammals have been around for a long time, a lot longer than you might think if you learned that "mammals arose once the dinosaurs were extinct" in grade school.  The first certain mammal fossils date from the late Triassic, about 225 million years ago, so at that point the non-avian dinosaurs still had around 160 million years to enjoy their hegemony before the double-whammy of the Chicxulub Meteorite Impact and the eruption of the Deccan Traps in India wiped them out.

The mammals were small for a while, of course.  Prior to the Cretaceous extinction, most of them fell into one of three groups; multituberculates (which looked superficially like rodents, but were only distantly related), eutriconodonts (a bit weasel-like, but again, not related), and spalacotheriids (something like a modern mole, but once again...).  None left any living descendants, and the biggest ones were the size of a small dog.

Understandable that they did what they could not to be noticed when there were loads of hungry dinosaurs around.

It's true that once the non-avian dinosaurs were wiped out, there was significant evolutionary pressure to diversify and get larger, to take advantage of the niches emptied by the mass extinction.  And one of the groups that got big fast were the brontotheres -- Greek for "thunder beasts."

They, like other mammal groups, started small.  They're perissodactyls -- the "odd-toed ungulates," a group that contains modern horses, rhinos, and tapirs.  And although they looked superficially like rhinos, their teeth show a closer relationship to horses.  One of the classic brontotheres is the slingshot-horned Megacerops (formerly named Brontops):

[Image licensed under the Creative Commons Creator:Dmitry Bogdanov, Megacerops-coloradensis, CC BY 3.0]

The reason this comes up is a paper last week in Science, which I found about from my author friend (and frequent contributor to Skeptophilia) Andrew Butters, in which a team from the University of Alcalá in Madrid used patterns of evolution in brontotheres to investigate Cope's rule -- that in the absence of other factors, larger individuals have a higher survival rate, and species evolve to get larger over time.

The results certainly seem to hold here.  The survival rate of brontothere species during the Eocene Epoch, from 55 to 34 million years ago -- their heyday -- is directly proportional to their size.  However, one corollary to Cope's rule is that when conditions suddenly change, large species are less able to respond flexibly, and are more prone to extinction.  Which is exactly what happened at the end of the Eocene; by the beginning of the next epoch, the Oligocene, the brontotheres were gone.

It was hardly the end of the large mammals, however.  Another perissodactyl group, the rhinos and their relatives, stepped in to fill the empty niches, and this led to the largest terrestrial land mammal known, Paraceratherium (formerly called Baluchitherium and Indricotherium).

[Image licensed under the Creative Commons Dmitry Bogdanov creator QS:P170,Q39957193, Indricotherium11, CC BY 3.0]

Standing next to Paraceratherium, you'd have come up to his kneecap.

If that's not scary enough, the Oligocene also saw mammals like the enormous Daenodon -- the name means "terrible teeth" -- which looked a bit like a pig on stilts:

[Image licensed under the Creative Commons Max Bellomio, Daeodon shoshonensis , CC BY-SA 4.0]

Oh, and there were also phorusrhacids stomping around the place.  Colloquially known as "terror birds."  Think of an enormous carnivorous ostrich on steroids, and you have the idea.

So yeah.  Even though I love hanging around in the prehistoric mammal part of the Museum of Natural History, it would be another thing entirely to go back there and actually try to survive.  An Eocene Park or Oligocene Park would be just as terrifying as a Jurassic Park.

Nature is red in tooth and claw, and all that sort of stuff.  Guess it always has been.

In any case, it does make me glad that the scariest thing I have to deal with around here are squirrels, raccoons, and the occasional coyote.  I'll take those over "thunder beasts," "terrible teeth," and "terror birds" any day.

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Picky eaters

Last week a gardener friend and I were talking about the fact that some plants are extreme specialists -- they only thrive in a very narrow range of conditions.

The classic example of this are orchids.  Virtually all orchid species only do well if you can somehow replicate the exact conditions of temperature, soil pH, soil mineral content, sunlight, and so on that they need.  Some also require the presence of symbiotic fungi (such as mycorrhizae) that infiltrate the orchid's roots and aid in nutrient and water uptake.  All of this is why if you ever are lucky enough to see an orchid growing in the wild, resist the temptation of digging it up and bringing it home for your garden.  The chances are nearly one hundred percent that all you'll succeed in doing is killing it in short order.  (Also, if you live in a place with laws against harming endangered species, you might be looking at serious fines if you get caught.)

It's an interesting question to consider why such extreme specialization evolves.  On first glance, it seems like it'd be better for all species to evolve toward becoming generalists -- able to handle a wide range of conditions.  The thing is that while generalists (like dandelions and crabgrass) do thrive just about everywhere, giving them a competitive edge in disturbed habitats (like cities) where not much else grows, they get beaten by the specialists in old, stable ecosystems.  The specialists have evolved to tolerate those specific conditions better than anything else.

It's why in old-growth rain forests, just about everything you see -- plant and animal -- is a specialist.  Along roadside ditches, they're all generalists.

Some recent research suggests that this drive toward specialization in stable habitats is very old.  A study of the distribution of animals in Ediacaran (very late Precambrian) sandstone in Australia found that some of the peculiar animals characteristic of these ecosystems showed a distinct preference for particular parts of the habitat -- a clear hallmark of specialization.

The researchers focused on a handful of species that have no living descendants, including Obamus coronatus (which looks like a French cruller) and the hubcap-like Tribrachidium heraldicum, one of the only known animals to have triradial symmetry.

Artist's reconstruction of Obamus coronatus [Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com/), Obamus NT, CC BY-SA 4.0]

Both animals were grazers, feeding on the microbial mat on the seafloor, but their habitat choices differed.  Obamus turned out to have a distinct preference for places where the mat was thickest; Tribrachidium was much more evenly dispersed.  And since both animals were of very low mobility -- similar to modern barnacles -- this didn't just reflect the chance arrangement of where they were when the a layer of sediment, probably stirred up by a storm or landslide, buried them for eternity.

This was a habitat choice -- and the first known example of specialization in the natural world.

"We think about the very oldest animals and maybe you wouldn't expect them to be so picky," said Mary Droser of the University of California - Riverside, who co-authored the study. "But Obamus only occurs where there is a thick mat, and it's a pretty sophisticated way of making a living for something so very old...  There are a limited number of reproductive strategies, especially for animals like these.  There are more strategies today, and they're more elaborate now. But the same ones used today were still being used 550 million years ago."

"It's not like studying dinosaurs, which are related to birds that we can observe today," said Phillip C. Boan, also of UC - R, and lead author of the new study.  "With these animals, because they have no modern descendants, we're still working out basic questions about how they lived, such as how they reproduced and what they ate...  This is really the first example of a habitat-selective Ediacaran creature, the first example of a macroscopic animal doing this.  But how did they get where they wanted to go?  This is a question we don't yet know the answer to."

It's fascinating that we can get some insight into the behavior of a species that lived so long ago, during a time where there was no life at all on land.  Imagine it -- everything alive is in the sea, and the continents were vast, barren expanses of rock, sand, and dust.  The first land-dwelling plants and animals wouldn't exist for another fifty million years (and even then, they were clustered around bodies of water; the central parts of the continents would have been lifeless for a great deal longer).  

But despite how alien this landscape would have seemed, organisms were already evolving through natural selection to have many of the same traits we see today -- including the fact that some of them, like modern orchids, know exactly where they want to be.

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