Wings over Skye

I know it seems like I keep ringing the changes on this topic over and over, but... it never fails to astonish me how much the Earth has changed over geologic history.

Part of my fascination, I think, comes from the fact that this knowledge is so at odds with how it feels to be an actual inhabitant of the planet.  When you look around, it seems like things are pretty static.  Oh, there are changes -- volcanoes and earthquakes come to mind -- but however catastrophic those can be for local residents, the fact remains that they are, on a planetary scale, tiny effects.  To see the big shifts requires a much longer time axis, but if you have the perspective of one...

... wow.

Take, for example, the discovery of new species of pterosaur in one of the last places I can picture a pterosaur flying -- the Isle of Skye, Scotland.  Now a cool, windswept, rocky island chain with few trees and lots of grass and heather, the Hebrides (and the rest of the British Isles) were, during the Jurassic Period, a lush subtropical land only separated from what would become North America and Greenland by a shallow strait of ocean.

The configuration of the continents at the mid-Jurassic [Image credit: Ron Blakey, NAU Geology]

And flying over the forests of Jurassic Scotland were some of the coolest prehistoric beasts ever, the pterosaurs.

Dubbed Ceoptera evansae -- the genus name means "mist flyer," from the Gaelic word ceò, mist, which also gives the Isle of Skye its Gaelic name of Eilean a'Cheò, "misty island" -- the newly-discovered fossil was found in the Kilmaluag Formation and dated to about 167 million years of age.  Ceoptera was a smallish pterosaur, measuring about sixty centimeters from beak to tail tip:

[Image credit: Elizabeth Martin-Silverstone et al., Journal of Vertebrate Paleontology]

The era when Ceoptera was flying over the Isle of Skye was a point of great diversification amongst the pterosaurs, a process which would accelerate during the rest of the Jurassic and into the Cretaceous, ultimately resulting in species from fifty-centimeter-long Sordes pilosus to the six-meter-wingspan Quetzalcoatlus northropi.  Eventually, however, the entire taxon would be wiped out in the Cretaceous-Tertiary Extinction of sixty-six million years ago.

"The time period that Ceoptera is from is one of the most important periods of pterosaur evolution, and is also one in which we have some of the fewest specimens, indicating its significance," said Elizabeth Martin-Silverstone of the University of Bristol, who led the study, in an interview with Science Daily.  "To find that there were more bones embedded within the rock, some of which were integral in identifying what kind of pterosaur Ceoptera is, made this an even better find than initially thought.  It brings us one step closer to understanding where and when the more advanced pterosaurs evolved."

For me, the coolest part is trying to picture what the world looked like back then.  Even with our knowledge of plate tectonics and the fossils we have available for study, we still have only the shadowiest image of the Jurassic world.  Consider what doesn't fossilize -- colors, sounds, smells, behavior.  We can make some guesses about what those were like based upon modern organisms, but guesses they will always be, and many of them significantly off the mark.  (If you want a good laugh some time, look into "prehistoric animals that were reconstructed wrong" and find out how wildly inaccurate even the experts can be.  Fortunately, science self-corrects, and the fact that we now know they were wrong comes from better fossils and more sophisticated analysis -- but even so, we still have a vague and incomplete picture of what things were really like back then.  Oh, for a time machine...)

So that's our flight of fancy for today.  Prehistoric wings over the Isle of Skye.  Makes you wonder what things will look like in another 160 million years or so.  We'll have a whole new set of "endless forms most beautiful and most wonderful," to use Darwin's trenchant words -- ones we could not even begin to predict.

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Lords of the air

Ever since I was a kid, my favorite group of dinosaurs has been the pterosaurs.

These are one of the six groups of animals that independently evolved flight, or at least significant capacity for gliding (the others are insects, birds, bats, flying squirrels, sugar gliders, and colugos).  They had incredible diversity at their height, during the Jurassic and Cretaceous Periods, from the pint-sized Sordes pilosus (with a sixty-centimeter wingspan) to the almost unimaginably huge Quetzalcoatlus northropi (with a ten-meter wingspan, as big as a light plane).

Most of them were probably clumsy on the ground -- it's hard to imagine how Quetzalcoatlus got off the ground -- but in the air, they were nimble, maneuverable, and fast.  The smaller ones were probably insect-eaters; the larger ones likely fed on fish, although a terrestrial diet of small reptiles and mammals is also possible. 

What brings all this up is the discovery of a new species of pterosaur, one of dozens that have been identified from the Jehol Biota, a stupendous fossil deposit in northeastern China near Huludao.  This fossil bed has produced not only pterosaurs but incredibly well-preserved species of prehistoric birds and other vertebrates -- it's like a tapestry of late Cretaceous animal life.

"Pterosaurs comprise an important and enigmatic group of Mesozoic flying reptiles that first evolved active flight among vertebrates, and have filled all aerial environmental niches for almost 160 million years," said Xiaolin Wang, of the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences, who co-authored the paper describing the discovery.  "Despite being a totally extinct group, they have achieved a wide diversity of forms in a window of time spanning from the Late Triassic to the end of the Cretaceous period.  Notwithstanding being found on every continent, China stands out by furnishing several new specimens that revealed not only different species, but also entire new clades."

This includes the newly-discovered Meilifeilong youhao, belonging to the family Chaoyangopteridae, which is represented at the site by two other species that have been found nowhere else.

Meilifeilong looked like something out of a nightmare, if the artist's reconstruction is accurate (and probably even if it isn't):

[Image courtesy of artist Maurilio Oliveira]

The name means "beautiful flying dragon," which I doubt is what I'd say if I saw one, but what I'd say is borderline unprintable so we'll leave it at that.

It's astonishing to think of how long these creatures ruled the skies -- from the late Triassic until the very end of the Cretaceous, a time span of around 160 million years.  Had change not come in the form of the Chicxulub Meteorite collision, they might well still be here, soaring on thermals above our forests and lakes and oceans, the undisputed lords of the air.  And even if we now know them only from fossils, they still can't help but impress.

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Hunters in the skies

Despite what you might have gathered from movies like Jurassic Park, we know very little about the behavior and appearance of prehistoric animals.

The exceptions stand out because they're so rare.  We know that Cretaceous-era hadrosaur Maiasaura nested in colonies -- because paleontologists have found entire family groups fossilized in place, with nests, eggs, and young all together at the same time.  The large ornithopod Iguanodon seems to have traveled in herds, given the 1878 discovery of 31 individuals that all died more or less simultaneously in what is now Belgium.  The Cretaceous parkosaurid Oryctodromeus apparently spent a lot of time in underground burrows judging from remains found in Montana and Idaho.

And a handful of others.  Surprisingly, one of the most iconic dinosaurs from Jurassic Park -- the Velociraptor -- has never been conclusively shown to be a pack hunter (although it may have been), and almost certainly wasn't intelligent enough to figure out how to open the latch on a walk-in freezer.

So she may not have been such a Clever Girl after all.

As far as appearance, that can be even dicier.  From complete skeletons, scientists can use the position of muscle attachment points to make a good approximation at body contour, but there are a lot of structures without bones that wouldn't fossilize at all.  Consider, for example, that a fossilized elephant skeleton would show very little evidence of a trunk -- so future paleontologists probably wouldn't know it had one, and their reconstruction would look pretty different from reality.  When feathers or hair are preserved -- itself an unlikely occurrence -- scientists can guess at color and patterns from traces of pigments left behind, as with the feathered pterosaur whose tail feathers showed clear evidence of banding.

Other than that, it's pretty much all speculation based on analogy to modern species.  So it's a fair bet that if we time-traveled back to a hundred million years ago, we'd have a hell of a lot of surprises when we saw how those critters actually behaved, what they looked like, and what they sounded like.

This is why when there's a fossil that gives us a clue about behavior, it's pretty special.  Like the one described in a paper in Scientific Reports yesterday -- a fossilized squid that had a tooth from a pterosaur embedded in it.

The 150-million-year-old fossil, found in Germany, is of a thirty-centimeter-long individual of the prehistoric squid genus Plesioteuthis, but when the scientists looked carefully at it they found something extraordinary -- there was a long tooth fragment in the mantle, which after analysis they concluded came from the pterosaur Rhamphorhynchus.  I've always loved the pterosaurs -- they're far and away my favorite prehistoric animals (yes, I have favorite prehistoric animals.  Doesn't everyone?).  They vary in size from little Sordes pilosus, with a wingspan of only 0.8 meters or so, up to the mind-bogglingly huge Quetzalcoatlus, which was as long tip-to-tail as a giraffe and had a wingspan of twelve meters -- as large as a small airplane.  (Imagine what you'd do if one of those glided overhead while you were out picnicking.)

Rhamphorhynchus was on the small end of things, with a 1.8 meter wingspan.  It was a pretty cool-looking creature (I mean, as far as we can tell) -- with a long tail ending in a diamond-shaped rudder.

An amazingly well-preserved fossil of Rhamphorhynchus from Germany [Image licensed under the Creative Commons Mike Beauregard from Nunavut, Canada, Rhamphorhynchus gemmingi pterosaur, CC BY 2.0]

So the new fossil find gives us some interesting evidence for this beast's feeding behavior.  What it looks like is that it probably flew low over bodies of water, similar to what the remarkable birds called Black Skimmers do today, grabbing prey that ventured too near to the surface with their long, toothy beaks.  Only this time a Rhamphorhynchus lost its fight for dinner -- it might be that at thirty centimeters, the squid was too large or too heavy for it to pull out of the water -- and lost a tooth as well.  The squid went on to fight its battles for survival another day (as, probably, did the Rhamphorhynchus), only to end up as a fossil itself, still with the predator's tooth buried in its mantle.

This fascinating glimpse of how these hunters in the prehistoric skies found their prey is all the more cool for its rarity.  It's not often the remains of a long-deceased animal can give you hints about how it behaved when it was alive.  This lens into the past has allowed us to glimpse a diverse group that died out completely 66 million years ago -- flying dinosaurs that dominated the air of a long-lost world.

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The brilliant, iconoclastic physicist Richard Feynman was a larger-than-life character -- an intuitive and deep-thinking scientist, a prankster with an adolescent sense of humor, a world traveler, a wild-child with a reputation for womanizing.  His contributions to physics are too many to list, and he also made a name for himself as a suspect in the 1950s "Red Scare" despite his work the previous decade on the Manhattan Project.  In 1986 -- two years before his death at the age of 69 -- he was still shaking the world, demonstrating to the inquiry into the Challenger disaster that the whole thing could have happened because of an o-ring that shattered from cold winter temperatures.

James Gleick's Genius: The Life and Science of Richard Feynman gives a deep look at the man and the scientist, neither glossing over his faults nor denying his brilliance.  It's an excellent companion to Feynman's own autobiographical books Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think?  It's a wonderful retrospective of a fascinating person -- someone who truly lived his own words, "Nobody ever figures out what life is all about, and it doesn't matter.  Explore the world.  Nearly everything is really interesting if you go into it deeply enough."

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

Paleontological ghosts

When I was in elementary school, I developed a fascination with extinct prehistoric animals.  Not unusual, I realize; kids love big, powerful creatures with nasty pointy teeth.  But this interest has persisted for nearly fifty years.  The thought that millions of years ago, there were on the Earth strange beasts, the likes of which we will never see again, always raises in me a sense of wonder.  In the words of Charles Darwin, "There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved."

Whenever I run into someone who shares this interest, my first question is always, "What's your favorite?"  I had a student in my AP Biology class last year who is mighty fond of Anomalocaris, which in my mind has always had a rather Lovecraftian look:

[image courtesy of the Wikimedia Commons]

Another student has actually been on paleontological digs in North Dakota, and once told me he has a soft spot in his heart for the early mammal with the euphonious name of Didelphodon:

[image courtesy of the Wikimedia Commons]

Me, I've always had a thing for flying animals, so my favorite group is the pterodactyloids, the best of which is the impossibly wacky-looking Rhamphorhynchus:

[image courtesy of the Wikimedia Commons]

So it was with great interest that I read an article by Nick Redfern over at Mysterious Universe that claims that these guys might still be around.

Yes, you read that right.  Pterodactyls.  Big, leathery, weird flying reptiles.  In San Antonio, Texas, in fact.  Now, how there could be a breeding population of gigantic bird-lizards in Texas without people seeing them more often -- hell, given that it's Texas, without someone shooting one -- is a question that troubles Joshua P. Warren, investigator of all sorts of odd claims and author of the book Pet Ghosts.  

And it was undoubtedly the research for his book that drove Warren to an explanation regarding why people see pterodactyloids (and other prehistoric creatures), but said cryptids never leave any hard evidence:

They're the ghosts of extinct animals.

"It seems absurd to believe that pterosaurs might still be amongst us, but never, ever get captured or killed," Redfern writes.  "Could it be that, as Joshua Warren’s research suggests, we’re dealing with the ghosts of long dead pterodactyls?  It sounds bizarre, but if people live on after physical death, then why not animals, too?"

Well, yeah.  "If."  I'm not convinced on that last account, as you no doubt know.  And of course, the convenient thing about this explanation is that this means that the lack of evidence becomes, in some bizarre way, a support for the contention itself.  "Nothing there?  No fur, footprints, anything?  There you are, then.  It's a Ghost Saber-toothed Tiger."

So I'm still figuring that we're looking at eyewitnesses who were either (1) confused, (2) lying, (3) drunk, or (4) all of the above.  But that's unlikely to convince either Redfern or Warren.

And understand that it's not that I'm happy about this.  I'd love it if there was some way to see what these magnificent animals looked like when they were alive.  And if I couldn't see a live one, I'd settle for a ghostly one.  But unfortunately, I very much doubt if either of these is possible -- although next time I'm in Texas, I'll keep an eye out.  

Maybe the rare San Antonio Rhamphorhynchus will put in an appearance just for me.

A wing and a prayer

Like many biologically-minded types, I love dinosaurs and other strange, extinct animals.  My particular favorite group are the pterosaurs, which in my opinion are a level of awesome that has no parallel in any modern animal group.  (Well, seals and the big cats are close.  But my point stands.)  They varied in size from the tiny, furry Sordes pilosus, which was only 60 cm from wingtip to wingtip, to the impossibly huge Quetzalcoatlus, with a wingspan of over ten meters -- as big as a light plane.

Imagine what it'd be like if one of those glided past as you were mowing the lawn.

Unfortunately, none of us will ever have that experience, because the last of the pterosaurs died in the Cretaceous Extinction, 65 million years ago.  Apparently the group had been diminishing ever since Jurassic times, when they reached the peak of their diversity, but the asteroid collision that occurred at the "K-T Boundary" effectivevly knocked out the remaining species.

Well, that's what the paleontologists think, anyway.  If you ask young-Earth creationists, you get a different answer.

Take, for example, ObjectiveMinistries.org.  On an unintentionally hilarious page called "Pterosaurs: An Introduction," we find out that pterosaurs actually survived until the late Middle Ages, and were one of the species that gave rise to the idea of dragons:

Pterosaurs (ter’ə·sôrs) are flying reptiles with leathery or membranous wings attached to the sides of their bodies and supported by an elongated fourth digit on their forelimbs. They were created by the Lord on the fifth day of His Creation Week (Genesis 1:20-22) and were a constant presence in the skies over Eden, where they peacefully ate fruit and plants. After the Fall, many of their descendants degenerated to a carnivorous diet and became feared by man, although non-wicked specimens preserved on the Ark helped to temper this degenerative tendency after the Flood. Various Pterosaur kinds were common throughout Eurasia and Northern Africa up until the early Middle Ages and interacted extensively with Man. Today, although Evolutionists falsely insist that they are extinct, pterosaurs can still be found, hidden away in the unexplored wilds of our world.

We then are treated to a drawing that I guffawed over for about ten minutes:

 This picture has so many wonderful features that it's hard to pick out my favorite, but I think that the winner would have to be the way that the pterosaur's snout and wing fortuitously cover up Adam and Eve's naughty bits.  Also, is it my imagination, or does Adam look a little too much like Justin Bieber?

Anyhow, amongst the other fun things I learned on this website was that the creationists have dreamed up a new approach to making their mythology "scientific," which is called "baraminology."  Never heard of it?  Neither had I, until today.  It turns out that it hearkens back to the biblical idea of a biological "type" -- a "baramin," in their terminology -- and is a sneaky way of getting around the fact that there are now dozens of known, explained examples of one species becoming another (by the canonical definition of species as "a population of mutually interfertile organisms").  They explain away these scientifically-verified instances of evolution, several of which I looked at in greater detail in last year's post "Grass, gulls, mosquitoes, and mice," as somehow not counting because you don't have one "baramin" evolving into another.  "Unlike the incorrect Evolutionist model that supposes that life forms a continuous lineage from Mushroom to Monkey to Man," the ObjectiveMinistries website explains, "the Creation model -- supported by science and the Bible -- shows that the pattern of life is marked first and foremost by discontinuity.  When we step back and look at all the life on the planet, it is clear that we can group the various species into distinct baramins, and that the spaces between these baramins are discontinuities that no amount of Evolutionist fantasizing can bring together.  Humans (one baramin) do not form a continuity with apes (another baramin)."

So, it's the whole "microevolution but not macroevolution" foolishness again, not to mention the usual mischaracterization of what the evolutionary model actually says ("mushroom to monkey to man," my ass), with the added spice of claiming that the creationist model is "supported by science."

This last bit is especially humorous given a paper that just came out last week in Paleontologia Electronica, written by Phil Senter and Pondanesa D. Wilkins.  Senter and Wilkins, unlike the nimrods who write for ObjectiveMinistries.org, are actual scientists, and their paper -- "Late-surviving Pterosaur?" -- is a gem.

Apparently one of the creationists' pieces of "evidence" that pterosaurs didn't all die in the biblical Great Flood is a skeleton of a "dragon" that was studied, and drawn in detail, by 17th century Dutch engineer Cornelius Meyer.  Meyer's drawings of the skeleton were followed up by a reconstruction of what he thought the living beast had looked like:

So, of course, this has added fuel to the fire regarding pterosaurs surviving into modern times -- although why the survival of a prehistoric animal would support creationism is a bit of a mystery.  But since their arguments all basically boil down to stating a fact and claiming that god did it ("Pterosaurs!  Therefore god!  The human eye!  Therefore god!  Bananas!  Therefore god!  Ha ha!  We win!"), I guess that's not to be wondered at.

Be that as it may, it still did my heart good to find out that Senter and Wilkins did an intensive analysis of Meyer's drawings -- which, fortunately, were greatly detailed and scientifically accurate, even if his conclusions weren't -- and their conclusion is, unsurprisingly, that the "dragon skeleton" is a hoax.

The skull is from a dog.  The mandible is from a different dog.  The hindlimb is actually the forelimb of a bear.  The ribs are from a large fish.  The tail and wings are sculpted fakes, and do not match what is known from fossils about the morphology of pterosaur tails and wings.  In Senter and Wilkins' eloquent words:

The solving of the mystery of the zoological composition of Meyer's dragon puts to rest the notion that Italians encountered live pterosaurs in the seventeenth century. It also sheds light on a strange and little-remembered episode in Italian history.  The case involves superstition, rumor, political intrigue, shady dealings, mighty feats of engineering, the impressive talent of an artisan savvy enough to combine two dogs and a bear and a fish and make it work, and the sagacity of an engineer who risked his career to turn a potentially job-wrecking superstition to his advantage.  Such an episode deserves to be counted among one of the greatest zoological hoaxes of Renaissance Europe...  This piece of young-Earth creationist "evidence" therefore now joins the ranks of other discredited "evidence" for human-pterosaur coexistence and against the existence of the passage of millions of years.

To which I can only add:  Ha.  Take that.

I sometimes get asked, usually by science-minded laypersons, why I spend so much time fighting with the creationists.  What does it really matter if these people believe their Bronze-Age mythology instead of science?  And if that was all it was, I probably wouldn't be fighting them (laughing at them, maybe, but not fighting).  But this particular worldview comes with a desperate need to foist their view upon others, and (especially) to indoctrinate children with their anti-science, evidence-free way of explaining the world.  They're not content to believe what they want to, and discuss their silly beliefs in their churches; they want those beliefs taught in public schools, they want them written into biology textbooks, they want them respected (by mandate from state law) as somehow being on equal footing as reputable science.

And that's where I stop laughing, and put my fists up.

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Imaginary beasts and made-to-order worlds

One general tendency I see amongst woo-woos of all types is a sense that the world has to be a certain way because it "feels like it must be so."  It goes beyond wishful thinking; it's not just a Pollyanna-ish "everything will turn out for the best."  It's more that they espouse an idea because it appeals to them on an emotional or intuitive level -- not because it lines up with what is scientifically demonstrable (and sometimes, despite the idea in question being demonstrably wrong).

I ran into an amusing example of this just yesterday, from the desk of the always-entertaining Nick Redfern.  Redfern, you might recall, is a frequent writer for Cryptomundo and Mysterious Universe, and is a particular aficionado of Bigfoot and other cryptids.  You'd think that eventually, cryptid-hunters would tire of the hunt after repeatedly bagging zero cryptids, and would give up and say, "Well, I guess we were wrong, after all."  But no: they keep at it, coming up with progressively more abstruse explanations about why the cryptids aren't showing up.  We have Linda Jo Martin's idea, that Bigfoot can avoid us because he's telepathic; Erich Kuersten, instead, makes the claim that Bigfoots are aliens, and when they hear us coming they escape in their spaceships.  But if you think those are wacky ideas, you haven't heard nothin' yet. Wait until you hear what Redfern has in store for us!

He thinks that we can't catch any cryptids, because they are created by our overactive imaginations.

Well, okay, you may be saying; isn't that what you've been telling us all along?  A bunch of cryptid hunters go out a-squatchin', and they see a shadow and hear a noise in the woods, and their overactive imaginations turn it into a Bigfoot?  No, that isn't what Redfern is saying at all; when I said he thinks that cryptids are "created by our overactive imaginations," I meant it in its most literal sense -- that we generate these beasts from our minds, and then they become real, real enough for other people to see.

"Could it be that just like Mothra and the saga of the The Mothman Prophecies," Redfern writes,  "The Valley of Gwangi unconsciously inspired people to muse upon the possibility of real flying reptiles in and around the Texas-Mexico border? And, as a result, did phantom-forms of such beasts step right out of the human imagination and achieve a form of ethereal existence in the real world? Granted, it’s a highly controversial theory, but it’s one that parallels very well with the theories pertaining to so-called Tulpas and thought-forms."

Well, I'm sorry, if you start out your argument by citing Mothra, you've lost some credibility points right from the get-go.  And someone really ought to sit down the entire seven billion human inhabitants of the Earth and clarify for them all, simultaneously, what the definition of the word "theory" is, because I'm getting sick and tired of doing it piecemeal.  A "theory" doesn't mean "some damnfool idea I just dreamed up."  It also doesn't mean "an idea that could just as easily be wrong as right," such as the way it's used in the young-earth creationist's favorite mantra, "Evolution is just a theory."  A theory is a scientific model that is well-supported by evidence, and has (thus far) stood the test of experiment.  So, therefore, Redfern's "theory" about actual flying reptiles coming from the minds people reading a novel about pterosaurs surviving until modern time is not a theory, it's a loony idea with no scientific backing whatsoever.

But that's not my main point, here; what I find the most curious about all of this is that Redfern et al. seem to have the idea that just because some bizarre version of reality is appealing to them on an emotional level, that means that the world must work that way.  The universe, then, is somehow made-to-order, constructed to fit what we want, need, or expect the universe to be.  I find this an odd stance, because (plentiful as my other faults are) this is never something I've fallen prey to.  It seemed abundantly clear to me, from as soon as I was old enough to consider the point, that there was no special reason why my desires that the world be a certain way would have any bearing at all on the way the world actually is.  "Wishin'," as my grandma use to say, "don't make it so."

Or, to quote (of all people!) Carlos Castañeda, from Journey to Ixtlan, "Why should the world be only as you think it is? Who gave you the authority to say so?" And if my ending my discussion of this topic with a quote from Castañeda doesn't introduce enough cognitive dissonance into your day to rock your Monday, I don't know what more I could do.