The wind beneath my wings

We're at a dire crossroads, here in the United States, with a president under investigation, foreign and domestic policy decisions being driven by far right political commentators, political appointees making statements implying they can curtail constitutionally-protected rights.  Looking at the news has become a daily exercise in fighting back a sense of horror.

So today, I'm going to consider: a rash of recent pterodactyl sightings.

I learned about this phenomenon over at Cryptozoology News, where aficionados of creatures that don't technically exist can go for updates.  It turns out that we've had a sudden spike in reports of giant winged creatures, inevitably described as "bat-like" although many times larger than the biggest bats.

And since such explanations as "the eyewitness was drunk, confused, or just making shit up" clearly aren't applicable here, we are forced to the conclusion that pterodactyloids didn't become extinct 66 million years ago, they stuck around and are now appearing in places such as Wisconsin.

In fact, the Wisconsin sighting is only one of many in the last few months.  This particular report tells of an anonymous (of course) eyewitness who last August was driving home one afternoon and saw "a weird thing flying in the sky."  The creature was estimated at being two meters in length, and had "skin on its wings instead of feathers."

"Like a bat," he said.  "It looked like a pterodactyl or some kind of angel."

For reference, let's consider each of these:

Fig. 1: A bat  [Image licensed under the Creative Commons Barracuda1983, Pipistrellus flight2, CC BY-SA 3.0]

Fig. 2: A pterodactyloid [Image is in the Public Domain]

Fig. 3: An angel [Image is in the Public Domain]

So I think we can all agree that it'd be easy to confuse the three.

But our gentleman in Wisconsin isn't the only one to see a strange flying creature recently.  In November, a woman in Chester County, Pennsylvania saw a huge thing with wings while she was zooming down the interstate.  "I realized just how big it actually was," she said.  "The wingspan was twice the width of the car, as it flew over it and headed straight toward my car.  The feathers were black, or very dark brown.  As it flew over my car, I ducked a bit, to look up at it, through the windshield.  It was amazing to see such a beautiful sight. If I hadn’t been driving so fast – the speed limit is 70 mph – I could have attempted to take a photo."

An even bigger one was spotted only a few days later in Ohio.  A woman was driving with her fiance in Ravenna, Ohio, and stopped at a stoplight, only to see something enormous gliding overhead.  "It was two or three times larger than our SUV," she said.  "It had elbow-like wings.  It was darker than the sky.  The thing was huge."

The most recent sighting was just last week, once again in Pennsylvania, which seems to have more than its fair share of pterodactyls.  This time, a 47-year-old construction worker said he was out cutting firewood when the thing flew over.

"A large shadow appeared above me," he said.  "I ran inside to grab my phone, but by the time I came outside the bird was gone.  I’ve been terrified to go outside since that event."

He described it as a "green bird with a twenty-foot wingspan, covered in scales, [with] a spike on the end of its tail and razor-sharp talons."  He added, "It looked like a lizard."

Once again, for reference:

Fig. 4: A lizard.  [Image is licensed under the Creative Commons SajjadF, Lizard - e, CC BY 3.0]

So apparently, what we have here is a prehistoric-looking lizard angel bat-bird.  At least all the eyewitnesses agree on the fact that they're huge.

For my loyal readers in Wisconsin, Ohio, and (especially) Pennsylvania, keep your eyes on the skies, and let me know if any enormous winged creatures soar over.  Feel free to report your sightings here.  I realize seeing something like this could be scary, but the upside of it is that it'll take your mind off Mitch McConnell and Donald Trump, so as far as I'm concerned, bring on the pterodactyls.

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This week's Skeptophilia book recommendation is a little on the dark side.

The Radium Girls, by Kate Moore, tells the story of how the element radium -- discovered in 1898 by Pierre and Marie Curie -- went from being the early 20th century's miracle cure, put in everything from jockstraps to toothpaste, to being recognized as a deadly poison and carcinogen.  At first, it was innocent enough, if scarily unscientific.  The stuff gives off a beautiful greenish glow in the dark; how could that be dangerous?  But then the girls who worked in the factories of Radium Luminous Materials Corporation, which processed most of the radium-laced paints and dyes that were used not only in the crazy commodities I mentioned but in glow-in-the-dark clock and watch dials, started falling ill.  Their hair fell out, their bones ached... and they died.

But capitalism being what it is, the owners of the company couldn't, or wouldn't, consider the possibility that their precious element was what was causing the problem.  It didn't help that the girls themselves were mostly poor, not to mention the fact that back then, women's voices were routinely ignored in just about every realm.  Eventually it was stopped, and radium only processed by people using significant protective equipment,  but only after the deaths of hundreds of young women.

The story is fascinating and horrifying.  Moore's prose is captivating -- and if you don't feel enraged while you're reading it, you have a heart of stone.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

There were giants in the Earth

It's always a peculiar kind of joy to me to find out I wasn't understanding something correctly.

I know, it's an odd thing to get excited about, but I find the process of refining my comprehension of the universe to be a thrill.  I vividly recall when my freshman physics teacher demonstrated via a clever apparatus that if you shoot a gun horizontally, and simultaneously drop a bullet from the same height, the two bullets hit the ground at exactly the same time.

It didn't seem possible, but I couldn't argue with experimental evidence right in front of my eyes; the vertical and horizontal components of velocity are completely independent of each other.

And my picture of the world shifted a little bit.

Here's another one: how many of you have heard that before the dinosaurs became extinct when the Chicxulub Meteorite hit 66 million years ago, all the lineages related to mammals were small and fearful, scampering about in the shadows to avoid the fierce "terrible lizards" at the top of the food chain?  Any primitive mammals that grew too large, the story went, would either (1) be turned into lunch, or (2) be stepped on and converted to a Primitive Mammal Pancake.

Well, check off another piece of conventional wisdom as "refuted."  Because a recent discovery near the town of Lisowice, Poland, dating from the Late Triassic -- 220-odd-million years ago, right as the dinosaurs were approaching their peak -- shows that during this time, which was quickly leading up to the all-time-record-holders for terrestrial animals, behemoths like Brachiosaurus, Diplodocus, and the aptly-named Giraffatitan, there were already cousins to the lineage that led to mammals that were the size of African elephants.

This fossil, of dicynodont Lisowica bojani, looked like some bizarre cross between a turtle and a rhinoceros.  Here's an artist's reconstruction of Lisowica:

[Image licensed under the Creative Commons Creator: Dmitry Bogdanov, Dicynodont from PolandDB, CC BY 3.0]

Lisowica is so large, said Tomasz Sulej, paleontologist at the Polish Academy of Sciences's Institute of Paleobiology in Warsaw, that at first he and his team didn't recognize it as a dicynodont.  Its estimated mass is nine tons -- as much as a full-grown male elephant.

"Who would have ever thought that there were giant, elephant-sized mammal cousins living alongside some of the very first dinosaurs?" said Stephen Brusatte, a vertebrate paleontologist at The University of Edinburgh.  "We've always thought that early mammals and their relatives retreated to the shadows while dinosaurs rose up and grew to huge sizes.  That's the story I tell my students in my lectures.  But this throws a wrench into that simple tale."

But that's what's cool about science, isn't it?  You think you get what's going on, and nature turns around and astonishes you over and over.  

So picturing the prehistoric world dominated by T. rex and Triceratops and the rest of the big, lumbering creatures popular in children's books, with our cousins all the size of mice scurrying around and hoping not to get noticed, needs to be revised.  Right smack in the middle of the Age of Reptiles was a close relative of ours who looks like he was ready and able to defend himself.

And maybe even turn some of the smaller dinosaurs into Dinosaur Pancakes.

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Ever wonder why we evolved to have muscles that can only pull, not push?  How about why the proportions of an animals' legs change as you look at progressively larger and larger species -- why, in other words, insects can get by with skinny little legs, while elephants need the equivalent of Grecian marble columns?  Why there are dozens of different takes on locomotion in the animal world, but no animal has ever evolved wheels?

If so, you need to read Steven Vogel's brilliant book Cats' Paws and Catapults.  Vogel is a bioengineer -- he looks at the mechanical engineering of animals, analyzing how things move, support their weight, and resist such catastrophes as cracking, buckling, crumbling, or breaking.  It's a delightful read, only skirting some of the more technical details (almost no math needed to understand his main points), and will give you a new perspective on the various solutions that natural selection has happened upon in the 4-billion-odd years life's been around on planet Earth.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

Fish tales

Today's topic comes from Cool News in Paleontology.

I was alerted to this story because I was perusing science research sites and saw a photograph that looked, to my untrained eye, like a Croc shoe with eyes and a pine cone stuck on the heel.  After saying, "What the hell is that?" I found that it was a reconstruction of a primitive vertebrate called a placoderm, or armored fish.  Lest you think my description is an exaggeration, there's the beast that caught my eye:

This led me to a paper in Science called "The Nearshore Cradle of Early Vertebrate Diversification," by Lauren Sallan, Matt Friedman, Robert S. Sansom, Charlotte M. Bird, and Ivan J. Sansom, wherein I found that this was by far not the weirdest-looking reconstructed critter in the study.  Here are a few others (all reconstructions by Nobumichi Tamura):

I particularly like the one on the lower left, which looks to me like someone took a fish and stuffed its head in a funnel.  I don't know why any of these other species became extinct, but I'm guessing the one on the lower left looked in the mirror and died of sheer embarrassment.

The research, though, is pretty damn cool.  The authors write:

Ancestral vertebrate habitats are subject to controversy and obscured by limited, often contradictory paleontological data.  We assembled fossil vertebrate occurrence and habitat datasets spanning the middle Paleozoic (480 million to 360 million years ago) and found that early vertebrate clades, both jawed and jawless, originated in restricted, shallow intertidal-subtidal environments.  Nearshore divergences gave rise to body plans with different dispersal abilities: Robust fishes shifted shoreward, whereas gracile groups moved seaward.  Fresh waters were invaded repeatedly, but movement to deeper waters was contingent upon form and short-lived until the later Devonian.  Our results contrast with the onshore-offshore trends, reef-centered diversification, and mid-shelf clustering observed for benthic invertebrates.  Nearshore origins for vertebrates may be linked to the demands of their mobility and may have influenced the structure of their early fossil record and diversification.

They also bring up an interesting conjecture; that the tougher anatomy, and especially the presence of a backbone to protect the dorsal nerve cord, might have arisen because of the rough-and-tumble nature of near-shore ecosystems -- you have to be tough or you'll get battered to pieces by the waves.

That, in fact, is why this study was such a mammoth undertaking.  "The main problem is that the fossil record [of vertebrates] is absolutely terrible for the first fifty million to one hundred million years of their existence," said paleobiologist Lauren Sallan of the University of Pennsylvania, in an interview with Science News.  "And when [there are] fossils, they’re in tiny pieces.  It’s hard to tell what exactly’s going on."

The researchers put together the pieces of 2,827 fossils that date to the age range they were studying, and came to the conclusion that all vertebrates trace their lineage back to shallow, near-shore environments.  So maybe I shouldn't laugh at Pine Cone Butt and the Spotted Funnel-Head.  They could be my great-great-great (etc.) grandparents.

I've always had a fascination for paleontology, and this study impresses me not only for its breadth but for what it tells us about our own ancestry.  The forces of evolution have created some amazing-looking creatures, and it's wonderful that we're getting a look into where they may have lived.  It does bear mention, however, that even with the thoroughness of the Sallan et al. study, we're still barely scratching the surface.  We only know about the species that left fossils behind -- which by some estimates is less than a hundredth of a percent of the species that were around at any given time.

So imagine what it would be like to go back there and see it for yourself, back to a time when there was not a single species of plant or animal around that exists today.  Mind-blowing, no?  As the old adage goes, the only thing that is constant is change -- and that is especially true with the natural world.

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The Skeptophilia book recommendation of the week is a must-read for anyone interested in languages -- The Last Speakers by linguist K. David Harrison.  Harrison set himself a task to visit places where they speak endangered languages, such as small communities in Siberia, the Outback of Australia, and Central America (where he met a pair of elderly gentlemen who are the last two speakers of an indigenous language -- but they have hated each other for years and neither will say a word to the other).

It's a fascinating, and often elegiac, tribute to the world's linguistic diversity, and tells us a lot about how our mental representation of the world is connected to the language we speak.  Brilliant reading from start to finish.

Relics of a lost world

There are times that I get impatient with people doing what I call hypothesizing in a vacuum -- coming up with pointless "what ifs" that are unverifiable.  A lot of it seems to me to be useless mental messing-about that doesn't tell us anything new about how the universe actually works.

So it was a little surprising that I reacted as positively as I did to the paper that appeared last week in the International Journal of Astrobiology called, "The Silurian Hypothesis: Would It Be Possible to Detect an Industrial Civilization in the Geological Record?" by Gavin Schmidt and Adam Frank.  The authors write:

One of the key questions in assessing the likelihood of finding such a civilization is an understanding of how often, given that life has arisen and that some species are intelligent, does an industrial civilization develop?  Humans are the only example we know of, and our industrial civilization has lasted (so far) roughly 300 years (since, for example, the beginning of mass production methods).  This is a small fraction of the time we have existed as a species, and a tiny fraction of the time that complex life has existed on the Earth’s land surface (∼400 million years ago, Ma).  This short time period raises the obvious question as to whether this could have happened before.  We term this the "Silurian Hypothesis."

You're reading this correctly; the authors are trying to parse whether we could detect the presence of an industrial civilization on Earth -- if it last existed, say, 250 million years ago.

They're not the first ones to think about this.  It's showed up in fiction, most notably in the short story "At the Mountains of Madness" by H. P. Lovecraft, wherein some explorers in Antarctica discover a colossal ruin that is not centuries, or even millennia, old, but tens of millions of years old -- when Antarctica was far north of its present location and had a tropical climate, and when it was inhabited by an intelligent civilization that was decidedly not human.  Being Lovecraft, of course this discovery presages several of the main characters losing important body parts, but I still remember that when I first read this story, when I was maybe fifteen years old, it wasn't the horror element that struck me most; it was the idea that maybe 90 million years ago, the world hosted a non-human intelligence of which most of the traces had been wiped out.

Schmidt and Frank first look at the likelihood of we ourselves becoming fossils, and they conclude that the answer is -- it's not very high:

The fraction of life that gets fossilized is always extremely small and varies widely as a function of time, habitat and degree of soft tissue versus hard shells or bones.  Fossilization rates are very low in tropical, forested environments, but are higher in arid environments and fluvial systems.  As an example, for all the dinosaurs that ever lived, there are only a few thousand near-complete specimens, or equivalently only a handful of individual animals across thousands of taxa per 100,000 years.  Given the rate of new discovery of taxa of this age, it is clear that species as short-lived as Homo sapiens (so far) might not be represented in the existing fossil record at all.

So the mind-blowing outcome of this reasoning is that the vast majority of species that have ever lived left no fossil record at all -- and that our knowledge of prehistoric life is so scanty that using the word "incomplete" to describe it is a woeful understatement.

[Image courtesy of Wellcome Images and the Wikimedia Commons]

As far as our artifacts, they're not much more hopeful:

The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009) speculates about preservation of objects or their forms, but the current area of urbanization is less than 1% of the Earth’s surface, and exposed sections and drilling sites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.  Note that even for early human technology, complex objects are very rarely found. For instance, the Antikythera Mechanism (ca. 205 BCE) is a unique object until the Renaissance.  Despite impressive recent gains in the ability to detect the wider impacts of civilization on landscapes and ecosystems, we conclude that for potential civilizations older than about 4 Ma, the chances of finding direct evidence of their existence via objects or fossilized examples of their population is small.

Of course, the thing is, all it would take is one single artifact; you don't need an entire city to be preserved (as it was in Lovecraft).  We've made a number of very durable things -- of which, surprisingly, glass is one of the most resistant.  Most metal objects corrode on the scale of a human lifetime, much less millions of years; and plastics, long thought of as indestructible, are likely to break down to microscopic dust within a few centuries.  Any Jurassic-era plastics would long since be undetectable.  But a single glass marble or fragment of a drinking glass, encased in sediment -- that'd definitely do the trick.

Schmidt and Frank aren't the only scientists to consider the question.  Alan Weisman, in his fascinating book The World Without Us, considers the sequence of events that would occur if humanity disappeared, and concludes that not only would life march on just fine, most of our impacts would be gone in short order.  Within three days, he says, all the lights would have gone out; the loss of electricity would have results like the entire New York City subway system, and most of New Orleans, flooding.  Structures in tropical climates -- like the Panama Canal and most cities within twenty degrees either side of the Equator -- would be overgrown and swallowed by jungle within a few decades.  Within five hundred years, Weisman says, just about all that would be left is aluminum cookware, plastic residue, some of the more durable glass objects, remnants of buildings, especially in dry climates, and monuments like Mount Rushmore.

And that's after five hundred years.  Which is 0.001% of fifty million years -- and even that time span doesn't bring us back to the extinction of the dinosaurs.

What's fascinating about this study is that Schmidt and Frank aren't trying to tell us that there have been ancient civilizations in previous eras; they're simply considering the question of whether it'd be detectable if there had been.  And the answer is: probably not.  Even such factors as an industrial civilization's impact on the climate and the chemistry of the atmosphere might not leave traces that would still be discernible a hundred million years later.  The authors end their paper thusly:

Perhaps unusually, the authors of this paper are not convinced of the correctness of their proposed hypothesis.  Were it to be true it would have profound implications and not just for astrobiology.  However most readers do not need to be told that it is always a bad idea to decide on the truth or falsity of an idea based on the consequences of it being true.  While we strongly doubt that any previous industrial civilization existed before our own, asking the question in a formal way that articulates explicitly what evidence for such a civilization might look like raises its own useful questions related both to astrobiology and to Anthropocene studies.  Thus we hope that this paper will serve as motivation to improve the constraints on the hypothesis so that in future we may be better placed to answer our title question.

Which is it exactly.  Science isn't just the description of what we know, it also asks questions like "What would the universe look like if X were true?"  The ability to create a model of some version of reality, and then see if the predictions of that model line up with the evidence, is a powerful tool for understanding.

So as bizarre as it seems, apparently it is likely that even if there were a highly advanced industrial civilization that got wiped out by the Permian-Triassic Extinction 252 million years ago (along with damn near everything else; paleontologists Jack Sepkoski and David Raup, who specialize in studying the cheerful topic of mass extinctions, have estimated that the Permian-Triassic event obliterated 95% of the species on Earth), we would probably not have a single detectable trace of it left.

But maybe, just maybe, there's an Eldritch Cyclopean City still awaiting discovery somewhere.  Like Antarctica.  If so, though, I'm not going to be the one who explores it.  When that happened in Lovecraft's story, it resulted in a number of people having their brains sucked out by Shoggoths.

Which could seriously ruin one's day.

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This week's featured book on Skeptophilia should be in every good skeptic's library: Michael Shermer's Why People Believe Weird Things.  It's a no-holds-barred assault against goofy thinking, taking on such counterfactual beliefs as psychic phenomena, creationism, past-life regression, and Holocaust denial.  Shermer, the founder of Skeptic magazine, is a true crusader, and his book is a must-read.  You can buy it at the link below!