Fluvial Mudstones are the new Candy Girls

I once wrote a paper entitled “Applying the Principles of Stratigraphy in an Analysis of Melodrama.” Sadly, this was long before There Will Be Blood came out.

This video by Grizzly Bear reminds me of that paper, for several reasons, but, I’ll spare you the golemy details.  I dig the layers of metaphor though, puns possibly not intended.

Anyone recognize the location?  Anza Borrego or something?  And presumably those flags in the first scene are a paleo site right?

Props to Radov for leading me, indirectly, to this video.

Photo from cigarettesandredvines.com

GEOLOGY FAIL

This post by an anthropogenic warming skeptic over at HuffPost contains a number of yowlers but this perhaps is my favorite:

Major solar minima (and maxima, such as the one during the second half of the 20th century) have also been shown to correlate with significant volcanic eruptions. These are likely the result of solar magnetic flux affecting geomagnetic flux, which affects the distribution of magma in Earth’s molten iron core and under its thin mantle.

I Support Scientific Triassicism

If 2008 is remembered for anything, surely it will come to be known as the year Triassic broke.

When you were a kid, the Triassic was an impossibly dreary place peppered with some generic economy-model dinosaurs.  Oh sure there were also some stupid looking synapids, a bunch of “thecodonts” and “eosuchians” or whatever, a mess of footprints, maybe a mass extinction event or two…but honestly, who gave a Morganucodon’s ass?

I mean, check out the short shrift the Triassic gets in Zallinger’s famous Age of Reptiles mural. “Dude, is that a Plateosaurus?  No way…sick!”

click to buy the t-shirt!

While Triassic dinosaur faunae may not be as a charismatic as those of the later Mesozoic, there are still plenty of reasons to be interested in what was going on on our planet between ~250 and ~200 million years ago.  Emerging from wake of the largest mass extinction event of all time, perhaps uncoincidentally, the Triassic was a time of dramatic evolutionary change.  A great wealth of new clades appeared in the Triassic–including the first “true” mammals, crocodilians, frogs, turtles, squamates, dinosaurs, pterosaurs, ichthyosaurs, sauropterygians, scleractinian corals, modern sharks, coccolithophores, several important insect groups, I could go on and on–this evolutionary overdrive is so pronounced that some even speak of a “Triassic explosion.” The end of the Triassic was marked by another pronounced extinction event, which although pale in comparision to the Permo-Triassic event may have paved the way for the rise of the dinosaurs although others maintain it was the rise of dinosaurs themselves that drove the extinction.

All of which makes this classic Onion article even more hilariously poingnant.  In fact, we “secular Triassicists” are witnessing something of a golden era.  Nick Fraser’s spectacular Dawn of the Dinosaurs, published in 2006 is a great resource for those interested in delving into the Triassic world, as visualized by the exceptionally talented Douglas Henderson.  However the pace of discovery and the renewed scientific interest in the Triassic is so pronounced that a revised edition is already needed.

In the mean time, here is my list of the top 5 Triassic news stories of 2008:

click to buy the t-shirt!

5) The Aeto-Contra scandal – The confusion and controversy surrounding the naming of a new species of the unusual armored hellasaurs known as aetosaurs exploded across the internets in early 2008 and blossomed into a full fledged “-gate” with its own website and everything.  While in the end, the “resolution” of the conflict left plenty to be desired, if it’s true that there is no such thing as bad publicity then perhaps the silver-lining to the scandal is a somewhat higher profile for those wacky Aetosaurs.

4) Kryostega the Crocomander and Gerrothorax the, uh, Toiletmander? – While large, freakazoid “amphibians” (i.e. non-amniote tetrapods) were diverse and widespread in the Paleozoic they gradually trickled out during the Mesozoic leaving only the extant lissamphibians.  However during the Triassic a number of impressive “amphibians” were still around kicking ass and taking names.  The antarctic Kryostega a 4.5 meter aquatic predator was in the news this year, as was the rather smaller Gerrothroax whose unusual head-lifting bite inspired some choice wordsmithing by headline writers across the globe.  Don’t miss Matt Celeskey’s awesome interactive Gerrothorax animation at the Hairy Museum of Natural History. (Speaking of Antarctica, the oldest known tetrapod burrows, sweet.)

3) Longisquama Lets its Freak Flags Fly – Even among the surreal host of Triassic creatures, Longisquama stands out as a weirdo.  Recent work on the bizarre skin appendages of Longisquama add to our understanding of this strange animal but still leave much room for future discovery…more on this later, maybe.

2) The Triassic (Blog) Explosion – No fewer than three, that’s right three Triassic themed blogs launched this year all of which are required reading for Triassophiles:

Life of the Madygen – triassiccritters.blogspot.com – Written by a paleontologist based in Germany, this blog highlights the important Triassic fossils of Central Asia, including the aforementioned Longisquama.  The outcrop photos are geo-porn at its finest.

Chinleana – chinleana.blogspot.com – The Chinle Formation is the most famous and arguably most important source of terrestrial Triassic fossils in North America.  Recent discoveries in the Chinle have shed light on the origin of dinosaurs, transformed our understanding of late Triassic stratigraphy and revealed a host of interesting hellasaurs all of which (and more) are fodder for Chinle expert Bill Parker.

Paleoerrata – paleoerrata.blogspot.com – Yet another expert on North American Triassic terrestrial vertebrates, Jeff Martz’s blog thus far has covered not just the evolutionary history of the Triassic but is also a font of wisdom for aspiring young bucks and does, er, un- or underemployed paleontologists.

1) Triassic Turtle Mania – Odontochelys and Chinlechelys: a one-two punch in the ongoing turtle evolution cage-match.  Confusingly each fossil is seen as a TKO by the respective rival camps, on the plus side both paint a picture of Triassic turtles as being more morphologically and ecologically diverse than ever imagined.  Both fossils sent ripples across the blogosphere as usual, the Hairy Museum of Natural History is an excellent place to start.

Coming in 2009 – The Return of the Enigmatic Hellasaur (including Thalattosaurs…I swear!).  See you next year!

Time’s Spiral in Arrow Canyon

On an autumn afternoon, Earl Wadsworth climbed up to the top of a ledge in a remote slot canyon in Nevada.  With a knife or a nail or some other tool Earl scratched a large cursive “E” into the limestone wall.  After some consideration the graffiti-artist gave up on the formal script and printed his full name across the rock.

Just below he added the date: “November, 14th 1920.”

Eighty-six years later, to the day, I found myself on the same ledge admiring Wadsworth’s handiwork. 

Something my body needs anyway…I like that.

As you’ll note from the logo over there, this marks the first issue of “blogger half-assedly opining about peer-reviewed publications when, really no one asked in the first place anyway.”  I’ll use this logo whenever I…well you get the picture.  Feel free to borrow the logo for your own half, or even whole-assed efforts.

Invert-workers are always carping¹ about vertocentrism, and of course they have a point: tardigrades are like a gajillion times radder than tyrannosaurs and it’s a shame that Discovery Channel programming doesn’t reflect this fact.  I guess they’re busy vetting questions for Cash Cab or whatever.  But it occurs to me: it’s actually unfair to resent vertebrates as a whole for this injustice because, let’s face it, aside from lamnids no one gives a swimming crap about fish.

I know, I know, cladistically speaking, tetrapods like Sue and me are just aberrant terrestrial fish. Aside from our freakish lineage however, the silent majority of “values” vertebrates (i.e fish) might as well be ostracods for all the press attention they get.  I mean, ostracodes. Whatever.  (Actually ostracods/es have a pretty good PR person these days).

A few cases in point²: Funisia, an ediacaran with all the charisma of a sodden mop head, got major press attention thanks to some good old fashion sexing up by the media.  Likewise, Martialis heureka, the recently discovered basal ant, is already generating major buzz³ well before the peer-reviewed paper announcing the discovery has even hit the presses.  And don’t get me started about Aptostichus stephencolberti.

Meanwhile, the discovery of a new and extraordinarily bizarre fossil fish, Hsianwenia wui, announced in last week’s issue of PNAS (Chang et al. 2008), sank with less of a splash than a 49 kg Chinese diver making a perfect entry⁴.  And that’s unfortunate, because if the public has an inordinate fondness for things with hydroxylapatite endoskeletons, well Hsianwenia is about as bony as they come.

Hsianwenia (which I’m pronouncing “shee-An-Wen-ya” until someone corrects me) was discovered in Pliocene lake sediments from the Qaidam basin on the north side of the Tibetan plateau.  Hsianwenia belongs to the largest family of freshwater fishes the Cyprinidae which also includes minnows, carp and goldfish among many others.  The uplift of the Tibetan plateau over the past several million years has created multiple small, isolated lakes and waterways.  This in turn has driven the evolutionary radiation of an endemic suite of Cyprinids.  These 100 or so species in 15 genera are grouped together the subfamily Schizothoracinae, known to the more poetically-minded as “snow trout” or “snow carp” (Qi et al. 2006).

While FishBase reports that the flesh of living schizothoracines is “much relished”, eating Hsianwenia would have been a chore.  That’s because unlike its relished relatives, Hsianwenia is characterized by a peculiar thickening of the skeleton.    This “pachyostosis” is so extreme that the authors state that the bones appear to leave little room for muscle.

Hsianwenia wui from Chang et al. (2008).

While no known living fish possess a similar super-skeleton, another extinct fish, Aphanius crassicaudus—from Miocene sediments on the northern margins of the Mediterranean—apparently independently evolved extremely thick bones.  Multiple specimens from both species demonstrate that the pachyostosis is not evidence of disease or disorder, but was a natural feature in each fish.  More over, this condition was amplified through the course of ontogeny with fish becoming progressively stouter as they aged.

What factors could have selected for this unusual evolutionary quirk not once but twice?  The sediments containing the two fish species—though separated by space and time—share some provocative mineralogical clues: gypsum and calcium carbonate.  Both of these minerals are calcium salts and their presence as inorganic precipitates suggests that the bodies of water these fish lived in had extraordinarily high concentrations of dissolved calcium and other minerals.

The authors of the recent paper suggest that the hypertrophied skeleton of Hsianwenia (and Aphanius) was a novel solution for ridding the body of excess calcium⁵.  By thickening their bones, these fish were able to sequester calcium before it built up to toxic levels within its tissues.  Chang et al. also speculate that the saline waters were toxic to other vertebrate species given the absence of other vertebrate fossils.  So, these strange fishes may have had no need to escape from predators and could afford to reduce muscle space and add bulky bone.  Pollen and, yes, ostracods/es provide circumstantial support for generally arid and saline conditions in and around the lake while the fish were thriving.

Hsianwenia’s solution to it’s hard-water environment worked pretty well for 200,000 years or so, allowing it to thrive in waters where no other fish could.  Of course, Mother Nature’s a vindictive bitch, and all evolutionary solutions are by definition, temporary.  A thick evaporite deposit capping the fish-bearing layers speaks to our tale’s tragic end: the aridification of the Qaidam basin continued, the lake dried up, the freaky thick-boned fish died, the end.

So there you have it: tectonics, climate, aqueous geochemistry, evolution, morphological novelty and million-year-old fossil fish bones scattered across the high desert.  A fish story worth telling.

And you thought fish were boring.

REFERENCES

Chang, M. et al. 2008.  “Extraordinarily thick-boned fish linked to the aridification of the Qaidam Basin (northern Tibetan Plateau).” PNAS 105: 13246-13251.

Porter, S. M. 2007.  “Seawater Chemistry and Early Carbonate Biomineralization.” Science 316: 1302.

Qi, D. et al. 2006. “Mitochondrial cytochrome-b sequence variation and phylogenetics of the highly specialized schizothoracine fishes (Teleosti: Cyprinidae) in the Qianghai-Tibet Plateau.” Biochemical Genetics 440: 270-285.

¹ As we’ll soon see, this is a hilarious pun.
² There is one, sort of.  Be patient.
³ I suppose I’m mixing hymenopteran metaphors here.
⁴ Credit where it’s due: a German science blogger has already written about Hsianwenia here (in German).
⁵ One hypothesis to explain the “explosive” evolution of organisms with hard parts in the Cambrian holds that changes in seawater chemistry (perhaps linked to tectonic activity) drove organisms to begin precipitating minerals to prevent toxic buildup inside their cells.  Subsequently these structures were exapted into shells and carapaces and bones and teeth ultimately triggering an adaptive arms race.  While this hypothesis is speculative and controversial recent research does support the importance of seawater chemistry in setting the patterns of biomineralization among various lineages (Porter 2007).

Woah.

Crazy story in Science Daily today about a paper recently published in the Bulletin of the Society of Historical Integrative Tautology. The paper describes Protardosuchus incendiensis, an extinct fossil reptile whose remains were recently discovered in Holocene beach sands outside San Francisco.

The authors suggest that the strange hollow, procumbent dentition were able to expel a pair of reactive fluids which, when mixed together in the presence of atmospheric oxygen would combust. Abundant charcoal in the beach sediments which yielded the sub-fossil are seen as strong circumstantial evidence for this novel adaptation.

Some carabid beetles have developed a similar, though scaled down chemical defense mechanism while among reptiles, a number of species of cobra can spray venom from their fangs. Protardosuchus’ pyrotechnic display was apparently far more impressive. As the Science Daily piece notes, the author’s aren’t certain if this behavior was defensive or related to prey-capture:

“Seriously, dude we have no effing clue,” says Melchior Neumayr, lead researcher on the new study. “It was probably all like ‘fffshhhh’ and then all like ‘BOUSCH!’ And then, then you’re like totally toast brohan. No thanks man, thanks, but no thanks.”

Most interestingly, this discovery marks the first post-Cretaceous occurrence of a hellasaurid hellasauroid hellasauriform in North America (while most authorities consider “Ogopogo” to be a “hellasaur” sensu lato, it’s almost certainly not a true hellasauroid). It’s tempting to imagine that the mythical “dragons” of Eurasian folklore were inspired by extinct old-world protardosuchians whose remains have yet to be discovered. In fact this pan-Pacific distribution would almost certainly confirm McCarthy’s (2003) argument that the Pacific basin didn’t open until the Mesozoic. Dude, seriously.

An artist’s reconstruction of Protardosuchus.

Refs:

Dennis McCarthy (2003) “The trans-Pacific zipper effect: disjunct sister taxa and matching geological outlines that link the Pacific margins” Journal of Biogeography 30 (10)

Neumayr, M et al. (2008) “Expirational autocombustion in a recently extinct Hellasaur from coastal California” Bull. Soc. Hist. Int. Taut. 56 (9 or 10)

Who Is Buried in Lincoln’s Tomb?

On February 12th, 1809, two visionaries emerged on opposite sides of the Atlantic. Both were cautious, erudite, soft-spoken men who were destined to transform the world in their own way.

In a letter to Asa Gray Darwin, a self-proclaimed supporter of the Union endorsed Lincoln’s Emancipation Proclamation:

Well, your President has issued his fiat against Slavery—God grant it may have some effect.

I don’t know if Lincoln ever picked up the Origin.

I suppose he was rather busy in the sixties. He is reported to have read (and enjoyed) Robert Chambers’ Vestiges. While this proto-evolutionary text was widely derided by the scientific community (including Darwin himself), it did mark a sincere effort to develop a rational history of life that accorded with the fossil record.

Growing up in Kentucky, it’s almost impossible that a young Abe didn’t encounter some of the abundant Paleozoic fossils that litter the state. And, in keeping with my previous rant about our fossilferous infrastructure, the stone which surrounds Lincoln’s tomb is packed with coral and brachiopod fossils.

Perhaps it’s no coincidence that Lincoln’s most famous address, delivered amongst fields tilled with fallen soldiers, begins with a declaration of historical context. History helps us to make sense of chaos and savagery of modern life. This is also where Karl Marx and L. R. Hubbard fit in.

But aside from that, Mrs. Lincoln how was the play?