microecos

They were crane flies (Tipula sp.) congrats to Steve and Ted!  Lots of interesting things to say about crane flies, but…no time now!

Holy crap.  I’m going to China tomorrow!  WTF!?  Suffice to say things will probably be even more quiet than usual around here for the next ten days, depending on my ability to break through the great red firewall.  Oh, who am I kidding, like I’m gonna spend my time blogging anyway!?

In the meantime, go check out my first (and last?) published piece of fiction which appears in the latest issue of Ins&Outs magazine.  From the contents, click “highlights” and scroll down.  You’ll be transfixed by the convoluted smear of ink while the meaning jets away unseen!

See you in a few days!

Naish and Witton’s revolutionary reappraisal of Azhdarchid pterosaurs is blowing up all over the interwebs! The PLOS paper is open access, Darren and Mark each have a post about the paper on their respective blogs and  they have launched a new Azhdarchid-themed blog shattering the ultra-niche-paleoblog specificity bar set by SV-POW!

Suffice to say there’s little I could hope to add, but in the grand tradition of the Nigersaurus as pooper-scooper I couldn’t resist calling everyone’s attention to another case of technology/biology convergence:

Wacky!

It appears that my flagrant photoshoppery successfully obscured the identity of last week’s amorous arthropods from all both contestants!  Here’s the original unmanipulated shot, less intimate perhaps, but certainly more revealing.  We’ll let the guessing run for another week…

No detailed hellasaur exposition today I’m afraid, I’m off to UCMP to…well, play with Triassic hellasaurs.  This seems to be an appropriate moment to bestow some mad props on Annie Alexander (pictured above, looking for Triassic hellasaurs in Nevada).  Sugar heiress, asparagus farmer and founding benefactress of UCMP,  Annie was sort of the anti-Paris Hilton of the early 20th Century.   By all accounts she was a totally inspiring and ground-breaking figure who contributed immensely to the growth of science on the west coast, both as a philanthropist and as a talented field naturalist.

Alexander discovered many important Triassic fossils in California and Nevada while accompanying Berkeley paleontologist John C. Merriam on collecting expeditions which she funded.  In fact, she discovered the type material of one of my favorite Triassic hellasaurs of all, which I’m going to check out right now!

Back around the turn of the century, I joined Friendster.  Everyone was doing it.  It took me a while to jump on the MySpace band-wagon I wasn’t sure if I really needed another social networking site.  Once again, I’ve succumbed to the evil force of peer-pressure and finally joined facebook.  I can already see my productivity going down the toilet…hey but at least I’ll have an active e-social life!

Had I any brains at all, or mad self-promotional skillz, I would have kept up better with the bug-sex here at microecos. Natura graphica continues to be one of my most frequently visited post–thanks in large part to traffic generated by a brief bit of link love Bora posted years ago–right behind the horrendously titled Oh, oh here she comes she’s a mantid eater, though that one seems mostly to draw in wayward Hall & Oates fans…

At any rate, the insects are copulating wildly this time of year and stroking the sex organs of plants with reckless abandon, sometimes both at the same time!  Since I’ve had such luck with the weekly installment format why don’t we start a Saturday Insexology series?

We’ll kick things off with a reader quiz: Anyone up for identifying the lusty couple pictured above? Too keep it from being too easy I tweaked the colors, though that itself is a subtle hint…  I’ll have the answer next week along with some fresh bug sex shots to share!

After a week of small accomplishments and a roughly commensurate handful of minor setbacks here we are, just where we left of last week…props to Zach Miller for contributing original artwork to this piece!!!

Every time I begin to feel marginally comfortable with the rampant absurdity of the biological world, nature always seems to have one more joker up her sleeve. In the Triassic, she seems to have been playing with a trick deck anyway. Yet even among the motley crew of enigmatic Triassic hellasaurs, Hupehsuchus stands out as one of the weirdest of the weird.

But, for all its appealing novelty, Hupehsuchus isn’t exactly a household word. Here’s the entire Wikipedia entry on Hupehsuchus:

Hupehsuchus is an extinct genus of ichthyopterygian marine reptile from the Middle Triassic of China. The type species is H. nanchangensis.

Spencer Lucas provides a more informative account in Chinese Fossil Vertebrates:

More unusual Middle Triassic marine reptiles from China are Nanchangosaurus and Hupehsuchus. These animals are known from complete and incomplete skeletons found in the Middle Triassic Daye Formation of Hubei. Nanchangosaurus and Hupehsuchus retain many characteristics of terrestrial precursors to the ichthyosaurs and may be a “missing link” between them and their non-aquatic ancestors. (Lucas 2001)

Similarly, Nanchangosaurus (a Hupehsuchian closely related to Hupehsuchus) gets a brief plug in this diagrammatic explanation of ichthyosaur evolution which appeared in a recent New Scientist article by Don Prothero, excerpted from his book Evolution: What the Fossils Say and Why It Matters.

Both authors see the hupehsuchians as “missing-links” between ichthyosaurs and their terrestrial forebears. However, despite what Wikipedia would have you believe Hupehsuchus is probably not an ichthyopterygian sensu stricto (an error on Wikipedia! shock, horror), but may well be the sister taxon to this group (Motani 1999). Inconveniently however, Hupehsuchus is probably a few million years too young to be a direct ancestor to the ichthyosaurs, and—given its suite of unique characteristics—its role value as a “missing-link” is perhaps limited.

The most thorough description of Hupehsuchus, and indeed one of the only scientific papers on the animal, was written by Robert Carroll and Dong Zhi-ming (1991). Their publication is the source of the majority of the info presented here—aside from my own speculative ramblings—and is highly recommended to anyone whose interest is sparked by this brief discussion.

As mentioned by my brief preview last week, Hupehsuchus possesses a bizarre assemblage of unique and convergent adaptations—so much so that Carroll and Dong subtitled their paper “the problem of establishing relationships.” Perhaps the strangest part of Hupehsuchus is its long, toothless skull which bears a striking (but almost certainly superficial) resemblance to a bird skull. In other aspects it more closely resembles other marine reptiles; like the ichthyosaurs it has a deep, laterally flattened body almost certainly reflecting an adaptation to aquatic existence. Likewise the fore- and hind-limbs are broad and flattened, an adaptation seen in many secondarily marine tetrapods including sea-turtles, icthyosaurs, plesiosaurs, mosasaurs, whales and manatees among others.

A row of bony plates (osteoderms) lines the back of Hupehsuchus vaguely calling to mind the armored placodonts, although the armor is not nearly as extensively developed in Hupehsuchus. Just below the armor, the neural arches of the vertebrae are bizarrely “bipartite” divided into upper and lower sections. It’s tempting to speculate that these “jointed” vertebral processes may have somehow augmented the protection offered by the dorsal armor, but, given that no similar structures are known in any living or other fossil vertebrates, understanding the functional significance of this feature is challenging. Like the back, the underside of Hupehsuchus was “armored,” protected by a combination of robust ribs and overlapping gastralia.

The osteoderms of Hupehsuchus would presumably have served a defensive role, but we don’t quite know what against. The recently described marine archosaur Qianosuchus (Li et al. 2006), a three-meter long predator with serrated teeth, comes from slightly younger sediments than those that bear Hupehsuchus, but might be an attractive model for a hypothetical hupehsuchivore. The robust ribs and gastralia may have also helped to make Hupehsuchus negatively buoyant, similar adaptations are seen in many aquatic tetrapods.

The unusal “beak-like” skull of Hupehsuchus invites the obvious question of what the heck this thing ate. Toothlessness itself is not a very helpful clue: penguins, baleen whales, turtles, and the extinct sirenian Hydrodamalis all lack teeth but differ strongly in their diets and feeding strategies. Perhaps surprisingly, Carroll and Dong suggest that Hupehsuchus may have possessed “material resembling baleen”! They note however that the relatively narrow skull,and flexible neck don’t seem to accord well with the notion that Hupehsuchus was a swimming suspension feeder.

On the other hand, a flexible neck and relatively slender narrow, toothless skull might be a good tool for probing for benthic invertebrates hiding in the sediment. Perhaps Hupehsuchus sculled along the bottom, arcing its beak to and fro through the mud and snapping up prey in a manner vaguely reminiscent of spoonbills or platypodes? A nice image, but probably impossible to prove without the serendipitous discovery of some feeding traces—something to keep your eyes peeled for the next time you find yourself poking around the Jialingjiang Formation…

One final anatomical quirk comes from an undescribed (to my knowledge) hupehsuchian that briefly made the news a few years ago. Wu Xiao-Chun and colleagues (2003) published a brief communication in Nature which announced the discovery of a polydactylous nanchangosaurid. That digits are frequently lost over evolutionary but almost never gained has long puzzled scientists, especially since heritable mutations which cause the development of extra digits are found in many animals, including humans. One exception to this rule are the ichthyosaurs, some lineages of which multiple both the number of finger bones and the total number of digits over their evolutionary history. The extra-fingered hupehsuchian might therefore suggest again a close relationship between these two very different marine reptile groups. Unfortunately, the fossil, which appears to be largely complete, only gets a very brief description in the half-page Nature write-up.

The Carrol and Dong paper uses Hupehsuchus to launch into a fairly strident critique of over adherence to the principle of parsimony. While this debate is far beyond the scope of this brief (well, it was supposed to be brief) post. Suffice to say, Hupehsuchus is a fairly clear testament that nature has a sense of humor, that, or a drinking problem.

(Complete refs list and maybe some additional images, coming soon!)

REFS:

Carroll and Dong 1991

Lucas 2001

Wu 2003

Can’t wait for the spam comments that one’s going to attract…

Despite the banshee wail of half-finished work scattered across desktops both virtual and real…I couldn’t bear to be a no show for Julia‘s upcoming version of Linnaeus’ Legacy. So what better way to maximize pleasure and minimize effort than reprint some of my favorite mnemonics for remembering the hierarchy of taxonomic nomenclature courtesy of wikiquote.

These are much more memorable than the fretful cries or grainy recreational habits of European royalty my elementary teachers were always on about…

• Kevin’s Penis Can Often Feel Genuinely Sticky
• Kermit Puked Cookies On Fozzie’s Green Sweater
• Kids Playing Chicken On Freeways Get Squished
• Kill Pretty Cheerleaders Often For Good Suprise
• Kinky Porno Cookies Ordered From Girl Scouts
• Kurt Puts Cheese On Fat Girls Stomachs

One hits a bit too close to home however:

• Kind Professors Can Often Fail Good Students

Back to work!

postscript-

Couldn’t stop musing about this as I tried to hammer out my research prospectus…finally came upon suitable summary, laced with typically microeconian astandard spelling and doltish wordplay:

Krazed paleontologists can obfuscate fossils generally / specifically.