The Hell Creek Oviraptorosaur — What Does It Mean For Chirostenotes pergracilis?

Since the 1990′s, a few specimens have been kicking around of a particularly large oviraptorosaur from the Late Cretaceous of North America. Unlike the specimens that form the backbone of the Chirostenotes/Caenagnathus complex, these specimens come from the Maastrichtian, and unlike the similar material recovered from the Horseshoe Canyon Formation and elsewhere, this material comes from the late Maastrichtian. The Hell Creek, to be precise.

Whether Clades Should Have No Name

I am posting this here because I don’t want to log down Darren’s blog with my comment, where he has posted his perspective on the new paper, so it’s going here.

Valentine Fischer, Michael Maisch, and a host of other authors have a new paper out in PLoS ONE dealing with the perennial issue of ichthyosaur taxonomy. There, they erect a new taxon Acamptonectes densus for an ophthalmosaurine ophthalmosaurid located in the Early Cretaceous, defying previous regards that ophthalmosaurids didn’t survive the end of the Jurassic. It is derived on a combination of features which are otherwise not held by an array of other taxa, including numerous autapomorphies; the morphology at hand is so distinctive that additional specimens from across Europe have been referred to the Acamptonectes umbrella, or to the type species, including a paratype from Germany, where the holotype derives from England. Darren Naish, one of the coauthors, has his own write-up at TetZoo.

SOPA, the Research Works Act, and Relative Evil

This one is greatly off-topic, but of much relevance to Science in general. Skip if you do not want to read further.

My, What Weird Teeth You Have!

Notosuchia is an odd group of crurotarsans, basal to the group of crocs including the modern forms and their earstwhile “croc-like” allies, or crocs that actually look like livign crocodilians to today. These are small to large crocs with often short snouts, large and few teeth, and highly heterodont dentition including rounded, bladed, leaf-shaped, or even chisel-like teeth; they will have either upright seeming limbs as predators, or shorter, robust limbs as herbivores and foragers.

Eyeballs Wired Backwards

This one is also off-topic in general, which is going to be a trend for a little while before I get back into the groove. Meanwhile, check out Scott Hartman’s awesome reconstruction of Spinosaurus aegyptiacus, drawing from suggestions Andrea Cau and I made (independently) on the positions and identities of the original material (discussed here and here).

Okay, on to the meat.

In Memoriam

Dan Varner, artist of things paleontological, has passed away, survived by his wife. I am immensely affected by this loss because Dan was one of those very open, cheery sorts who gave earnest advice and did great art. I met him in person in 1999 at the SVP in Denver, where he, to my utter shock and amazement, said he liked my art and pointed out a piece he specifically enjoyed to prove it. Artists sometimes want a measure of themselves from others, to know that there is an impact where their art is concerned. Dan affirmed this for me, I think, more than anyone ever had, because up until then, he was a name who made money from his art and was known and liked. That means something to me still.

The title banner for this website is crafted from the skull of Globidens dakotaensis, a taxon not much unlike the one Mike Everhart talks about here. Dan’s illustration graces the top of that post, and I still cannot think of Globidens without thinking of that image. The impact was enough that I am drawn back to the page whenever I contemplate this unusual mosasaur, which Dan got to illustrate for his friend, and so for now, it will always be my mental memorial to what Dan said to me back then.

[I'm sorry if the writing on this post is much more jumbled than mine usually is. It's hard to just think about this without some measure of emotionality slipping through.]

Recap-orama, 2011 Edition

I wanted to try out a “Best of” for this blog, as a way to pull back readers to things they may have missed, or to bring back attention to things they glossed over, or things I flubbed. Also, things I am proud of.

Holiday Hiatus

I’m going to take a break for a while while I collate my thoughts, focus on work, and spend some time piecing together a few projects (including handling Measuring Caenagnathus‘ Jaw, discussing reasons Why Eshanosaurus is Probably Not a Therizinosauroid, and trying to finish up my end of a project with another on a taxon closer to my longer-term interests). I may occasionally break this to discuss a paper, as I did recently with Denver Fowler et al.’s discussion on predatory behavior in eudromaeosaurs (the references therein include a link to the actual paper, which is well worth the read). Until I come back, I leave you all with this:

Dromaeosaurs are Terrestrial Hawks

Denver Fowler and colleagues have just published a series of papers dealing with the reconstruction of predatory behavior as indicated by the proportions, curvature, and anatomy of the pes in theropod dinosaurs. They began this study investigating birds, and the range of ecology and behavior exhibited by a variety of birds. Then they expanded this to that ever-curious group, dromaeosaurs. That is the topic of the current paper, by Denver Fowler, Elizabeth Freedman, John Scannella and Robert Kambic, who describe the pedal anatomy of Deinonychus antirrhopus in relation to its possible predatory capabilities, including the premises of previous authors who’ve inferred the foot was used in climbing (including up the sides of very, very large prey).

I Cannot Compel to Reason: Triceratops, We Done It Again

Earlier this year, Andy Farke took the opportunity of  a remodel to assess the skull of that classic of classic dinosaurs, Nedoceratops hatcheri. Formally named by Richard Swan Lull (completing a monograph that first OC Marsh had begun but uncompleted by hid death, and then resumed by John Bell Hatcher until his death), he presumed it may have been a pathological specimen, probably Triceratops (one of its species, many of which abounded at the time), owning to large irregular rather than concise fenestrae in the parietals and one of the squamosals; but he relented on the idea of its apparently unique features and coined the name Diceratops hatcheri. The name would be later found to be ironic.