Friday, February 27, 2009

Dawn of the carnosaurs: Shidaisaurus

Quickly on the Goss, Italian-language blog Theropoda (love the cladistic in-joke tag line) is reporting the description of a new early tetanuran (the group containing all theropods more advanced than the ceratosaurs) from China, Shidaisaurus jina. It was found in the upper Lufeng Formation, making it early Middle Jurassic in age, a critical and poorly understood tme in dinosaur history when many familiar groups were getting their start. Analysis shows it was closely related to Monolophosaurus. It's also similar to the possible early coelurosaur Gasosaurus, and sinraptorids, showing that many major lines of carnosaurs (and one line possibly leading to coelurosaurs) had already diversified by this time.

More on this species and its implications to come, hopefully!

Wednesday, February 25, 2009

Miragaia: So long, stegosaur

Here's another new species for you gosshounds: Miragaira longicollum, or "long-neck from Miragaia village, Portugal."

This is a new stegosaur with a twist--look at that neck!

Photo credit by Dr Octavio Mateus.

As Tom Holtz pointed out on the DML, first we had Brachytrachelopan, the stegosaur-like short-necked sauropod, and now Miragaia, the long-necked stegosaur. Then he cryptically adds that there's another new dinosaur coming out that wants to belong to a different suborder... Could it be a long-necked theropod? Not that we don't have any, but maybe a long-necked 'carnosaur'? Or a short-necked ornithomimid? Or a flying ornithopod? Stay tuned to find out!

As the Everything Dinosaur blog is speculating, Miragaia might have implications for the old debate (and SVP poster joke) about bipedal stegosaurs. Long necks usually mean high browsing, dontcha know. Well, the Goss would point to diplodocid sauropods (which are now known to have had straight necks held close to the ground for low browsing over a wide area) as possibly a better example. But given the long back legs of stegosaurs and very robust forelimbs of Miragaia (maybe for doing "push-ups" into a bipedal or tripodal stance?), and the fact that the neck is pretty high from the ground, so unless it was wading shoulder-deep in ferns... Well, who knows? More opinions likely to come!

Wednesday, February 18, 2009

Further goss on Panphagia

Quick update on the new, primitive sauropodomorph Panphagia:

Adam Yates, at his blog Dracovenator, has his own post about this critter with a juicy bit of goss that applies to the old, early dinosaur favorite Eoraptor. Eoraptor is variously considered to be a primitive member of the theropod branch of the saurischian tree. Makes sense, since it's a small bipedal carnivore like all other primitive theropods.

Apparently Panphagia and Eoraptor are so similar that Yates reckons the authors of Panphagia are implying that Eoraptor might actually be a primitive sauropodomorph itself! This would be a mighty cool turn of events, giving us the most primitive of primitive sauropods and a very theropod-like, fully carnivorous one to boot. There's no solid phylogenetic evidence for this yet but it hasn't really been tested for either. Keep an eye on how this shakes out in the future.

Picture of Eoraptor is public domain from Wiki Commons.

Iguanodon divided by (at least) 3


As anyone who follows ornithischian classification (all five of you) knows, the famous British ornithopod Iguanodon has been getting the chop in the last few years. One of the first dinosaurs to be found and named, Iguano has picked up dozens of species over the past century or so and, not surprisingly, as studies of iguanodont realtionships got more precise it became necessary to divvy most up into their own genera outside Iguanodon proper. Last year, researcher, artist, and screaming-biplane enthusiast Gregory S. Paul published a paper reviewing the genus and spun off two new genera: Mantellisaurus and Dollodon.

Now, word on the tubes is that David Norman has given a lecture called "Iguanodontians from the Wealden of Britain and Europe" in which he gave his own review of the genus and spun off a few extras. These aren't published yet and far be it from me to facilitate any claim-jumping or Iguano-gate scandals by naming them here. That being said, goss hungry dino fans can find the names in a DML post from today and on a few Spanish-language blogs including aragosaurus.com. As you'll see, one of the new names kind of sounds like it'd be more at home on the periodic table than a list of dinosaur taxa. Ornithischian workers are werid guys.

Norman also discussed Paul's new genera: he thinks Mantellisaurus is valid but reckons Dollodon should be kept as a species of Iguanodon. We'll problably have to wait for all this to hit the press before reaching any kind of consensus, but stay tuned to the Goss to see if anybody weighs in prematurely.

Picture of Dollodon is public domain from Wiki Commons.

Tuesday, February 17, 2009

New species: Panphagia

First up on the Goss, here's a new species of basal sauropodomorph. Panphagia protos (meaning "first all-eater," as in it's the earliest known member of the group and was likely omnivorous, unlike the later sauropods which ate only plants). (Note: it does not mean "chimp eater," contrary to a joking post at DinoForum! Pan is, of course, also the genus name of chimapnzees.).

Normally I'd write a bit more about it but this guy was published in the journal PLoS ONE, which is free, online, and licensed under Creative Commons, so I can even post pics:



Doesn't look very sauropod-like, but that's the idea. It's a very primitive form, close to the common ancestor of all dinosaurs, so you'd expect it to be pretty similar to other early dinosaurs like Saturnalia, Eoraptor, and the near-dinosaur Silesaurus.

Read the whole paper or download a pdf here.

Early Goss:
Thanks to the comment system on PLoS ONE, comments on the paper are already rolling in. The paper suggests the discovery of such a primitive sauropod in the early Carnian pushes the origin of dinosaurs back into the Landinian stage of the Triassic. Randy Irmis, however, pointed out that the dating system used to date the formation Panphagia comes from (Ischigualasto) is known to have been miscalibrated. It's actually from the mid-late Carnian stae, which means it's still possible dinosaurs arose in the Carnian after all.

Stay tuned for more hot Panphagia goss as it unfolds!

Welcome to DinoGoss

Welcome to DinoGoss, my half-baked attempt to jump into the paleo blog arena! The idea for this site is to act as an aggregation of paleontology-related news and rumors from all over the web. Hopefully, this will be a useful way to keep track of cutting edge paleo (is that an oxymoron?) for people who don't want to spend the time and energy to follow all the blogs, forums, and mailing lists out there. It'll also give me an excuse to weigh in on current paleo events.

So watch this space and don't be afraid to comment!