Tuesday, January 29, 2013

Eosinopteryx: a ground-bound troodontid?

Welcome Eosinopteryx brevipenna to the gloriously fuzzy lineup of Chinese paravians!

Eosinopteryx is a new feathered dinosaur from the paleo treasure trove that is Liaoning Province, China. This tiny little fellow, sizing in at only around 30 cm long, was described as being a basal troodontid by the authors: it is extremely similar, skeletally, to Anchiornis, the fuzzy-footed woodpecker mimic famous for being the first dinosaur for whom a complete color study was performed. The fossil of Eosinopteryx, however, clearly lacks a feature for which Anchiornis is unique: it has no long feathers on the feet or ankles, and no tail feathers to speak of either.

It also appears to have rather blunt and short claws on the feet, whereas Anchiornis - tentatively assigned as a sister taxon to Eosinopteryx - had long and curved claws which appear to be the appropriate kind for climbing. Eosinopteryx is therefore considered to be a ground-running animal without the obvious adaptations for arboreality common to its brethren.

This has already been vehemently disputed in the paleo blogosphere, though. It's difficult to discount the possibility that legwings and tail feathers simply didn't preserve in the fossil, and that the animal would have had them in life. It has also been proposed that perhaps Eosinopteryx was a juvenile (most notably a juvenile Anchiornis), and the lack of defined legwings and retrices were a result of its youth and would have come in at adulthood. This is supported by its unusually large head and short snout, features commonly associated with juvenility in birds. However, the authors state that the animal is not a juvenile, as evidenced by closed sutures on the vertebrae - but then again, it has also been mentioned that closed sutures of this nature are sometimes found on animal embryos, so it may make no relevant difference.

In any case, the uncertain phylogenetic position of this pretty little paravian, as well as the general sentiment of "not convinced" by the paleontological community, leaves the importance of Eosinopteryx somewhat up in the air - a place the animal itself may or may not have been occupying.

Godefroit, P.; Demuynck, H.; Dyke, G.; Hu, D.; EscuilliƩ, F. O.; Claeys, P. (2013). "Reduced plumage and flight ability of a new Jurassic paravian theropod from China". Nature Communications 4: 1394. doi:10.1038/ncomms2389.

Saturday, January 19, 2013

Utahraptor at Dawn

Utahraptor stands in the shallows of the great early Cretaceous inland sea, looking out to the horizon as the sun rises. Utahraptor, though one of the largest dromaeosaurs, was certainly not always taking down large prey in a dramatic and bloody fashion. On this morning, these dromaeosaurs were not hungry enough to hunt, so they combed the beach for shellfish and protein minutiae washed in by the tide. A small flock of ornithocheiroid pterosaurs pass by above.

Tuesday, January 1, 2013

2013 Archosaurs Calendar

Through a collaborative effort over at the Hell Creek paleontology forum, myself and a group of other artists have put together a 2013 Archosaurs calendar! This calendar features, for each month, a dinosaur or other extinct archosaur that was discovered in that month. This includes new specimens and studies as well, such as the Micoraptor color study performed in March.

The cover features all of the individual art found within.

The calendar features art by a total of 11 talented artists, as well as the organization efforts by Albertonykus. Contributing artists include:

Renato Santos
Tom Parker
Moritz Dukatz
Guillaume Babey
Adrian Wimmer
Fabio Manucci
Vladimir Nikolov
Christian Masnaghetti
Elia Smaniotto
And myself.

Proceeds from all sales will go to the future production of a children's book on dinosaurs, which will be another Hell Creek collaboration. This project will be an educational effort featuring fully accurate illustrations and information, the like of which is sorely lacking in the current market for children.

In other words, if you buy this calendar, all profit will go to a very good cause!

Here are a few samples of the material in this calendar:

Pegomastax, the South African strange-toothed heterodontosaurid described in October, by Vladimir Nikolov.

A herd of Xenoceratops - a new ceratopsian described in November - on the move, by Chris Masnaghetti.

The December entry, by Elia Smaniotto, rounds out the year and features a parade of hypothetical discoveries that we're hoping to see in 2013, and includes a flightless pterosaur, a feathered sauropod, a sailed ornithopods, and many others.

Buy it here!