New Species of Tyrannosaur Discovered in Southwestern U.S.

A Bistahieversor sealeyi dinosaur skull found in the Bisti/De-na-zin Wilderness of New Mexico

Great, a name so hard to make sense of they had to provide a pronunciation guide.

Bistahieversor sealeyi - pronounced: bistah-he-ee-versor see-lee-eye.

From Discovery:

A newly found 29-foot-long tyrannosaur flashed more teeth than the well-known Tyrannosaurus rex, with which it shared a common ancestor, according to a paper in the latest Journal of Vertebrate Paleontology.

Remains of the badlands dinosaur, Bistahieversor sealeyi, were collected in the first paleontological excavation from a federal wilderness area, the Bisti/De-na-zin Wilderness of New Mexico. The dino's remains were removed VIP-style, airlifted by a helicopter operated by the Air Wing of the New Mexico Army National Guard.

"Bistahieversor sealeyi is the first valid new genus and species of tyrannosaur to be named from western North America in over 30 years," said co-author Thomas Williamson, curator of paleontology at the New Mexico Museum of Natural History.

It lived 74-75 million years ago, close to 10 million years before T. rex emerged. The earliest known tyrannosaurs date to about 167 million years ago and came from the American West, according to Carr. It is now therefore believed that the rough and tumble Tyrannosauridae family was born in the U.S.A.

Several features distinguish the new dinosaur, according to Williamson's partner on the project, Thomas Carr, who is director of the Carthage Institute of Paleontology and an assistant professor of biology at Carthage College.

It had around 64 teeth, while adult T. rex, had just 54.

More reports here and here

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Haplocheirus, the alvarezsauroid that looked normal

This illustration of Haplocheirus shows the short forelimbs and claws put the dinosaur in the alvarezsaur family

Abstract:

http://www.sciencemag.org/cgi/content/full/327/5965/571

Jonah N. Choiniere, X. Xu, J.M. Clark, C.A. Forster, Y. Guo, F. Han. 2010. A
Basal Alvarezsauroid Theropod from the Early Late Jurassic of Xinjiang,
China. Science 327:571-574 DOI: 10.1126/science.1182143

The fossil record of Jurassic theropod dinosaurs closely related to birds remains poor. A new theropod from the earliest Late Jurassic of western China represents the earliest diverging member of the enigmatic theropod group Alvarezsauroidea and confirms that this group is a basal member of Maniraptora, the clade containing birds and their closest theropod relatives. It extends the fossil record of Alvarezsauroidea by 63 million years and provides evidence for maniraptorans earlier in the fossil record than Archaeopteryx. The new taxon confirms extreme morphological convergence between birds and derived alvarezsauroids and illuminates incipient stages of the highly modified alvarezsaurid forelimb.

The Theropod Database blog takes issue with the claim that it represents a basal member of the Maniraptora.

CBC News:

A newly discovered dinosaur species is helping paleontologists figure out how bird-like characteristics evolved in dinosaurs that aren't directly related to birds.

The dinosaur, Haplocheirus sollers, was three-metres long with short, powerful arms and three claws on each hand. It is an early member of the alvarezsaur family, a strange group of dinosaurs characterized by stubby forelimbs and hands reduced to a single claw.

Haplocheirus is 63 million years older than any other members of its family, helping to clear up the evolution of the meat-eating dinosaurs, the theropods, which includes velociraptors and T. rex.

"Haplocheirus is a transitional fossil, because it shows an early evolutionary step in how the bizarre hands of later alvarezsaurs evolved from earlier predatory dinosaurs," said Jonah Choiniere of George Washington University, in a statement.

The alvarezsaurid Mononykus olecranus:

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Yet more extreme Triassic weirdness: Vancleavea

Congrats yet again to Sterling Nesbitt and colleagues on the publication of another one of those insane Triassic hellasaurs, this time the surreal archosauriform* Vancleavea campi (Nesbitt et al. 2009) [adjacent life restoration by Sterling Nesbitt]. Vancleavea was named by Long & Murry (1995) and is well represented by various bits and pieces from the Upper Triassic of the southwestern USA (interestingly, it seems to have been around for a long time: like, 20 million years or so). Its affinities were initially unclear: all that was clear was that it was a weird, armoured diapsid reptile, with relatively small limbs and a covering of assorted osteoderms. But, as everyone knows, a new, very well preserved, articulated skeleton was later discovered at Ghost Ranch Quarry in New Mexico, and this is the specimen described in the new paper. Finally, we know what Vancleavea is, and what it looked like...

* Archosauriformes corresponds with Archosauria of tradition, with Archosauria now being restricted to the archosauriform crown-group (the crocodilian-bird clade).

Vancleavea was about 1.2 m long and, as is clear from the reconstruction shown here (from Nesbitt et al. 2009) was long-bodied and short-limbed. It was covered in rows of osteoderms, and 30 particularly tall osteoderms formed a vertical fin along the top of the tail. The latter is totally unique (archosauriformes, and reptiles [and tetrapods!] in general, tend to use elongated neural spines to increase the depth of the tail) and suggests that Vancleavea was a semi-aquatic swimming animal, and thus very different ecologically from other basal archosauriforms.

The skull is also really weird...

The rest at Tetrapod Zoology

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Ardipithecus ramidus, human evolution & scientific hype

Two restorations of "Ardi", a 45% complete skeleton of Ardipithecus ramidus published in this week's issue of Science.

Laelaps has an interesting blog post on this lovely collection of fossils. My interest here is chiefly about the growing tendency amongst some scientists to endulge in marketing spin in relation to their discoveries.

While I can understand the desire to bring science to as wide an audience as possible, the danger is that difficult and complex things get dumbed down in the process and that frankly untrue, or at least exaggerated, claims are made.

So the distinction between "Ardi" and good science (in my opinion) on one side and Ida and spin doctoring on the other is an important one.

At long last, meet Ardipithecus ramidus

The stories of "Ida" and "Ardi" could hardly be more different.

Ida was a lemur-like primate that lived 47 million years ago in an area that is now Messel, Germany. Ardi was much closer to us; she was one of the earliest hominins and lived 4.4 million years ago in what would become known as Ethiopia.

When the bones of Ida were discovered they were held in a private collection for years before being sold for an undisclosed sum to paleontologist Jorn Hurum. The first bones of Ardi were found in the field in 1992 by paleoanthropologist Gen Suwa. Enough fossils were found for an initial publication two years later, but the search continued for years afterward. That search has yielded over 100 bones from Ardi's kind, representing about 36 individuals. Ardi is the most complete individual, with about 45% of the skeleton intact.

From almost the time of her acquisition by Hurum, Ida was groomed to be a star. The media company Atlantic Productions began to work with Hurum and immediately started the production of a book, several documentaries, and a bombastic public unveiling of a discovery they said would "CHANGE EVERYTHING." The scientists describing Ida were forced to rush their study to meet the deadline set by the company The bones of Ardi and her kin, by contrast, were scrutinized with great detail over 15 years. So secret was the study of her bones that some frustrated paleoanthropologists called it the "Manhattan Project of anthropology."

Ida was introduced to the public as the "ancestor of us all", but the science behind this claim was flimsy. She was more closely related to lemurs than to us. Ardi, however, sits relatively close to the base of the human (i.e. hominin) family tree. Whether our species can trace its ancestral heritage back through hers will be something that will be debated in the months and years to come, but she is nevertheless one of our closest extinct relatives.

Ardi, of course, is short for Ardipithecus ramidus, one of the earliest hominins found to date. Her skeleton (see image below), as well as bits and pieces of other skeletons of the same species, were described this week in a special edition of the journal Science.

The whole thing is well worth a read.

Additional reporting:

The New York Times

The Daily Mail

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Raptorex, the new tiny tyrant

Weighing only a fraction as much as Tyrannosaurus rex, the 125 million-year-old Raptorex nevertheless exhibits a similar body plan in this artwork depicting both species.

Who would have thought Tyrannosaurus rex had such a murderous "mini-me" in its family tree?

Not Stephen Brusatte, a paleontologist at the American Museum of Natural History. "This was completely unexpected," he said.

And not University of Chicago paleontologist Paul Sereno, who along with Brusatte and other colleagues figured out that the tiny tyrannosauroid had virtually all the lethal weapons brandished tens of millions of years later by a behemoth 90 times more massive.

"From the teeth to the enlarged olfactory bulbs, the enlarged jaw muscles, the enlarged head, the small forelimbs, the lanky, running, long hindlimbs with thick-pressed foot for hunting prey - we see this all, to our great surprise, in an animal that is basically the body weight of a human," he told reporters.

The 125 million-year-old fossil dinosaur, unearthed in China and dubbed Raptorex kriegsteini, is "as close to the proverbial missing link on a lineage as we might ever get for tyrannosaurs," Sereno said.

The researchers laid out their conclusions in a paper published online today by the journal Science.

Cosmic Log

More reports:

Chicago Tribune

USA Today

ScienceNews

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Armadillo-like Crocodile Fossil Found in Brazil

An ancient crocodile with armadillo-like body armor (above, a reconstruction of the fossil in an undated picture) roamed the arid interior of Brazil about 90 million years ago, say researchers who found the fossil in São Paolo state.

In addition to its unusual bony shield, the reptile could chew like a mammal, moving its lower jaw forward and backward, researchers said in July 2009.


RIO DE JANEIRO (Reuters) – Fossils found in Brazil are from a crocodile resembling a large armadillo that was a predator in the area around modern-day Sao Paulo state 90 million years ago, researchers said on Tuesday.

The 6.6-foot-long (two-meter-long), 265-lb (120-kg) crocodile, named the "Armadillosuchus," appears to have been unique to that area, the researchers at Rio de Janeiro's Federal University said.

The creature displayed some characteristics of an armadillo, with bony plates on its neck and back.

It had a carapace, a wide skull, a short, narrow snout, and relatively small, specialized teeth that make it distinct from any other crocodile discovered, the university said.

Full story at Yahoo! News

Also at National Geographic

Picture gallery here

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Land Of Improbable Dinosaur Pee

National Geographic asked Dr Thomas Holtz, a dinosaur paleontologist at the University of Maryland’s Department of Geology, to give a professional's reaction to Will Ferrell's new film Land of the Lost.

 

http://blogs.ngm.com/blog_central/2009/06/land-of-improbable-dinosaur-pee.html

 

It includes this explanation as to why you could not douse yourself in dinosaur urine, even if that was your thing:

 

For example?

 

[He] assumes that if he douses himself in hadrosaur urine …

 

And a hadrosaur is?

 

A duck-billed, plant-eating dinosaur.

 

Now, back to the urine.

 

He assumes that dousing himself will keep the predators from going after him. Everyone else would think the urine would attract the predators, which it does. They sniff him out easily. It’s a good gag, but the premise isn’t based on biology.

 

How so?

 

Dinosaurs wouldn’t pee lots and lots and lots of urine. They’re part of this group of reptiles called diapsids. Today’s diapsids are lizards, snakes, crocodiles, and birds. The way they get rid of nitrogenous wastes from their kidneys is not by peeing lots of liquid. It’s by excreting this white sticky paste. So when you find the white paste on your car, the bird hasn’t pooped on it; it’s peed on it. That way they conserve a lot more liquid than mammals or amphibians.

 

The pee mistake has been made before?

 

Even Walking with Dinosaurs got this infamously wrong. In one scene in this 1999 BBC documentary, a big predator marked its territory by peeing all over it. Mammals do that because we pee a lot. Reptiles wouldn’t.

 

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Virtual fossils reveal how ancient creatures lived

BEHIND the war of words over the significance of Ida, the 47-million-year-old primate fossil unveiled last week, a quiet revolution in palaeontolgy is unfolding. Thanks to a souped-up version of a technique better known for its use in medical diagnostics, we are gaining unprecedented insights into the way prehistoric creatures lived, breathed and grew.

The technique is X-ray computed tomography (CT). Though X-rays have been used to look into fossils since this type of radiation was discovered in 1895, the flat images it produced changed little over the following century. As recently as 2004, a review in The British Journal of Radiology (vol 77, p 420) saw little merit in X-ray images of fossils beyond acting as a guide to palaeontologists chipping away the rock encasing them.

CT changes all that.

Full article here New Scientist

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