A Sick T. rex

Common Avian Infection Plagued the Tyrant Dinosaurs. 2009. E.D.S. Wolff, et al. PLoS One PLoS ONE 4(9): e7288.

A new study pins the demise of ‘Sue’ and other tyrannosaurs with similar scars on an avian parasitic infection called trichomonosis, caused by a single-celled parasite that causes similar pathologies on the mandibles of modern birds, raptors in particular.

The focus of the new study was a survey of lesions on the jaws of Sue and nine other tyrannosaur specimens. The lesions had previously been attributed to bite wounds or, possibly, a bacterial infection.

It is possible the infection in her throat and mouth may have been so acute that the 42-foot-long, 7-ton dinosaur starved to death, says Wolff.

The scars of combat among tyrannosaurs and other dinosaurs, Wolff notes, are not uncommon, but differ notably from the lesions that are the focus of the current study. The holes caused by trichomonosis tend to be neat and have relatively smooth edges, while bite marks are often messy, and they scar and puncture bone in ways that are not readily comparable.

"The lesions we observe on Sue suggest a very advanced stage of the disease and may even have been the cause of her demise," says Wolff. "It is a distinct possibility as it would have made feeding incredibly difficult. You have to have a viable pharynx. Without that, you won't make it for very long, no matter how powerful you are." link

McAbee Eocene Fossil Beds Lose Protection

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“The B.C. Paleontological Association has pulled out of an agreement signed last year with government to protect a renowned fossil bed near Cache Creek, B.C..

An official with the B.C. government also acknowledged there is no money for oversight at McAbee fossil beds. Monitoring of the site was one of the goals contained in the agreement designed to protect what one researcher called a world-class site now used as a tourist destination.

A memorandum of understanding (MOU) was signed last year with the province, B.C. Paleontological Association, Royal B.C. Museum and Thompson Rivers University.
Its goals included mapping and potentially expanding the fossil beds from the Eocene era, 50 to 60 million years ago, as well as monitoring finds and collecting and storing significant fossils at TRU.

“Because government pulled its funding the B.C. Paleontological Alliance has withdrawn from the MOU,” said TRU geology professor Ken Klein.

“Government didn’t do anything it said it would do. It’s unfortunate. There’s no money for anything.”

From the Kamloops Daily News.

Raid of The Dinosaurs!

Another great, goofy sci-fi dinosaur story for a Sunday afternoon from the early days of DC Comics care of Atomic Surgery.

Evolution of Weaponry in Female Bovids

Evolution of weaponry in female bovids. 2009. T. Stankowich and T. Caro. PRSB, Published online before print September 16, 2009.

saiga

Abstract: Weaponry is ubiquitous in male ungulates and is driven by intrasexual selection, but the mystery surrounding its sporadic presence in females remains unsolved. Female horns are often smaller and shaped differently to male horns, suggesting a different function; indeed, hypotheses explaining the presence of female horns include competition for food, male mollification and defence against predators.

Here we use comparative phylogenetic analyses to show that females are significantly more likely to bear horns in bovids that are conspicuous due to large body size and living in open habitats than inconspicuous species living in closed habitats or that are small. An inability to rely on crypsis or take refuge in deep vegetation has apparently driven the evolution of horns for defence against predators in female bovids, a finding supported by many field observations.

Typically, exceptions are small species where females are territorial (e.g. duikers) and use horns in intrasexual contests. Furthermore, we suggest that conspicuousness and territoriality hypotheses may explain other instances of female cranial weaponry (i.e. antlers and ossicones) in other horned ruminants.

Our phylogenetic reconstruction indicates that the primary function of horns in females is linked to antipredator defence in most clades, but occasionally to intrasexual competition in others.

More work on modern animals that can be used when considering the evolution of horned dinosaur ornamentation.

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Sunday Funnies

Today's reprint of Liberty Meadows by Frank Cho.

When Whales Walked Into The Water

Relationships of Cetacea (Artiodactyla) Among Mammals: Increased Taxon Sampling Alters Interpretations of Key Fossils and Character Evolution. 2009. M. Spaulding, et al. PLoS ONE 4(9): e7062.

Painting by the great Carl Buell

A new study shows that cetacean (whale) ancestors probably moved into water before changing their diet (and their teeth) to include carnivory; Indohyus, a 48-million year-old semi-aquatic herbivore, and hippos fall closest to cetaceans when the evolutionary relationships of the larger group are reconstructed.

"Indohyus is interesting because this fossil combines an herbivore's dentition with adaptations such as ear bones that are adapted for hearing under water and are traditionally associated with whales only."

The origin of whales, dolphins, and porpoises—with their highly modified legs and lack of hair—has long been a quandary for mammalogists. Recent genetic research has found that among artiodactyls, hippos are the cetaceans' closest living relatives.

Traditionally, the origin of whales was linked to the mesonychids, an extinct group of carnivores that had singly-hoofed toes. The recent discovery of Indohyus, a clearly water-adapted herbivore, complicates this picture (as new fossils often do) because of ear bones similar to those of modern cetaceans, which are theorized to help the animal have heard better while under the water.

To tease apart different potential evolutionary histories over 80 living and fossil taxa scored for 661 morphological and behavioral characters (such as presence of hair or the shape of and ankle bone). Forty-nine new DNA sequences from five nuclear genes were also added to the mix of more than 47,000 characters.

The team found that the least complex evolutionary tree places Indohyus and similar fossils close to whales, while mesonychids are more distantly related. Hippos remain the closest living relatives.

These results suggest that cetacean ancestors transitioned to water before becoming carnivorous but that the meat-eating diet developed while these ancestors could still walk on land. link

Born This Day: Winsor McCay

Sept. 26, 1987 – July 26, 1934

McCay was one of the great American artists of the last century. He is best known for his newspaper comic strip Little Nemo in Slumberland that ran from 1905 to 1914, and the animated cartoon creation Gertie the Dinosaur (1914). For this cartoon McCay hand drew each frame of film. He took it on a tour of the vaudeville circuit and delighted audiences by being able to ‘interact’ with Gertie. Gertie is considered by many as the first true animated character to be featured in a film.

"Much of what he achieved was simply lost: like a rocket exploding brilliantly in the midnight sky, his work illuminated the medium for a breathtaking instant and then faded into virtual oblivion as, one by one, the scintillating spangles of his achievements winked out, leaving his colleagues as much in the dark as before. He was so far ahead of his time that many of his innovations were beyond the abilities of his contemporaries: what he had discovered and demonstrated about the capacities of each medium had to be re-discovered decades later by the next generation of cartoonists."by R.C Harvey

Happy Birthday to Victoria Vetri

Victoria turns 65 today. She had a career doing bit parts in 1960’s TV including Batman and Star Trek (Isis the cat), before becoming playmate of the year (1968) for Playboy magazine. This lead to her starring role in When Dinosaurs Ruled the Earth.

She also had a small role in Rosemary’s Baby under her stage name of Andrea Dorian taken from the ill-fated ship, Andrea Doria.

First Evolutionary Branching for Bilateral Animals

Assessing the root of bilaterian animals with scalable phylogenomic methods. 2009. A. Hejnol, et al. Proc. Royal Soc. B. Published online before print September 16, 2009.

Kamandi © DC Comics

Researchers have determined that the flatworm group Acoelomorpha is a product of the deepest split within the bilateral creatures — multicelled organisms that, like humans, have symmetrical body forms.

The worm is “as distant as an animal can be in bilateria and still be a bilaterian,” said Dunn.

Anchiornis huxleyi: New Feathered Theropod Older than Archaeopteryx

Now this is news!

A pre-Archaeopteryx troodondid theropod from China with long feathers on its metatarsus. 2009. Dongyu Hu, et al. Nature 461: 640-643. [DOI is not active yet, so check out Nature]

Anchiornis huxleyi

Abstract: The early evolution of the major groups of derived non-avialan theropods is still not well understood, mainly because of their poor fossil record in the Jurassic. A well-known result of this problem is the ‘temporal paradox’ argument that is sometimes made against the theropod hypothesis of avian origins. Here we report on an exceptionally well-preserved small theropod specimen collected from the earliest Late Jurassic Tiaojishan Formation of western Liaoning, China.

The specimen is referable to the Troodontidae, which are among the theropods most closely related to birds. This new find refutes the ‘temporal paradox’ and provides significant information on the temporal framework of theropod divergence.

Furthermore, the extensive feathering of this specimen, particularly the attachment of long pennaceous feathers to the pes, sheds new light on the early evolution of feathers and demonstrates the complex distribution of skeletal and integumentary features close to the dinosaur–bird transition.

Read the story at The New Scientist


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They Might Be Giants: Science Is Real

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A few weeks ago I linked to this video by They Might Be Giants. Their new cd,& DVD of kid-friendly songs about science, Here Comes Science, is out now. link

Born This Day (1922): Bert I. Gordon

Gordon was a movie producer of low, low budget films known for having great posters that sold the film. These films were fodder for many episodes of Mystery Science Theater 3000. He takes a bow here for “King Dinosaur”

New Starting Date For Quaternary

Doom Patrol © DC Comics

Controversy over when exactly the Quaternary Period began has raged for decades, with attempts in 1948 and 1983 to define the era. In 1983 the boundary was fixed at 1.8 million years, a decision which sparked argument within the earth science community as this point was not a 'natural boundary' and had no particular geological significance.

For practical reasons such boundaries should ideally be made as easy as possible to identify all around the world. The new boundary of 2.6 million years is just that," concluded Gibbard, "hence we are delighted at finally achieving our goal of removing the boundary to this earlier point."

The decision has been made by the International Commission on Stratigraphy (ICS), the authority for geological science which has acted to end decades of controversy by formally declaring when the Quaternary Period, which covers both the ice age and moment early man first started to use tools, began.

"It has long been agreed that the boundary of the Quaternary Period should be placed at the first sign of global climate cooling," said Professor Philip Gibbard. "What we have achieved is the definition of the boundary of the Quaternary to an internationally recognised and fixed point that represents a natural event, the beginning of the ice ages on a global scale." link

Kong By Powers

I missed this posting over at Atomic Surgery about the legendary SF artist Richard Powers illustrating King Kong.

Died This Say: William Diller Matthew

Feb. 19, 1871 – Sept. 24, 1930

Matthew was a superb mammalian paleontologist and important biogeographic theorist, and also G. G. Simpson's primary mentor. Matthew published voluminiously on the fossil record of mammals and advocated a fully modern approach to taxonomy that emphasized tying scientific names to natural biological populations. His 1930 paper gives a clear statement of this position.

Matthew's key biogeographic theory was that waves of faunal migration repeatedly went from the northern continents southwards. This theory, which had obvious racial and political overtones, was justified by a "stabilist" view of paleogeography (i.e., that the continents had never moved from their modern positions), and by evidence from the relatively young fossil record of mammals, at the expense of other data that would have shown the more ancient interconnections among South America, Africa, India, and Australia. Remarkably, Matthew remained a Darwinian despite working for the autocratic orthogeneticist H. F. Osborn for three decades.

Info from HERE. Image from HERE.

Frenchman Formation Terrestrial Ecosystem Conference Abstracts Now Available

For those of you who missed the conference, The Royal Saskatchewan Museum Contributions to Science No. 12, Frenchman Formation Terrestrial Ecosystem Conference, Program and Abstracts is now available by contacting the RSM Associates at rsm.associates@gov.sk.ca.

This sells for $15.95 Cdn (shipping and taxes extra).

Other great publications on Saskatchewan vertebrate paleontology are available here.

Raptorex: Little Big Rex

Tyrannosaurid Skeletal Design First Evolved at Small Body Size. P.C.Sereno, et al., early online edition of Science, Sept. 17, 2009.

Drawing by Todd Marshall

A 9-foot dinosaur from northeastern China had evolved all the hallmark anatomical features of Tyrannosaurus rex at least 125 million years ago.

Raptorex displays all the hallmarks of its famous descendant, Tyrannosaurus rex, including a large head compared to its torso, tiny arms and lanky feet well-suited for running. The Raptorex brain cast also displayed enlarged olfactory bulbs—as in T. rex—indicating a highly developed sense of smell.

"It's really stolen from tyrannosaurids all the fire of the group," Sereno said. All that Raptorex left for its descendants is "a suite of detailed features largely related to getting bigger."

Sereno marvels at the scalability of the tyrannosaur body type, which when sized up 90 million years ago completely dominated the predatory eco-niche in both Asia and North America until the great extinction 65 million years ago at the end of the Cretaceous Period.

"On other continents like Africa, you have as many as three large predators living in the same areas that split among them the job of eating meat," he said. But in Africa, the allosaurs never went extinct, as they did in North America, possibly presenting an evolutionary opportunity for Raptorex. "We have no evidence that it was a competitive takeover," said Sereno, "because we have never found large tyrannosaurs and allosaurs together."

Henry Kriegstein, a private fossil collector, brought the nearly complete Raptorex skeleton to Sereno's attention after buying it from a vendor. After Sereno and colleagues finish a more detailed study of Raptorex, it will be returned to a museum in Inner Mongolia, the place where the fossil was illicitly excavated. link

The Evolution of The First Fowers

Seed fertilization, development, and germination in Hydatellaceae (Nymphaeales): Implications for endosperm evolution in early angiosperms. 2009. P.J.Rudall, et al. American Journal of Botany, First published online August 13, 2009.

How did flowering plants evolved from the nonflowering gymnosperms?

New work on Trithuria, a genus in the plant family Hydatellaceae, thought to be one of the earliest families of angiosperms, suggests that double fertilization occurs. Double fertilization is a unique feature of flowering plants where one sperm nucleus unites with the egg, producing the embryo, while another sperm nucleus unites with a separate nucleus from the female, producing the endosperm. The endosperm is divided into two regions—the micropylar and chalazal regions.

In Trithuria, the cells of the micropylar region divide many times to form the multi-celled endosperm. However, the chalazal region forms a single-celled haustorium, a structure that absorbs nutrients and ultimately degenerates to form an empty space in the seed. This situation is broadly similar to that of some waterlilies and some monocots but differs from that of many other early-diverging angiosperms such as Amborella, in which the endosperm is formed from the chalazal region.

One of the current hypotheses is that the endosperm originated as a monstrous proembryo that fails to develop into a plant. Rudall and colleagues' observations support this theory.

Anatomical Record Dino Articles Now Available For Free Download

All of the articles from The Anatomical Record (Volume 292 Issue 9 (Sept. 2009) Special Issue: Unearthing the Anatomy of Dinosaurs: New Insights Into Their Functional Morphology and Paleobiology, edited by Peter Dodson) listed here are available from the publisher for free download HERE.

Many thanks to the publisher and editor for putting this issue togather and for making these articles available!

Samson Up For Auction

Unfortunate news: “Samson”, the T. rex goes for auction in Vegas on Oct. 3, 2009. The sad details are here.

When I came back from the gobi the glossy brochure for the auction was in my in-box. It features an article by Peter Larson on the specimen. The auction also features an Edmontosaurus from Black Hills and a composite Einiosaurus from Canada Fossils.