Archive for September, 2011

The actual 1861, two-paragraph article with the single, controversial sentence pulled out that names Archaeopteryx lithographica.

It was 150 years ago today, on 30 September 1861, that Hermann von Meyer gave the name Archaeopteryx lithographica to the feathered animal that fluttered over the Solnhofen lagoon in Late Jurassic Bavaria. At right is the entire published article…a scant two paragraphs, only one of which is devoted to Archaeopteryx. In that one paragraph he announced the discovery of a feathered skeleton, to go along with the isolated feather that he had announced six weeks earlier. For decades later, scholars argued over his key statement: “For the denomination of the animal I consider the term Archaeopteryx lithographica as appropriate” (the original German sentence is pulled out in the illustration). He named the animal, but not a specimen. Modern rules dictate the designation of a “holotype” specimen that officially bears the name. Should it be the feather, the skeleton, or neither? I discussed this debate a little in my first Archaeopteryx sesquicentennial post, but the result has been that the skeleton—now known as the London Specimen (BMNH 37001)—is the holotype. Happy 150th Birthday, Archaeopteryx! To celebrate, WitmerLab is launching today a website with five sets of interactive 3D PDFs of skull or skull parts of three Archaeopteryx specimens, including the one von Meyer announced 150 years ago today. It’s all open access and freely downloadable!

The skull of the Eichstätt Archaeopteryx (JM 2257), based on microCT scanning of a high-resolution cast made by Peter Wellnhofer for Witmer.


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The ankylosaurid armored dinosaur Euoplocephalus (AMNH 5405). A new article confirms the highly tortuous “crazy-straw” nasal passage coiled up within the snout..

In 2008, Ryan Ridgely and I published an article on dinosaur sinuses and nasal cavities in the Anatomical Record. One of our findings was unexpected to the point of seeming almost dubious. We found that, despite what had been stated in the literature, including my own published statements, armored dinosaurs (the plant-eating, tank-like ankylosaurs) didn’t have extensive paranasal air sinuses, but instead, long tortuous nasal airways. We looked at several skulls of both the ankylosaurid Euoplocephalus and the nodosaurid Panoplosaurus (or Edmontonia…someone needs to sort that out). According to our CT-scan-based analyses, the nasal passages took a long, twisting, looping course through the snout from the nostril to the throat. No one had ever suspected such a thing, and so we wondered what the community would think of our crazy crazy-straw hypothesis. Science is all about repeatability: if a claim is true, independent workers should be able to replicate results using the same or similar data. So, it was with no small amount of excitement/fear/anxiety that we greeted the news that an independent group consisting of respected researchers from the University of Alberta (Tetsuto Miyashita, ankylosaur specialist Victoria Arbour, and Philip Currie) were testing our hypothesis based on not only our own data but also data from additional specimens. Having others check our work was the reason we had freely released our original data to the community in 2008. That said, “promoting scientific repeatability” is a much more noble concept in the abstract (gulp!). Today, the results appear in an article in the Journal of Anatomy. (more…)

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