Defining Dinosauria

Owen and Dinornis 1879

Richard Owen poses next to a Dinornis (moa) skeleton in 1879—but is it a dinosaur?

This group, which includes at least three well-established genera of Saurians, is characterized by a large sacrum composed of five anchylosed vertebrae of unusual construction, by the height and breadth and outward sculpturing of the neutral arch of the dorsal vertebrae, but the twofold articulation of the ribs to the vertebrae, viz. at the anterior part of the spine by a head and tubercle, and along the rest of the trunk by a tubercle attached to the transverse process only; by broad and sometimes complicated coracoids and long and slender clavicles, whereby Crocodilian characters of the vertebral organs also exhibit the same transitional or annectent characters in a greater or less degree. The bones of the extremities are of large proportional size, for Saurians; they are provided with large medullary cavities, and with well developed and unusual processes, and are terminated by metacarpal, metatarsal and phalangeal bones, which, with the exception of the ungual phalanges, more or less resemble those of the heavy pachydermal Mammals, and attest, with the hollow long-bones, the terrestrial habits of the species.

That’s how, in 1842, Richard Owen described “a distinct tribe or sub-order of Saurian Reptiles, for which I would propose the name of Dinosauria“, a group of organisms which needs no further introduction. But what, 170 years later, can be properly classified as a dinosaur? Former highschool science teacher Brian Thomas thinks he knows better than today’s scientists. He wrote on Wednesday, in “Four-Winged Dinosaur Definition Doesn’t Fly“: Continue reading

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The Domesticated Red Junglefowl

A Red JunglefowlA new YOM post asks “which came first, the chicken or the egg?”

This age-old question really has a simple answer. However, attempts to answer it and to get around implications of the simple answer are often quite convoluted.

Yes, there is an answer: the egg was first, because there have been animals laying eggs for longer than there have been chickens. It’s simple, at least so long as you don’t specify that it must be a chicken egg. But for reasons that have been rather poorly thought out, the ICR insists the opposite was the case: Continue reading

Microraptor

For Wednesday’s DpSU we have Is New Fossil a Bird-Eating Dinosaur? Brian Thomas has a wonderful habit of randomly disagreeing with palaeontologists about the classification of various bird-like dinosaurs. If you believe him, you’ll think that Caudipteryx has no feathers, that Balaur is not bird-like at all, and now that Microraptor is a true bird (and also, not a dinosaur).

The holotype of Microraptor gui Continue reading

Dinosaurs! (Flood Part #2)

Arguably the most entertaining part of any creationist Global Flood model is where the dinosaurs come in to it. Indeed, as John Morris himself asks for our introductory article, How Do The Dinosaurs Fit In? Let’s find out…

Velociraptor mongoliensis

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