Sunday, November 1, 2009

Dinosaur Growth May Wipe Out 1/3 of Species

Science Daily: New Analyses Of Dinosaur Growth May Wipe Out One-third Of Species.

ScienceDaily (Oct. 31, 2009) — Paleontologists from the University of California, Berkeley, and the Museum of the Rockies have wiped out two species of dome-headed dinosaur, one of them named three years ago -- with great fanfare -- after Hogwarts, the school attended by Harry Potter.

Their demise comes after a three-horned dinosaur, Torosaurus, was assigned to the dustbin of history last month at the Society of Vertebrate Paleontology meeting in the United Kingdom, the loss in recent years of quite a few duck-billed hadrosaurs and the probable disappearance of Nanotyrannus, a supposedly miniature Tyrannosaurus rex.

These dinosaurs were not separate species, as some paleontologists claim, but different growth stages of previously named dinosaurs, according to a new study. The confusion is traced to their bizarre head ornaments, ranging from shields and domes to horns and spikes, which changed dramatically with age and sexual maturity, making the heads of youngsters look very different from those of adults.

"Juveniles and adults of these dinosaurs look very, very different from adults, and literally may resemble a different species," said dinosaur expert Mark B. Goodwin, assistant director of UC Berkeley's Museum of Paleontology. "But some scientists are confusing morphological differences at different growth stages with characteristics that are taxonomically important. The result is an inflated number of dinosaurs in the late Cretaceous."


Quantum_Flux said...

Weired, none of the movies I've seen about T-rex showed it having horns.

Raptor Lewis said...

I'm well aware of such research and I must say that it's an intriguing hypothesis, though I'm not sure what I'm inclined to believe at this point. I wouldn't be surprised if this does mean that about 1/3 of all Dinosaur taxa didn't exist. It's a classic case of mistaken identity.

Raptor Lewis said...

I wasn't aware of Torosaurus being considered a useless genus! Hmm....what is it considered to be then?

Raptor Lewis said...

Quantum Flux- Actually, you are looking at the Pachycephalosaurid, Dracorex hogwartsia, though I'm not sure it will have that nomenclature much longer. The research shows that is just a juvenile Pachycephalosaurus. :)