Summary: TEHRAN (FNA)- Auroraceratops, a bipedal dinosaur
that lived roughly 115 million years ago, has been newly described by paleontologists.
It has even been proposed that, due to functional convergence, mammals might be a better system to study bipedal dinosaur
locomotion (Carrano, 1998; Carrano & Biewener, 1999).
The famous Tyrannosaurus rex is one example of a bipedal dinosaur
, as is the velociraptor.
They likely belonged to a Torvosaurus, a massive, bipedal dinosaur
that grew up to 36 feet tall.
"Like other maniraptoran theropods, this would have been a small, feathered, bird-like bipedal dinosaur
with a fairly short tail, long neck, long slim hind legs, and feathered clawed forelimbs," he added.
Fossil handprints made by a crouching theropod (artist's depiction,) reveal that this meat-eating bipedal dinosaur
had palms that always faced inward, suggesting theropods abandoned the use of their forelimbs as legs early in their evolution.
Hip height of bipedal trackmakers can be estimated using morphometric ratios derived from measurements of bipedal dinosaur
skeletons (Alexander 1976; Thulborn 1989).
Fifteen of the fossils were Limusaurus inextricabilis, an odd bipedal dinosaur
with short arms and a beak.
Because the imprints immortalized only a short portion of the creature's dash, it remains unclear just how long a large, bipedal dinosaur
could sustain a sprint.
However, analysis shows that the fake fossil's tail came from Microraptor zhaoianus, a small bipedal dinosaur
first described by Chinese scientists in the December 7, 2000 NATURE.
On the other hand, Jones says, Caudipteryx has a very short tail--possibly shorter than that of any bipedal dinosaur
. As a result, the animal's center of gravity was located forward of the hips, a typical body structure of flightless birds, he notes.
"Being limited to walking speeds contradicts arguments of high-speed pursuit predation for the largest bipedal dinosaurs