"It can now provide us with a better picture of the starting point for the changes between bipedal and quadrupedal ceratopsians
," adds Morschhauser.
This paper deals specifically with the issue of gait in ceratopsian
"If sexual selection is indeed the driver of ornament evolution in ceratopsians
, as we are increasingly confident it is, demonstrating it through different lines of evidence can provide a crucial window into tracing its effects over potentially huge timescales," Knapp added.
The length of the chord of the arc of the track is approximately 25 cm, which is approximately half the size of purported ceratopsian
manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops (Lockley and Hunt, 1995).
Johnson says that Torosaurs, Triceratops and probably all ceratopsian
dinosaurs had sprawling lizard-like forelimbs after all, and therefore could not gallop.
Rigby proposes that horns were arranged to protect against accidental injuries to the ceratopsian
frill -- a thin layer of bone sticking out from the back of the skull like a huge shield.
"It coexisted with two other groups of horned dinosaurs (ceratopsians
): centrosaurs and chasmosaurs.
Famous dinosaurs in that area included predatory tyrannosaurs, the duck-billed hadrosaurs, heavily armored ankylosaurs, and horned dinosaurs known as ceratopsians
. Crocodiles and turtles were also common.
The armored Stegosaurus is here, as well as the homed and frilled Ceratopsians
and a Pachycephalosaur with its huge helmet of bone.
Past studies suggest that horned dinosaurs such as Triceratops and their relatives, a group known as ceratopsians
, lived in herds and used the frills on their skulls and other ornamentations to identify members of their own species, as did many other dinosaurs (SN: 8/13/05, p.
In Alberta's Dinosaur Provincial Park, a bone bed of Centrosaurus --one of the ceratopsians
, horned dinosaurs--has been worked by Philip Currie and others from the Tyrrell Museum of Palaeontology.
Other quadrupedal dinosaurs like stegosaurs (Galton and Upchurch, 2004) or ceratopsians
(Dodson et al., 2004) have not been described yet (neither by osteological or ichnological remains) from the Aptian-Turonian of Europe, so we assume that these dinosaurs are not candidates to be the trackmakers of Parede.