L4: Ornithischian Dinosaurs Flashcards
What is the pelvic structure of the saurischian dinosaur?
Is ‘dinosaur hip’, with the pubis bone directed anteriorly and downward, like a lizard
What is the pelvic structure of the ornithischian dinosaur
Is ‘bird hip’, with the pubis running posterior to the ischium, opisthopubic condition
What is the fundemental division among dinosaurs?
Pelvis structures, were either ornithischian or saurischian
What kind of dinosaurs are in the Ornithischian?
Armoured, horned and duck billed
What groups of ornithischia were studied?
Stegosauria Anklyosaurs Pachycephalosaurs Certopsia Ornithopods
How many species of stegosaurus were there?
12
When did stegosaurus range from and till?
Middle jurassic to early cretaceous
What was the general size of stegosaurus?
3-9m
How much did stegosaurus weigh?
300-1500kg
What is the striking feature identifying the stegosaurus?
have rows of special bones called osteoderms, which develop into spines and plates along the neck, back and tail.
What size brain do stegosaurs have?
relatively small brains, about 0.001% of the body mass - lifestyle doesn’t require a large brain
How were stegosaurus distributed?
Appear to be spread widely, a cosmopolitan species
What does the body plan of stegosaur indicate about its lifestyle?
inclined toward plodding and not sprinting as large and bulky
Teeth and large abdominal region suggest herbivorous lifestyle
How did stegosaurus protect itself from predators?
Due to its size, spines and large heavy tails, stegosaurus was relatively safe from predators, only the young would be at risk
What is known about the sociality of stegosaurus?
Little is known about stegosaurus behaviour, as there are not many full specimens to illustrate this, do see some degree of sexual dimorphism in rib structure
What function do the spines on stegosaurus have?
Maybe for protection, but also likely they were used for heat regulations there are indications of a very good blood supply
What size was Ankylosaur?
generally 5m long
How many species of ankylosaur were there?
30
What similarities did ankylosaur have to stegosaurus?
Forelimbs shorter than hind limb
What was characteristic about the ankylosaur?
Are encased in shell like dermal armour, that forms a shield across the body
How much did the ankylosaur generally weigh?
Weigh up to 3500kg
What does stegosaurus feed on?
Feed on plants with a beak
Where and in what state are ankylosaurus fossils discovered?
Often deposited along the sea shore or even in rocks representing open marine environments. Often found upside down, likely because of their heavy armour
How did ankylosaurus defend itself?
Would not be able to travel fast so defence came from its armour. Had very strong shoulder muscles, and this could have aided in the use of its tail, which terminates in a club
