Chapter 5 Dinos Flashcards
Second major group of ornithischian cerapodans and their two subgroups
Marginocephalia
Pachycephalossuria bone heads
Ceratopsia horned Dino’s
Distinguishing feature of marginocephalia
Rim of bone protruding from back of skull to shield neck
How come pachycephalosauria are not well known
Solely known from bowling ball like heads resistant to break down
Identifying feature of pachycephalosaurs
Thickened skull bones with knobby protuberances
What did first bones of pachycephalosaurs identify as
How did they figure out it wasn’t
Kneecaps of bigger dinosaurs
Features of crania
They used computer modeling to determine biomechanical performance of domes a process called ?
Finite element modeling
Our results show that the skulls were ?
Not suited to resist loads from the side but nearly ideal for dealing with blows head on
Distinctive feature of ceratopsians
Beak shaped like that of a parrot rostral bone
Psittacosaurs , earliest ?
Parrot lizard
Ceratopsians
Five foot long bipedal quadrupedal
What did psitt’s not have that descendants had
What did they have to mill tough plants
No neck drill no horns not detentions to mince food
Gastroliths
Psitts are very numerous and what has been collected from them
Growth series (specimens representing all ages)
What are the 6.4 inch bristles on pitt’s equivalent to
Feathers and that all dinosaurs may have had some form of feather like structures
What did they find about life cycle of psitts
First growth curve took long time to reach adulthood (10 years)
Growth rates above reptiles and similar to slower growing mammals
Late Cretaceous period ceratopsians called what and earliest ones are
Neoceratopsians
Protoceratopsids
What is the most famous early neoceratopsian
Protoceratops
