Dinosaurs and Flight Theories Flashcards
Twhat does dinosaur mean?
terrible lizard
what kind of group are dinosauria?
a monophyletic group that includes birds
what are the 3 main of dinosaur groups and how are pterosaurs related?
pterosaurs are the outgroup
the 3 groups are
- ornithischia
- sauropodmorpha
- theropoda
what are some characteristics of the ornithischia group
- quadpedal and bipedal
- herbviores
- small to large
what are some characteristics of the sauropodmorpha
- quadrupedal
- long necks
- herbivores
- largest dinosaurs
what are some characteristics of the theropoda
- bipedal
- carnivores
- ziphodont teeth (knife)
- had a fulcra
- includes aves
what was the major synapmorphy with dinosaurs and how did that affect their agility?
they have an open actetabulum which allowed longer bones to attach and allowed the pelvic girdle to support much more weight
how can we determine the blood pressure of dinosaurs?
we can figure the required pressure form figuring out the distance form the highest point to the heart and check their femoral foramen to see the diameter to the artery
why is it presumed that that dinosaurs were endotherms?
- 4 chambered heart
- incubate their eggs
-they were bipedal and had similar bone growth and isotopic ratio as mammals and birds
how were dinosaurs able to get so big?
factors that allowed them to grow
- efficient respiration
- pneutized bones
- efficient reproduction
factors that caused them to grow
- abundant food due to lots of CO2 in the air
- predators wanted larger prey which made the predators larger and vice versa
what does the diet tell you about the population of the Dinos at the time?
most likely more ornithichia and sauropodmophra than therapodas
describe the physical characteristics of ornthischia examples
spikes and plating
ex. stegosaurus, pachyesaurs
what did they think they used this armour, specfically on their head for?
to butt each other for food or mates just like rams
how much did magnitude did sauropdomorpha grow?
about 5 orders of magnitude
what was the connection between long neck and long reach
long necks with light heads help with feeding on vegetation and the weight of their neck wasn’t too much due to pnematized bone
since sauropodmorpha were homodonts, what does that tell you about their digestion
that it is mostly chemical instead of mechanical since a high fibrous diet
what evolutionary pressure does having small young create when being large is your main defence
must have many to increase odds of survival
what are some characteristics for therapods that made them different than the other dinosaurs
they had fulcra (wishbone) just like birds
why were theropods so fast
their stride length was very big
what are other ways theropods moved?
gliding so they can live in the trees
why were theropods able to increase brain size?
they walked bipedal so the mass did not affect the balance as much
why was thermal regulation easy for sauropods?
because the surface area was not as large as their volume so they didn’t loose heat as quickly
how do we know that theropods laid eggs in pairs?
they have 2 oviducts and 2 ovaries and it developed at the same time
what did changing as you grew allow in theropods
to occupy many different niches as you grew so the resources in one environment wouldn’t be limited
