Dinosaurs and Flight Theories

Question 1

Twhat does dinosaur mean?

Answer 1

terrible lizard

Question 2

what kind of group are dinosauria?

Answer 2

a monophyletic group that includes birds

Question 3

what are the 3 main of dinosaur groups and how are pterosaurs related?

Answer 3

pterosaurs are the outgroup
the 3 groups are
- ornithischia
- sauropodmorpha
- theropoda

Question 4

what are some characteristics of the ornithischia group

Answer 4

• quadpedal and bipedal
• herbviores
• small to large

Question 5

what are some characteristics of the sauropodmorpha

Answer 5

• quadrupedal
• long necks
• herbivores
• largest dinosaurs

Question 6

what are some characteristics of the theropoda

Answer 6

• bipedal
• carnivores
• ziphodont teeth (knife)
• had a fulcra
• includes aves

Question 7

what was the major synapmorphy with dinosaurs and how did that affect their agility?

Answer 7

they have an open actetabulum which allowed longer bones to attach and allowed the pelvic girdle to support much more weight

Question 8

how can we determine the blood pressure of dinosaurs?

Answer 8

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

Question 9

why is it presumed that that dinosaurs were endotherms?

Answer 9

• 4 chambered heart
• incubate their eggs
  -they were bipedal and had similar bone growth and isotopic ratio as mammals and birds

Question 10

how were dinosaurs able to get so big?

Answer 10

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

Question 11

what does the diet tell you about the population of the Dinos at the time?

Answer 11

most likely more ornithichia and sauropodmophra than therapodas

Question 12

describe the physical characteristics of ornthischia examples

Answer 12

spikes and plating
ex. stegosaurus, pachyesaurs

Question 13

what did they think they used this armour, specfically on their head for?

Answer 13

to butt each other for food or mates just like rams

Question 14

how much did magnitude did sauropdomorpha grow?

Answer 14

about 5 orders of magnitude

Question 15

what was the connection between long neck and long reach

Answer 15

long necks with light heads help with feeding on vegetation and the weight of their neck wasn’t too much due to pnematized bone

Question 16

since sauropodmorpha were homodonts, what does that tell you about their digestion

Answer 16

that it is mostly chemical instead of mechanical since a high fibrous diet

Question 17

what evolutionary pressure does having small young create when being large is your main defence

Answer 17

must have many to increase odds of survival

Question 18

what are some characteristics for therapods that made them different than the other dinosaurs

Answer 18

they had fulcra (wishbone) just like birds

Question 19

why were theropods so fast

Answer 19

their stride length was very big

Question 20

what are other ways theropods moved?

Answer 20

gliding so they can live in the trees

Question 21

why were theropods able to increase brain size?

Answer 21

they walked bipedal so the mass did not affect the balance as much

Question 22

why was thermal regulation easy for sauropods?

Answer 22

because the surface area was not as large as their volume so they didn’t loose heat as quickly

Question 23

how do we know that theropods laid eggs in pairs?

Answer 23

they have 2 oviducts and 2 ovaries and it developed at the same time

Question 24

what did changing as you grew allow in theropods

Answer 24

to occupy many different niches as you grew so the resources in one environment wouldn’t be limited

Question 25

what are the 3 feather hypothesis

Answer 25

• insulation
• sexual selection hypothesis
• sensory structure hypothesis

Question 26

explain the insulation hypothesis

Answer 26

early feathers were physically made to trap heat but they weren’t everywhere so people say its not true

Question 27

explain the sexual selection hypothesis

Answer 27

early feathers didn’t vary in colour and shape so this would be hard to explain

Question 28

explain the sensory structure hypothesis

Answer 28

filoplumes are connected to the base of feathers and connect to sensory cells and would work like whiskers
but the inital pynofiber and feathers we short and often distributed outside the head

Question 29

what are the 3 flight hypothesis

Answer 29

• aboreal hypothesis
• cursorial hypothesis
• wing assisted incline running (WIAR)

Question 30

explain aboreal hypothesis

Answer 30

first by jumping then parachuting then gliding then flying

Question 31

explain cursorial

Answer 31

that fight started when they would jump for insects
con: they can’t use their claws and it would stop traction

Question 32

explain the WAIR

Answer 32

they used wings to help them move faster when they are running
con: seen with modern bird with already developed wings