EEB 2214 (BIOLOGY; ZOOLOGY) EXAM 3 QUESTIONS AND ANSWERS ELABORATIONS BASED ON LECTURES 17-25 17,18,19,20,21,22 23,24,25

EEB 2214 (BIOLOGY; ZOOLOGY) EXAM 3 QUESTIONS AND
ANSWERS ELABORATIONS BASED ON LECTURES 17-25
17,18,19,20,21,22 23,24,25
true or false: adaptations evolved in dinosaurs for functions other than flight
Answers :true
true or false: birds are dinosaurs


Answers :true
What do we refer to as our classic dinosaurs?


Answers :Non-avian dinosaurs
true or false: non-avian dinosaurs had feathers


Answers :false; had feather-like structure called proto-feathers
When did bird divergence occur?


Answers :during the late Jurassic
what evolved first proto feathers or flight


Answers :proto-feathers
what are the 3 distinctive features of extant birds?


Answers :1. feathers
2. perfcula
3. extensive pneumatization of post-cranial skeleton
percula

,Answers :wishbone; fusion of clavicles
pneumatization


Answers :The formation of air cavities, hollow bones
What feature made pterosaurs and dinosaurs distinct?


Answers :triangular fenestra
What group did birds descend from?


Answers :Therapod dinosaurs
what is the closest relative of birds and who they are descended from?


Answers :Dromeosaurs
What type of diet is the ancestral condition for birds


Answers :carnivorous
true or false: birds have always been bipedal


Answers :true
What bird feature is important for thrust?


Answers :asymmetric wing feathers
What features are seen in extinct dinosaur ancestors that are similar to birds?

,Answers :bipedalism, long arms, furcula, pneumatized skeleton, feathers
Characteristics of Dromaeosaurs


Answers :-bipedal, active predators
-shorter forelimbs and some elongated forelimbs
-fruit and seed-eating traits in advanced birds
why is leaf-eating rare in birds?


Answers :(indicates ancestral) adaptations needed to consume leaves are not well-
suited for flight
-need large stomache
-metabolism is slow
-teeth
-large body size
Describe the bone structure of dromaeosaurs


Answers :Pubic bone: pointed back toward the ischium, no pre-pubic process


Neck: s-shaped
true or false: dromaoesaurs have a pre-pubic process


Answers :false
shared skeletal features between modern and ancestral birds


Answers :-neck bends in S-shape
-pelvic structure (pubis and ischium face opp. direction, pubis is forward)

, -
what is the benefit of an s-shaped neck


Answers :can hold neck upright so can look around when walking


can lengthen the neck to catch prey
What is the benefit of walking on toes?


Answers :they are quicker and quieter because their mass is higher up, less surface
area in contact with the ground
Why is the knee of modern birds higher up?


Answers :because they walk on their toes
Why do modern birds have larger sternums?


Answers :to support enlarged flight muscles
what was the purpose of long, stiff tails in early birds


Answers :had short and longer tail feathers


better aerodynamics


frees up legs for movement and diversification
What adaptation occurred in birds to create a strong, immovable trunk stabilized
for flight