Lecture 20- Birds

Question 1

Characteristics of aves (5)

Answer 1

• homeothermic reptiles
• lightweight skeleton
• keratin beak, no teeth
• hindlimbs: walking, perching, swimming
• lay eggs

Question 2

What group did birds evolve from

Answer 2

Dromaeosurid Theropods eg. Velociraptor

Question 3

Major innovations in birds (3)

Answer 3

feathers, wings, flight

Question 4

Significance of Archaeopteryx

Answer 4

Early Jurassic bird: demonstrates transitional stage of birds from dinosaurs

Question 5

How did flight evolve (2)

Answer 5

1. Ground up: bipedal running and leaping in air (flapping stage)
2. Trees down: evolved from gliding ancestors who began to fall gliding structures (gliding stage)

Question 6

What do birds need for flight (3)

Answer 6

• light body
• power
• superb vision

Question 7

What adaptations do birds have for flight (4)

Answer 7

• Feathers
• Skeletal features
• Air sacs
• Keratinised beak

Question 8

Why do birds migrate (2)

Answer 8

• seasonal resources like food
• suitable breeding grounds

Question 9

Reproduction features of avians (3)

Answer 9

• internal fertilisation before egg
• no penis (copulation)
• parental care is shared (incubating eggs)