Birds Flashcards
What class are birds in?
Aves.
What did birds evolve from?
Theropod dinosaurs.
When did true birds appear?
Cretaceous.
When did birds diversify?
Tertiary.
What are the two major bird clades?
Paleognathae and neognathae.
Give characteristics of Paleognathae.
No keel, flightless.
e.g. ostrich.
Give characteristics of Neognathae.
Flexible palate.
Possess carina/sternal keel.
Includes penguins.
What are the three main foot formations in passeriformes?
Anisodactyly - 3 forward, 1 back.
Zygodactyly - X shape.
Pamprodactyly - 4 forward.
What skull fenestration do birds have?
Diapsid.
What is a gizzard?
Muscular structure used to grind up and process food. Sometimes filled with pebbles birds eat to mechanically grind up food.
What is a toucan bill like?
Biocomposite beak, interior is rigid foam composed of bony fibres and the exterior is made of keratin.
What is a woodpecker bill like?
Spongy bone at the site of impact between the beak and skull as a cushion. Longer lower parts of mandibles direct force away from the brain.
Are birds ovi, ovovivi or viviparous?
Oviparous.
How can birds conserve heat?
Draw beak and feet into plumage.
Counter-current heat exchange, arteries going in and veins going out in close proximity recapture heat and save it.
Torpor or hibernation.
What is a bird’s circulatory system like?
4-chambered heart.
Larger body size:heart mass ratio compared to mammals.
What is a bird’s respiratory system like?
Unidirectional airflow.
Compare bird and reptile senses.
Reduction in smell in birds.
Expansion in optic lobes. - provide larger and sharper images.
Expansion of forebrain. .