Birds Flashcards
What are the 2 major groups of birds?
The palaeognathae and the neognathae
How many species of bird are there?
Approx. 10,000
What is the palaeognathae composed of?
The ratites and the tinamiformes
The ratites are large and flightless. How is this shown in their skeleton.
They have no keel on their sternum.
What is the neognathae composed of?
The gallon serae and the neoaves.
What are the gallon serae?
Ducks and jungle fowl.
Which group contains 95% of bird diversity?
The neoaves
Archaeopteryx was the first bird sample. What features were theropod and which are avian?
Theropod = long pubis, caudal tail, teeth in the beak, claws
Avian = furculum, 3 digits, feathers
How many digits do birds have?
3
What is the pygostyle?
Fused caudal vertebrae for flight muscles and feather attachment.
What does the furculum do?
Strengthens the thoracic skeleton. It also stores energy on the downstroke of the wing which is released on the upstroke.
What is the syncosacrum?
The pelvis is fused to the vertebrae for stability in landing.
Why is a digigrade stance advantageous to birds?
It shifts their centre of gravity backwards.
What is the rachis?
The ventral, hollow vein in a feather.
What are the main types of feather?
Insulation, flight, contour and display.
Why are flight feathers asymmetrical?
So the flight vector does not flip the feather over on the downstroke.
What is unique about birds’ eyes?
They are so large that they dorso-laterally compress the brain and meet in the centre of the head.
What shape are birds’ eyes?
Tubular