Lecture 1 Flashcards
What makes a bird a vertebrate?
They have vertebrae/spinal column that form around the notochord and nerve chord
What makes a bird a tetrapod?
They have 4 limbs, pentadactyl limbs
What makes a bird an amniote?
The most recent common ancestor hatched from an amniotic egg
Features of an ambiotic egg are:
Protective shell and the yolk sac that provides nutrients and lipids to the embryo
What make a bird an archosaur?
Antorbital fenestrae and mandibular fenestrae
What makes a bird a theropod? (name 5?)
- elongate mobile s shaped necks
- digitigrade posture
- tridactyl foot
- ankle forms between tarsal bones
- hollow pneumatic bones
- furcula
- fused bony sternum
- feathers
What major event wiped out the relatives of modern birds?
Mass extinction in the cretaceous-paleogene boundary
What are the 3 major innovations of birds?
Powered flight, pygostyle and alula
What taxon is related to powered flight?
Archaeopteryx
What taxon is related to the pygostyle?
Confuciusornis sanctus
What taxon is related to the alula?
Pigeon??
What are features of enantiornithes?
- y shaped furcula, long hypocleideum
- teeth
- concave-convex scapula coracoid joint
What are features of hesperornithes?
- reduced non functional wings
- robust elongate legs
What are the two main groups of neornithes?
paleognathae and neognathae
What is the alula important for?
increases manoeverability
