Vertebrates 4 Flashcards
(23 cards)
What group do the birds belong to?
The reptile group
Are reptiles monophyletic?
No they are not because they include birds
Ancestor of birds?
Theropod dinosaur
Shared characteristics between birds and the theropod?
-Bipedal(3 hind toe)
-Carnivorous
-4 chambered heart
Archaeopteryx
-Fossil
-Evolutionary cousin to birds
Characteristics of Birds
-Amniotes
-Endothermic
-4 chambered heart
-Most fly
-Feathers
-Diverse feet
-Diverse beaks(diverse diets)
What is an amniote?
An organism whose embryo develops in an amniotic egg
Things birds do well?
-Breathing
-Thermoregulation
Two main classes of organisms in which they regulate heat and how they differ?
Endotherms: Generate their own internal heat through metabolic processes
Ectotherms: absorb heat from the outside environment
Heterotherms vs Homeotherms
Heterotherms: Allow temperatures to fluctuate
Homeotherms: Keep their body at a constant temperature
How do ectotherms and endotherms control temperature? and metabolic processes?
Ectotherms: as temperature increase their metabolism increases
Endotherms: as temperature increases metabolic rate increases to get rid of heat, as temperature decrease metabolic rate increase to produce heat
Name the three mechanisms animals use to maintain body temperature?
- Behavioural
2.Physiological - Physical
How do animals thermoregulate behaviourally?
Animals make behavioral choices so that they can better regulate their body temperature(ex. If it’s too hot outside, humans go inside)
How do animals thermoregulate physiologically?
-Too hot: increase blood flow to periphery(loses heat), sweating(evaporative cooling), panting
-Too cold: decrease blood flow to periphery, shiver
How do animals thermoregulate physically?
-Insulation(fur, feathers, fat)(keeps heat inside and from diffusing out)
-Surface area:volume(colder=bigger)(hotter=smaller)
-color(changes how much solar radiation is entering the body)
Allen’s Rule
Rabbits in the north have short ears(don’t want long extremities that can get cold easily)
Rabbits in the south have long ears that allows them too be cooler
Why do birds need good respiration?
For flying and endothermy both processes require lots of oxygen
What is special about birds lungs?
-They have air sacs
-They don’t have tidal flow(air does not go in and out with every breath)
How do Birds respire?
Breath One:
Bird breathes in, air enters the posterior air sacs. Bird breathes out, air enters the lung.
Breath Two:
Bird breathes in, air enters the anterior air sac, bird breathes out and the air leaves the bird via the air sac.
How many times has flight evolved and in what groups?
-4 times
-Insects
-Birds
-Bats
-Pterosaurs
What adaptations make birds better at flying?
-Hollow bones
-Enlarged sternum and keeled(attached to the muscles that power the bird to fly)(larger=larger muscles)
-Feathers
What are the 4 functions of feathers? What are feathers made of? Skin of legs?
-insulation
-lining nests
-Flight
-Sensory structures
-B keratin derived from scales
-Birds have reptile like scaled skin on their legs
Did flight evolve from the ground up or the trees down?
Most evidence shows the ground up
