Vertebrate Exam 3 Flashcards
What is the habitat and distribution of Class Aves?
Everywhere
Name the 7 Major Features of Aves.
- Four-Part Body
- Anterior limbs modified for flight
- Body covered with feathers
- Legs covered with scales
- Beak (jaw covered with sheath), no teeth.
- Endothermic and homeothermic
- Well-developed nervous system, including highly developed cerebellum
Name the Four-Part body of Aves.
Head, neck, body, and tail
What are the 7 adaptations of flight?
- Limitations to size
- Unique respiration
- Pneumatic Bone
- Skeleton
- Muscles
- Streamline body
- Integument
Flight Limitations on Size
Muscle Power
Larger birds have lower wing beat frequencies
Large birds require longer takeoff runs
Largest Extinct Flying Bird
Giant Condor
Largest Living Bird
Ostrich
Largest Extinct Non-flying Bird
Giant Elephant Bird
Bird Respiratory Cycle
1st Inhalation: ~75% of the air goes directly to posterior air sac
1st Expiration: Oxygenated air is shunted through lungs
2nd Inhalation: Deoxygenated air is passed onto anterior air sacs
2nd Expiration: Deoxygenated air exits
Bird Countercurrecnt exchange
Blood flow of capillaries is in the opposite direction to air flow
Functions of Bird Respiratory System
- Respiration with efficient unidirectional air flow
- Cooling: Air sac system helps cool the bird when flying
- Vocalization: syrinx at base of trachea where the two bronchi diverge
Bird Pneumatic Bones
extremely light but strong, contain air cavities
- -More developed in larger birds
- -Distribution varies, but usually in the skull
Sternum
Greatly enlarged bone that bears the keel (not in flightless), which allows for attachment of muscles in flight
Clavicle
Usually fused to form furcula (wishbone). Adds bracing for scapula
Bird Vertebral Column
Rigid. Most vertebrae (except neck) are fused together with the pelvic girdle to form stiff frame work for flight
Muscle Distribution of Strong Fliers
Flight muscles make up 25-35% of total body mass, little leg muscle
Muscle Distribution of Predatory Birds
Use legs to capture prey. Flight muscles may makeup 20% of total body mass and leg muscles 10%
Muscle Distribution of Swimming Birds
Roughly equal distribution of muscle. Muscles makes up 30-60% of mass.
Dark Meat
myoglobin with high capacity for aerobic metabolism (Breast in sustained fliers)
White Meat
Lack of myoglobin, more short distance fliers, little capacity for aerobic metabolism.
Specificity of Songs
Species specific and Learned Dialects varies.
Individual Variation: some distinguish their songs from neighbors to establish territory
ex: New World Flycatchers- song develops innately
White-crowned Sparrow: learn in first 50 days of life
Why do birds make calls?
Not a song, a response to stimuli.
Produced by both sexes in and out of breeding season
Alarm, feeding, flocking, aggression, agonistic
Bird Visual Displays
- Often associated with Songs
- Males are have brightly colored breeding plumage
- Cryptic color in ground birds
Streamlined body Shape
For speed: Passerines: Up to 50km/hr Ducks and Geese: 80-90 km/hr Peregrine falcons: 200 km/hr when diving Slow Fliers- Flamingos....
Bird Integument
Feathers: Modified reptilian epidermal scales
Biochem: Over 90% is beta-keration, 1% lipid, 8% water
Feathers may weigh more than skeleton
Arranged in tracts
Functions: flexible, strong flight surface, insulation, shed water, visual display
Crop
At lower end of esophagus (in many birds), serves as storage chamber
In some birds it produces milk by the breakdown of epithelial cells of the lining. Regurgitated by males and females for young, higher fat than cow’s milk
Gizzard
Lower part of the stomach lined with horny plates for grinding food. Some birds swallow coarse objects or pellets to help breakdown food