Chordates III (Birds, Mammals) Flashcards
What kind of beak do Phylum Chordata, Subphylum Vertebrata, Class Aves have?
Keratinized (keratin=protein) beak lacking teeth highly adapted to food habits
What kind of feathers do Phylum Chordata, Subphylum Vertebrata, Class Aves have?
Feathers adapted for flight
- Forelimbs modified into wings with keratinized feathers
- Modified Bones
- Modified Lungs
Are Phylum Chordata, Subphylum Vertebrata, Class Aves oviparous or viviparous?
Oviparous with parental care
From whom do birds descend from?
Archosaurian reptiles
- Theropod dinosaurs (velociraptors) are sister
- Earliest known sister group w/ feathers are Archaeopteryx
What internal modifications have birds undergone?
Skeletal Modifications
Lung Modifications
Gut Modifications
Excretory Modifications
What skeletal modifications have birds undergone?
- Bones with struts
- Rigid airframe w/ fused vertebrae
- Sternum w/ large keel to support breast muscle for flight
- Muscles reduced in legs, mostly ligaments
What Lung Modifications have birds undergone?
- More efficient respiration
- Air passes across parabronchi
- Less dead volume
What Gut Modifications have birds undergone?
- Muscular crop and gizzard
- Use of sand for grinding foods
- Very rapid digestion and elimination
What Excretory Modifications have birds undergone?
- More efficient kidney
- Concentrated Uric Acid
- Kidney empties into cloaca
- Salt Glands allow drinking of seawater
What is the cloaca?
“Sewer”
- Kidneys deposit metabolic waste in rectum
- Cloaca serves multiple functions (poop/pee)
What is the Salt Gland?
Allows birds to drink seawater b/c they can get rid of salt from seawater by crying salty tears
How do female birds reproduce?
Only left ovary and oviduct develop
-Poop egg out of cloaca
How do Male birds reproduce?
Most have lost penis - “cloacal kissing”
-Ducks/Ostrich have explosive cork-screw penis
What is brood parasitism?
Bird lays egg in another birds nest for other bird to raise
How do birds migrate?
Seasonal migration
- same/different routes
- nonstop or rest
Navigate using:
- visual cue
- sun during day and north star at night
What are the two defining characteristics of Mammals?
Hair and Mammary Glands
What three lines of mammals survived the Mesozoic era?
Monotremes (egg laying mammal), Marsupials, and Placentals
What are the features of hair in Mammals?
Made mostly of Keratin
- Common to ALL mammals
- Many functions (Warm, tactile, defense)
What are integument glands in Mammals?
Sweat Glands
-cooling and sweat
Sebaceous Glands
-oil for skin and hair
What are Mammary Glands in Mammals?
Modified sweat glands
- fully develop in mature females
- give milk during lactation
- no nipples in monotremes
How is the modification of teeth, jaw, and skull significant in mammals?
Reflect feeding specialization
- incisors, canines, molars
- Sharp canines/incisors for shearing meat (carnivores)
- Large/many molars for grinding (herbivores)
How do herbivores (like cows) get nutrition from plants?
- Molars for grinding
- Multiple stomachs w/ symbionts
- Takes a long time to draw out nutrients from plants so long passage through multiple stomachs for bacteria to draw out nutrients
What is Diphyodont?
2 sets of teeth (deciduous and permanent)
What kind of modification of integument or skeleton do mammals experience?
Horns - keratin over skull bone
Antlers - annual bone growth and loss
What kind of reproductive features do mammals exhibit?
- Dioecious
- Internal fertilization
- Most with specific breeding season
- Fertility restricted to periods of estrus
What kind of reproductive features do monotremes exhibit?
Oviparous
- platypus eggs in burrow
- echidna eggs in pouch
What kind of reproductive features do marsupials exhibit?
Viviparous
- short gestation
- newborns must attach to nipple in pouch
What kind of reproductive features do placentals exhibit?
Viviparous with placenta
- long gestation
- gestation in uterous with nourishment from placenta
- Developmental status varies (precocial vs atricial)
From what kinds of lifestyle did Homo sapiens evolve from?
Arboreal (tree living) to ground dwelling (require bipedalism)
What adaptations do hominids exhibit?
- Bipedalism
- Grasping hands, opposable thumb
- Complex social behavior
- tool use
What complex social behaviors do hominids exhibit?
grooming, territoriality, parental care, kin groups
