Aves Flashcards
(67 cards)
1
Q
extant reptilia
A
- tuataras
- lizards
- snakes
- turtles
- crocodilians
- birds
2
Q
when did modern bird orders evolve
A
Cenozoic
3
Q
Archaeopteryx lithographica
A
- evolutionary link between non-avian reptiles and birds
- jaw with teeth instead of beak, claws on end of wings
- long bony tail
- could probably glide from perch to perch but could not do prolonged flapping flight
- open pelvic girdle to lay eggs
- keel sticks out in front of sternum
4
Q
Avian characteristics
A
- 10,000+ species as DNA reveals cryptic species
- feathers
- forelimbs modified as wings
- bones with air cavities–> lightweight
- long necks and many cervical(neck) vertebrae
- caudal(tail) vertebrae shortened to a pygostyle
- powerful muscles attached to a strong breastbone with a prominent keel
- no teeth, replaced with horny beak (keratin) and a grinding stomach(gizzard)
- all bird oviparous
- eggs with hard calcareous shell
- almost all birds make a nest to shelter eggs and often young
- birds are endothermic (maintain constant body temp by generating heat internally)
- lungs with parabronchi and a one-way air flow
- full separation of pulmonary and systemic blood circulation
- all birds uricotelic (excrete uric acid)
5
Q
gizzard
A
grinding stomach
6
Q
feathers
A
- solid surface for flying
- streamlining
- insulation
- water-repellant (but ducks make them water-proof with oil)
7
Q
contour feathers
A
- most feathers
- veined
- cover and streamline a bird’s body
- consists of hollow quill emerging from skin follicle
- shaft= continuation of quill, bears barbs
- barbs arranged in parallel fashion and spread diagonally outward from both sides of the central shaft to form a flat, expansive, webbed surface, the vane
- can be several hundred barbs in a vane
- numerous parallel filaments called barbules set in each side of the barb and spreading laterally from it
- barbule of one barb overlap the barbules of a neighboring barb in herringbone pattern and are held together by tiny hooks
- bird preen the feathers with their beaks to re-align the vane
8
Q
flight feathers
A
- contour feathers that extend beyond the body and are used in flight
9
Q
down feathers
A
- soft tufts
- beneath contour feathers
- soft because barbules don’t have hooks
- abundant on breast and abdomen of water birds and on young quail and grouse and function principally to conserve heat
10
Q
hollow bones
A
- hollow for lightness
- struts that make them about as strong as a solid bone
11
Q
flight muscles
A
- arranged to keep the center of gravity low in the body
- both major flight muscles are anchored to the sternum keel
- contraction of pectoralis muscle pulls the wing downward
- as pectoralis relaxes, the supracoracoideus muscle contracts and, acting as a pulley system, pulls the wing upward
12
Q
beaks
A
- strongly adapted to specialized food habits
- generalize (strong, pointed beaks of crows and ravens)
- highly specialized (flamingos, pelicans, woodpecker)
13
Q
cardinal beak
A
seed cracker
14
Q
flamingo beak
A
zooplankton strainer
15
Q
american avocet beak
A
worm burrow probe
16
Q
pelican beak
A
dip net
17
Q
parrot beak
A
nut cracker
18
Q
eagle beak
A
meat tearer
19
Q
anhinga beak
A
fish spear
20
Q
single reproductive tract of female bird
A
-egg yolk made in liver
- yolk accumulated in ovary one egg at a time
- egg passes down oviduct gathering albumin (egg white)
- calcareous shell made last at base of oviduct
- takes about 1 day to traverse system, so a clutch of eggs takes several days
21
Q
bird respiratory system
A
- trachea and lungs, complex system of air sacs
- air sacs double the efficiency of a mammalian lung
- air sacs do not respire, only distribute air, lung respire
- enables flight at high altitudes when mammals are prostrate
- air sacs serve as reservoirs of fresh air
22
Q
one-way movement of air through an avian lung
A
- tubelike parabronchi has air flowing through it continuously
- most inspired air bypasses lungs and flows directly into posterior air sacs (reservoirs for fresh air)
- on expiration, the oxygenated air passes through the lungs
- second respiratory cycle draws air from lungs to anterior air sacs and then to the outside
- takes two respiratory cycles for a single breath of air to pass through the respiratory system
- almost continuous stream of oxygenated air is passed through a system of richly vascularized parabronchi
23
Q
circulatory system of crocodiles, birds, mammals
A
- four chambered heart= large with strong ventricular walls
- complete separation of respiratory and systemic circulations
- fast heartbeat
24
Q
paleognathae (ratites)
A
- Ostrich (Africa)
- Cassowary(australia)
- Kiwi (New Zealand)
- characteristic “old jaw”
- use wings for displays
- mostly flightless
25
Neognathae (Carinates
- loons
- can dive after fish deeper than almost any other birds
- icon of the Adirondacks
- affected by quality of water in lakes (eat fish)
- "new jaw"
26
Emperor Penguin
- Antarctica
- flightless, but wings are great paddles
- males incubate an egg of their feet all through the winter
- thick layers of fat
27
Albatrosses and Petrels
- live their entire lives at sea except for breeding season often on islands
- good gliders
- hunt for squid/things on ocean surface
- gland in head that secretes salt (near nostrils)--> gets rid of excess salt from eating fish
28
Wilson's storm petrel
- nest in Antarctic area
- summers in North Atlantic
29
Cormorants
- Peru
- world first source of phosphorus fertilizers from guano
- used in Asia for fishing
30
Herons
- long legs for wading and spear bills for fishing
- nest in colonies, disperse to fish, bring back food to young
- stand still and wait for fish to come close
31
wood ducks
- males display and mate but do not raise young
- males are ornate
- males help females find nesting site (hole in a tree), abandons her after finding site, female incubates and raises young
32
vultures
- scavengers
- defenses agsint contamination
- bare heads--> stick heads in dead carcass, don't want feathers to get that on it
33
turkey vulture
- can smell carcasses as they fly over a forest
34
falcons, hawks, eagles
- decimated in 1960s by DDT (eggs were soft--> got crushed)
- recovered with help, now common
- DDT was banned
35
Peregrine falcons
- adapted well to cities
- nested on cliffs
- fly high above flocks of birds and drop, hit bird, stun it, grab it and eat it
36
Phesants
- Asian, but introduced for sport hunting
- males are ornate to attract females that are camouflage brown
- make nests on the ground
- females do all the incubation and raising of young
37
Piping plover
- shorebird
- nests on Atlantic beaches so are highly threatened by human activity
- nest on beaches above high tide line
38
red knot
- shorebird
- a sandpiper that winters in South America and migrates to the arctic tundra with one stop on the way= Delaware Bay for horseshoe crab eggs
39
Bar-tailed Godwits
- shorebird
- migrate from Alaska to winter in New Zealand
- takes them 11 days of non-stop flying at ~55 mph
- nest in Alaska, eat a lot when fall comes--> fly to New Zealand in one go
- very streamlined
40
Phalaropes
- sexes reverse roles: females lay eggs, but males incubate eggs at nest and care for young
- females have brighter plumage as they solicit males
41
Passenger Pigeons
- once most abundant bird in North America
- rendered extinct in 1914 by overhunting and habitat loss
42
Cuckoos
- famous as most species are brood parasites on other birds
- lay eggs in other nests
- hatch early, push out their original eggs
- host ends up feeding the cuckoo chicks
43
owls
one of few nocturnal birds
- can hunt by sound
- have good eyes as well
- sit on perch, hear soemthing rustling, track it, grab it with talons
44
snowy owl
- diurnal owl
- arctic
- occassionally occurs here in winter when prey are scarce in arctic
45
Hummingbirds
- New World family of birds
- specialize in nectar feeding
- the only birds that can truly hove in still air
- abundant in tropics because flowers are so abundant
- hover with small body and rapid wing beats
- males have ornate plummage
46
woodpeckers
- specialize in drilling into trees for large insect grubs
47
Pleated Woodpecker
largest of 6 species in BU Nature preserve
48
Bowerbirds
New Guinea/Australia
- birds whose males build gardens to attract females
- females incubate and care for young
49
Birds of paradise
- extraordinarily ornate males of New Guinea/Australia that also have complicated displays
50
Thrushes
- camouflage coloration but are the prime songsters of the bird world
51
wood warblers
- New World family
- 25 insectivorous species that live or migrate through here
- most overwinter in Central or South America
- ornate, diverse
52
Red-eyed Vireo
most abundant bird east of Mississippi
53
Wing stroke cycle
1. wings sweep downward and forward fully extended
(thrust is provided by primary feathers at the wing tips)
2. to begin upbeat, the wing is bent, bringing it upward and backward
3. the wing extends, ready for the next downbeat
54
wing angles
- low speed: angle of attack must increase to maintain lift, this increases the threat of stalling
- low speed stalling can be prevented with wing slots
- wing tip vortex, a turbulence that tends to develop at high speeds, reduces flight efficiency--> reduced in slender wings that sweep back and taper to a tip
55
elliptical wings
- large wing slots
56
high-speed wings
- slender tip, no wing slots
- sweep back
57
active soaring wings
- no wing slots
- long, narrow wings
58
passive soaring wings
- wing slots
- broad wing
59
Blackpoll Warbler
- when there's a Westerly wind, they launch out to Atlantic with angle toward south, eventually pick up trade winds and end up in South America for the winter
60
How do birds orient and find their way
- Gustav Kramer's experiment
- in migration season, a caged starling will restlessly hop in one direction guided by direction of the sun (north in spring)
- used a mirror to alter sun direction by 90 degrees--> bird alters direction of hopping by 90 degrees
61
Pigeon migration
- pigeons that migrate during completely overcast days can use the Earth's magnetic field
62
small bird migration
- small birds that migrate at night use the stars
63
bird reproduction
- many look monogamous, but DNA analysis shows mating outside pair happens
64
polygamous bird mating systems
- male calls from one place, then displays when female approaches and does no brood care
- ex: bird of paradise
65
"Lek" displays
- many males display in one place, and females come and choose
- usually one or a few males do most of the mating
- ex: Great Prairie Chicken in Great Plains US
66
altricial young
- young born naked and helpless and must be fed by parents in the nest
- most perching birds
- usually grow very rapidly
- hatching to fledging in <2 weeks
67
Precocial young
- young born downy and ready to leave nest and feed
- usually guided and protected by parents
- ex: ducks, geese, chickens, turkeys, shore birds
- incubate longer
