Term
| Which characteristics/traits unify birds, and which are unique to birds? |
|
Definition
| Birds have: beaks, feathers, hollow bones, air sacs, digestive system specialization, lay eggs, excrete uric acid, have a furcula, songs (syrinx), high body temp, elaborate parental behavior, nourishment instead of lactation |
|
|
Term
| Palaeognathae (the ratites and tinamous) |
|
Definition
Tinamiformes - Tinamous
Rheiformes - Rheas
Struthioniformes - Ostrich
Casuariiformes - Cassowaries
Dinornithiformes - Kiwis |
|
|
Term
| Neognathae (all other modern birds) |
|
Definition
Podicipediformes - Grebes
Sphenisciformes - Penguins
Procellariiformes - Tube-nosed Seabirds
Pelecaniformes - Pelicans and relatives
Anseriformes - Waterfowl
Phoenicopteriformes - Flamingos
Ciconiiformes - Herons, Storks, New World Vultures and relatives
Falconiformes - Diurnal Birds of Prey (no species list yet)
Galliformes - Fowlike Birds
Gruiformes - Cranes, Rails and relatives
Charadriiformes - Shorebirds, Gulls and relative
Gaviiformes - Loons
Columbiformes - Pigeons and Doves
Psittaciformes - Parrots (no species list yet)
Coliiformes - Mousebirds
Musophagiformes - Turacos
Cuculiformes - Cuckoos
Strigiformes - Owls
Caprimulgiformes - Nightjars and relatives
Apodiformes - Swifts and Hummingbirds
Trogoniformes - Trogons
Coraciiformes - Rollers, Kingfishers and relatives
Piciformes - Woodpeckers, Toucans and relatives (no species list yet)
Passeriformes - Perching Birds (no species list yet) |
|
|
Term
| What are the similarities and differences between birds and reptiles. Archaeopteryx – what is it, when did it exist, why was it an important finding, what characteristics (reptilian and avian) did it possess. |
|
Definition
Similarities: Differences:
Yoked eggs Birds are endothermic
Scales Birds have a high degree of parental care
Lower mandible has 5 bones Birds can lay one egg per day
Ankle joint
Only stapes
Nucleated red blood cells
Females are heterogametic
Single occipital condyle |
|
|
Term
|
Definition
Found in Germany in 1861
About 150 mya
Had reptilian and avian characteristics
First only a feather was found
Today we know of 7 specimens
Similar to avians, it had: feathers, furcula, the angle of the scapula, a reversed hallux
Different to avians, it didn’t have: fused pelvic bone, no pygostyle, and no uncinate processes
Significance:
Provided support for Darwin’s theory
Missing link
Suggested timing for evolutionary birds |
|
|
Term
| Explain the Thecodont versus the Theropod theory for the origin of birds. What are the problems associated with these theories. Describe how archaeological findings such as Protoavis, Caudipteryx, Unenlagia, Oviraptora support of each theory and explain which traits provide supportive evidence. |
|
Definition
Thecodont reptile theory of avian origins:
G Heilman, 1926
Small thecodont reptiles
Early Triassic @230 mya
Clavicles (=furcula=wishbone)
Sharp teeth set in sockets
Highly arboreal; bipedal
Problem: 90 million year gap |
|
|
Term
|
Definition
No feathers but furcula
Thecodont skull
toothed jaw
arboreal
bipedal |
|
|
Term
| Theropod dinosaur theory of avian origins: |
|
Definition
Jurassic @ 150-110 mya
Small; Bipedal Sharp teeth (e.g. Velociraptor)
1-timing wrong ancestor
2-theropods have conical teeth with serrations
3- bird digits II, IV, IV (Dino digits I, II, III |
|
|
Term
|
Definition
Theropod dinosaurs not birds
Symmetrical feathers but no flight
About 135 mya |
|
|
Term
|
Definition
90 mya
Many theropod features (pelvis)
Bird features:
Shoulder joint, could raise forelimb, could fold wing, no feathers |
|
|
Term
| What factors significantly affected avian diversification in the Eocene and the Pleistocene? |
|
Definition
Eocene: (37-53 mya)
Radiation of flowering plants and grasses
Radiation of birds and mammals
Pleistocene: (2 mya and less)
Ice ages
Seasonal climate
Many birds species go extinct
21,000 species to less than 10,000 |
|
|
Term
| Flight either evolved from cursorial or arboreal ancestors; explain these two theories and their association with the Thecodont or Theropod theory for the origin of birds. |
|
Definition
Cursorial:
Ground up
Evolved from a running ancestor
Associated with theropod dinosaur theory
Origin of feathers
Insulation at night; reflection from hot sun
Insect traps, swat insects, tail to stabilize
Better control of body during leaps
Bi-pedalism frees arms
Arboreal:
Trees down
Associated with thecodont reptile theory
Insulation in trees habitat
Surface area to glide
Glide from tree to tree to chase prey and escape from predators |
|
|
Term
| Early birds can be classified into subclass: Ornithurae and subclass: Sauriurae. Describe two species for each subclass, provide approximate dates of existence, which subclass is believed to include ancestors of present-day birds? Explain the existence of species such as Diatryma. |
|
Definition
Sauriurae:
Archaeoptyryx
Confuciusornis
Ornithurae:
Ichthyornis
Toothed
Good flier
Associated with water
Kansas, Montana, Texas
Hesperornis
Toothed
Aquatic
Vestigial wings
N. Dakota, Kansas, Nebraska
Ancestors to modern birds
Went extinct during the Cretaceous extinction
65 mya
Asteroid collision
Many bird groups extinct
Those remaining are ancestors of paleognaths and neognaths |
|
|
Term
| Compare and contrast the theory that the origin (radiation) of modern birds occurred after the great cretaceous extinction (Teritary big bang) with the theory that the origin of modern birds occurred during the cretaceous period (Gondwanagenesis). What supportive evidence is there for ‘Teritary big bang’ and for ‘Gondwanagenesis’? |
|
Definition
Big Bang:
Most modern bird families were present 35 million years ago
Dinosaurs became extinct 65 million years ago
Diatrymas were some of the first birds
Large, flightless predators
Thought to have taken over the niche left behind by dinosaurs
Cretaceous Period Extinction:
Most modern bird orders originated in the middle Cretaceous period and gradually evolved into the modern forms
Likely from primitive shore birds |
|
|
Term
| Describe oscine and suboscine radiation as describe by Baker et al. 2004 (phylogeny on your handout). Approximately when did suboscines diverge from Oscines? Are New World Suboscines or Old World Suboscines more diverse? Which are more diverse the clade Corvoidea or the clade Passeridea? |
|
Definition
Subocines diverged from oscines around 70 mya in the end of the Cretaceous period
New world suboscines are more diverse
Passeridea is more diverse |
|
|
Term
| Describe several morphological traits that are conservative characteristics which can be used in classification. Explain the problem of divergence versus convergence of traits. |
|
Definition
Toe arrangement
Bony palate
Leg musculature
Internal/External nostrils
Arrangement of scutes and scales
Convergence: Birds are unrelated with similar adaptations
Eastern Meadowlark and yellow throated longclaw
Divergence: Birds can be closely related and have different styles of flight, color, etc… |
|
|
Term
| What are the benefits and drawbacks of the various techniques (morphological, behavioral, biochemical) that are used to study avian systematics. Describe the technique used to reclassify the New World Vultures. |
|
Definition
DNA studies have problems because:
Convergence is present
Biochemical classification of birds
Many uncertainties with all of these techniques
Convergent evolution is a problem
DNA studies have proven valuable
The technique used was DNA-DNA hybridization
Unzipped strands of DNA are placed with other unzipped samples….whichever ones fit together the best have the closest relation and are more stable |
|
|
Term
| Biological Species Concept: |
|
Definition
Groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups
Lumping of distinct populations that partially interbreed
Major concept:
Reproductive Compatibility
Problems:
Its hard to know whether or not similar species would interbreed because they usually live in different parts of the world |
|
|
Term
| Phylogenetic Species Concept: |
|
Definition
Populations of discrete, recognizably different forms with separate evolutionary histories
This concept is more concerned with separate evolutionary histories than interbreeding individuals
If two forms became different because they diverged genetically at some point in their evolutionary history, the PSC considers them separate species
Problems:
Under this concept, the number of bird species in the world would be double the number recognized with the BSC |
|
|
Term
|
Definition
A population of a species that has some unique characters and some that are shared with other populations, and which can interbreed with other populations when they meet
Subspecies are separated geographically, not reproductively
Unique character states maintained by reproductive isolation
Three Latin names |
|
|
Term
|
Definition
| If a species ranges widely over geographical areas that encompass shifts in environmental conditions, such as from warm to cold or humid to arid climates, it is likely too show a gradual changed (CLINE) in certain characters from one population to the next |
|
|
Term
| Why does geographic isolation likely lead to speciation? How can behavior of species that are geographically not isolated lead to speciation? What forces are acting that favor differentiation versus blending of population characteristics? Explain adaptive radiation, and provide a few examples. |
|
Definition
Geographic Isolation:
Dispersal events
Female dispersal male phylopatry
Random events (storms)
Habitat fragmentation
Separated by glaciation events
Separated by formation of water bodies
Adaptive Radiation:
The formation from a common ancestor of a variety of different species adapted to different niches and behaviors, usually showing different morphologies
E.G. When a group of islands is colonized, natural selection may proceed differently on the different islands, eventually producing an array of new species
E.G. Black headed and rose-breasted gross beaks |
|
|
Term
|
Definition
The range where two interbreeding species meet
1) Low vigor of hybrids or their offspring
E.G. Eastern/Western Meadowlark…F1 is sterile…eggs not viable
2) Low frequency of hybridization
E.G. Rose-breasted/Black headed grosbeaks…hybrids lay smaller clutches |
|
|
Term
|
Definition
Where hybridization persists
Does not lead to population fusion or assortive mating and speciation
Explained by two theories
1) Dynamic equilibrium
Inferior hybrids are continuously produced
2) Bounded superiority
Hybrids are superior only in the hybrid zone
E.G. Bullocks Oriole and Baltimore Oriole |
|
|
Term
|
Definition
Genetic swamping
One species takes over
E.G. Golden-winged warbler over Blue-winged warbler |
|
|
Term
| What are the general and modified functions of feathers. Are feathers located over the entire body of a bird? Why or why not? |
|
Definition
1) Protect and insulate the skin and body
2) Provide streamlined surface area required for efficient flight
3) Providing pattern and color
No they are not over the entire body because certain areas like the feet, eyes, and bills do not need them |
|
|
Term
Feathers maintain their color by two mechanisms
1) Chemical |
|
Definition
Pigments
Absorption vs. reflection
These colors are produced chemically
Carotenoids-Red/yellow
Birds cannot make them so they must get them from their diet
Porphyrins-reds/browns/greens
Melanin-blacks/grays/browns
Most common
Associated with keratin |
|
|
Term
|
Definition
Structural elements modify light
Blue-scattering of short wave lengths
Grinding up the feather would produce a dark black because the color in the feather is in the structure not pigment
In tiny air pockets and granules
Light hits pockets and reflects blue
UV wavelength is shorter birds see it we cant
Iridescence-Interference of reflected light from outer and inner surface of granules
Angle of view is important
White color is structural only because it reflects all colors
Black absorbs all colors |
|
|
Term
| Most common molting pattern |
|
Definition
Natal down---Prejuvenal molt
Juvenal plumage—prebasic molt
1st basic plumage—pre-alternate molt
1st alt plumage—pre-basic molt
Basic plumage—prealternate molt
Alternate plumage
Many birds have 2 molts per year…one complete one partial |
|
|
Term
|
Definition
Have overlapping pre-basic and pre-alternate molts
After breeding à pre-basic molt à Eclipse plumage
Before migration à pre-alternate molt à alternate plumage |
|
|
Term
| skeletal adaptions for flight |
|
Definition
Bill instead of teeth
Hollow bones with diagonal struts
Pneumatization-Airsacks in the long bones of the wing
Shrunken gonads when not breeding
Fusions:
Rigid skeleton
Hand, finger, and wrist bones
Only two carpels and a carpometacarpus
Pelvic girdle
Free tail bones and pygostyle
Reinforcement
Large Breastbone (sternum) with keel
Uncinate processes between ribs
Wing joints are modified – Folding at rest and locking in flight
Furcula functions as a sring and air pump
Distribution of weight
All around center of gravity
No bony tail
No toothed jaw
Mainly tendons extremities
Flight muscles are ventral |
|
|
Term
| muscular adaptions for flight |
|
Definition
About 50 flight muscles
Pectoralis
Downstroke
Supercoracoideus (through the foramen triosseum)
Upstroke
Mass of these two muscles = ¼ body mass
Very developed in divers
Reduced in flightless birds
Red-aerobic, sustained flight
White-anaerobic, bursts |
|
|
Term
|
Definition
Because the wings shape is convex (rounded) on the top and concave (curved inward) below. This shape creates lift as the airfoil moves through the air
Dynamic pressure and static pressure offset each other…if one increases the other must decrease
Bernoulli’s law states how because the dynamic pressure above the wing increases, the static pressure must decrease
Higher static pressure below the airfoil creates an upward force known as lift
The bird gets lift because the static pressure above the wing Is lower than the static pressure below the wing |
|
|
Term
|
Definition
| A bird can vary the amount of lift that its wings generate by changing the angle between the wing and the oncoming air stream |
|
|
Term
|
Definition
The force that slows down a gliding bird eventually to the point which it can no longer maintain necessary lift for flight
Basically friction between air and a moving body
To reduce drag, decrease the angle of attack |
|
|
Term
|
Definition
The ratio of length to the width of a wing
Long, narrow wings have a high ratio
Short broad wings have a low ratio |
|
|
Term
|
Definition
A group of two to six feathers projecting from the birds first finger or thumb at the bend of the wing.
Reduces turbulence by allowing fine control of airflow over the wing |
|
|
Term
| Compare flapping, and soaring flight, and flying in formation. |
|
Definition
Soaring
Flying without flapping the wings while gaining altitude or remaining horizontal
Flying in formation
Vortexes at wing tips provide lift
Flying in formation probably confers an energetic advantage
Flapping
For typical flapping flight, the most efficient wings are large, long, and relatively narrow |
|
|
Term
|
Definition
(Chicken, passerine)
Low aspect ratio
Good for flapping bursts
High maneuverability |
|
|
Term
|
Definition
(Eagle, Buteo’s)
Slotted
High lift
Static soaring
Moderate aspect ratio
High Speed (Falcons, Swifts, Ducks) |
|
|
Term
|
Definition
(Falcons, Swifts, Ducks)
High aspect ratio
Strong bones = more profile drag
Lots of flapping |
|
|
Term
|
Definition
(Albatross, Gannets)
Elongated ulna
Induced drag
Dynamic and static soaring |
|
|
Term
| Using your textbook discuss whether flightlessness is an ancestral or derived trait. Describe some species that are flightless and explain why these species lack the capability of flight. |
|
Definition
| Flightlessness is a derived trait when the species finds no strong advantage to flying for many generations |
|
|
Term
| What is migration, dispersal, and irruptive behavior. Why do some species migrate and others are year-round residents of a given area? How does a species lifestyle affect the time (day or night) of migration. |
|
Definition
Migration
The regular movement of all or art of a population to and from an area…usually refers to seasonal journeys to and from breeding grounds or feeding areas
Dispersal
The movement of individuals away from the area where they were born, or away from areas containing concentrations of individuals
Irruptive Behavior
Migratory movements that are irregular in time and space depending on factors other than a change of seasons, such as food availability
Flexible migrators
Waterfowl
Nocturnal
Majority of species
Small land birds
Mid-day
Soaring, gliding birds
Raptors
Diurnal
Finches, buntings, crows, swallows, doves |
|
|
Term
|
Definition
In the spring, northbound migrants move in great numbers with the southerly winds that accompany a warm front
The warm fronts usually occur before the passage of a low pressure region and after a high pressure system
Spring migration stops when a cold fronts north and northwest winds pass by |
|
|
Term
|
Definition
In fall, southbound migrants take flight after the passage of a cold front, when skies clear and northerly winds provide a favorable tailwind
Cold fronts usually occur after low pressure system and before a high
Fall migration may continue until the winds change to come from the south, as when a warm front arrives |
|
|
Term
| Is migration energetically expensive? How do birds ‘fuel’ migration? When does migration usually take place? Does migration coincide with molting, reproduction? Why or why not? |
|
Definition
Migration uses extreme amounts of energy
Fat reserves (hyperphagia)
Energy reserves, fat, carbs, proteins
The amount of fat varies
Long distance:
30-50% of body mass
Short distance
10-25% of body mass
Migration usually takes place when the weather becomes cold and food becomes scarce…at this time birds head for the equator (winter) |
|
|
Term
| Do birds always travel by the same route? What are flyways? Do all birds use flyways? Do all birds migrate to their wintering sites in one multi-day-and-night trip? What are stop-over sites? |
|
Definition
Flyway-the term used for flight paths in bird migration
Stop-over sites are particularly common in larger birds |
|
|
Term
| How do ‘biological clocks’ contribute to migration and navigation? |
|
Definition
| Regulate circannual rhythms that are cycles of behavior that occur yearly…the rhythms persist even when the animals are kept under constant environmental conditions |
|
|
Term
|
Definition
These gridmaps have two intersecting environmental gradients-North and South
Birds also have mosaic maps
These consists of:
Landmarks
Magnetic terrain
Mostly used in the vicinity of home |
|
|
Term
|
Definition
Maps gradients
Magnetic
Olfactory
Infrasound
Birds also use a solar compass
A mechanism by which birds and some other animals use the position of the sun in the sky to indicate compass direction. To do this, they must be able to compensate for the changing position of the sun during the day
Birds use star compasses
The mechanism by which nocturnally migrating birds are able to use the star patterns surrounding the North Star to determine which way is north. Learned by a young bird in the nest.
Magnetic Compass
Develops spontaneously in young birds |
|
|
Term
| What are the cues (gradients) that can provide a compass direction? Describe experiments that show that birds use the sun, the sun’s azimuth, the stars, the earth’s magnetic field, olfactory and auditory cues. |
|
Definition
Solar Compass
A study was done on starlings in orientation cages
Mirrors were used to shift the apparent position of the sun
Found that the birds shifted the direction of their migratory restlessness to match the compass directions indicated by the altered position of the sun
This demonstrated that in choosing directions the birds compensated for the changing position of the sun as the earth rotated on its axis
Star Compass
Birds were placed in a planetarium where they used the stars as a compass
Extensive studies on the indigo bunting proved that young buntings observe the rotation of the night sky that results from the earths rotation around its axis
They learn the center of this axis of celestial rotation so they can locate north
Magnetic field
Robins were covered in their cages and hopped in the right directions
Magnetic coils were placed on the cages and the birds changed their hopping according to the change in direction
Olfactory
Birds used gradient odor map of the vicinity of their home loft by associating airborne odors with directions from which winds carry them past the loft
Olfactory nerves were cut
Birds were transferred in sealed bottles
Not a lot is known about this |
|
|
