Chapter 4: Feathers Flashcards
powder down
*quil continously growing and disintegrating, creating powdery substance
*barbs disintegrate, providing a fine powder thought to aid in preening and waterproofing the other feathers
*only feathers that grow continuously, never molted
*most prominent on breast/belly of herons and bitterns (family Ardeidae)
- capital
- humeral
- alar
- femoral
- crural
- spinal
- caudal
- ventral
- lateral branches from rachis
- smaller projections from barbs
- hooks that interlock to hold #1 in place
- barbs
- barbules
- baricels
shrike-thrushes (New Guinea forests)
hooded pitohui (Pitohui dichrous)
*secrete poisons from their preen gland (similar to the alkaloids produced by poison arrow frogs)
*produces a particularly large amount of these poisons
*quil continously growing and disintegrating, creating powdery substance
*barbs disintegrate, providing a fine powder thought to aid in preening and waterproofing the other feathers
*only feathers that grow continuously, never molted
*most prominent on breast/belly of herons and bitterns (family Ardeidae)
powder down
*caused by the physical alteration of incident light
*result from scattering of short wavelengths of incident light (blues) by small melanin particles in the feather barbs
*structural blues converted to greens and violets when combined with carotenoid pigments
Structural colors
body feathers (contour feathers)
*long central shaft w/ broad flat vane on either side
*vane base fluffy for insulation
plummage replaced following breeding (succeeds prebasic molt)
breeding plummage with brightly-colored feathers (succeeds prealternate molt)
basic (main) plummage
alternate plummage
*simplified feathers with sensory function; consist of a stiff rachis with a few basal barbs
*found mostly on head; also found on the knees of bristle-thighed curlews and on the toes of some owls
Bristles
uropygial (preen) gland
preening
*located on rump; secretes waxy/oily substance; some protect against bacteria, fungi, and ectoparasites (lice)
*grooming with beak + feet
basic (main) plummage
alternate plummage
plummage replaced following breeding (succeeds prebasic molt)
breeding plummage with brightly-colored feathers (succeeds prealternate molt)
*hairlike feathers that monitor movement and position of adjacent vaned feathers; might also have an ornamental function for displays (e.g. sage grouse)
*those associated with: flight feathers aid in aerodynamic adjustments; body contour feathers might help to monitor airspeed
*distributed inconspicuously throughout the plumage, but most numerous near moveable feathers
*fine rachis that terminates with a tuft of 1 to 6 short barbs with barbules
Filoplumes (absent in penguins, ostriches, and other flightless ratites)
natal down
second partial molt
replaces first molt with relatively normal assortment of feather types
mostly coat feathers; for adjusting coloration
coverts
*smaller feathers overlapping the bases of the remiges; covers gaps between remiges
*inner remiges attached to are bone (ulna)
*range from 6-40
secondaries
*secrete poisons from their preen gland (similar to the alkaloids produced by poison arrow frogs)
*produces a particularly large amount of these poisons
shrike-thrushes (New Guinea forests)
hooded pitohui (Pitohui dichrous)
Structural colors
*caused by the physical alteration of incident light
*result from scattering of short wavelengths of incident light (blues) by small melanin particles in the feather barbs
*structural blues converted to greens and violets when combined with carotenoid pigments
Bristles
*simplified feathers with sensory function; consist of a stiff rachis with a few basal barbs
*found mostly on head; also found on the knees of bristle-thighed curlews and on the toes of some owls
*acts to hide the birds outline
*dark dorsal surface absorbs light while the light underside reflects light, minimizing a shape-defining shadow
Counter shading (light ventral surface, dark dorsal surface)
(definitive down)
*soft and fluffy
*distribution can be continuous or restricted
*generally lack rachis (except waterfowl)
*Flexible barbs and barbules extend directly from the calamus (don’t interlock)
*They provide insulation by trapping air next to the skin
down feathers (in adults?)
down feathers (in adults?)
(definitive down)
*soft and fluffy
*distribution can be continuous or restricted
*generally lack rachis (except waterfowl)
*Flexible barbs and barbules extend directly from the calamus (don’t interlock)
*They provide insulation by trapping air next to the skin
- grays, blacks, browns, and buff colors; found in all birds
- yellows, oranges, reds, some blues and greens
- bright brown and green + unique magenta; unstable so do not last as they can be destroyed by sunlight; most often found in new feathers; structure related to hemoglobin
- melanins
- carotenoids
- porphyrins