Chapter 21 - Avian Diversity and Form

pterylae

the specific, localized areas on a bird's skin where contour feathers grow

apteria

unfeathered skin

Calamus

base of the feather

Rachis

extends from calamus to tip of feather

barbs

branches off of rachis

barbules

branch off of barbs

vane

flexible side of the feather

plumaceous

downy feathers that are used for insulation

pennaceous

linked, vaned feathers wing and contour feathers

down

entirely plumulaceous feathers, rachis may be entirely missing; insulatory

natal down

simpler than adult, on birds at/after hatching, precede contour feather development

uropygial down

special down beside uropygial gland that help with oil transfer

powder down

disintegrate into powder of keratin; help waterproof

Bristles

stiff rachis; barbs on proximal portion or none at all

filoplumes

fine, hairlike feathers with few barbs/barbules

primary feathers

these feathers are located on hand bones and are used for propulsion

secondary feathers

these feathers are located on ulna bones and are used to provide lift

tertiary feathers

these feathers are located on humerus bones and are used for protective cover when wings are folded

synsacrum

fusion of 10-23 vertebrae

pygostyle

shortened tail, and the fusion of remaing vertebrae forms this structure

furculum

wishbone (one of the bracing bones)

uncinate processes

located on the ribs and is one of the bracing bones

around 2.25x

How many times does the power for takeoff increases by for each doubling of body mass?

horizontal thrust and vertical lift

What two principles are required for flight?

thrust

mainly generated by the primary feathers, which on the downstroke twist and acting like a propeller push the air backwards.

lift

mainly generated by the secondary feathers, which form an airfoil (increased pressure also generates this)

airfoil

the combination of a slightly convex upper surface and a concave under surface

alula

feathers attached to “thumb”

high aspect ratio

Dynamic soaring, gliding in high-wind environments; long for lift, narrow for less drag, no slotting at wing tip.

high speed

speed and control for aerial foraging, long migration; triangular shape for less drag, high aspect ratio but moderate length, no slotting at wing tip

Elliptical

rapid take-off, high maneuverability; short & broad (low aspect ratio) with slotted tips

high lift

static soaring; large surface area, slotted tips

Pectoralis major

this muscle adducts and depresses wing

Suprocoracoideus major

this muscle abducts and elevates the wing

triosseal canal

formed by the junction of the coracoid, scapula and furcula

supracoracoideus tendon

passes through the triosseal canal up from the supracoracoideus and inserts on the dorsal face of the humerus

myoglobin

more of this binding protein forms a darker color, and they have a high capacity for aerobic metabolism

tibiotarsus

fusion of tarsal bones (calcaneum & astragalus) to bottom of tibia (location of the drumstic)

tarsometatarsus

fusion of tarsals and metatarsals; long bone leading from “ankle” to the toes (helps allow perching!)

being able to prech

What is an early avian adaptation?

anisodacyl foot

have four moderately long toes, three facing forward and one back

zygodactyl foot

two toes forward, two toes back; allows for climbing on vertical surfaces (tree trunk)

didactyl foot

features only two digits (toes) per limb

uropygial gland

large preen gland for oil production

a high and efficient metabolism

What physiological requirements are needed for flight?

crop

excess food is stored here in birds

crop milk

fat laden cells in fluid; high in lipids/proteins but no sugar

Hoatzin

What South American bird is the nly bird that uses its crop as a fermentation chamber?

proventriculus

anterior glandular stomach

gizzard

posterior muscular stomach

True

True or False: Gut morphology changes seasonally in birds

True

True or False: The quantities of digestive enzymes produced are tailored to match the

composition of the diet

anterior and posterior air sacs

act as bellows to create a highly efficient, one-way flow of air through stiff, non-expanding lungs

True

True or False: birds use the two breath cycle

Monocular vision

used when on sides for a greater field of view to see predators

binocular vision

used when in front for a better depth perception to judge distance to prey

tetrachromatic

4 photosensitive pigments in retinal cells

True

True or False: in most birds, olfaction is unimportant and the olfactory bulbs are small

True

True or False: Birds have a proportionally much larger tympanic membranes that enhances sensitivity to sound

Vocalizations

push air through syrinx

syrinx

unique vocal organ of birds, located deep in the chest where the trachea (windpipe) forks into the lungs

sonation

generate sound with bill or feathers; nonvocal

ovary

eggs are produced in this organ

oviduct

Ovulated eggs enter the upper part of this organ; where fertilization occurs

shell gland

where the egg’s shell is added

Oviparous

birds use this type of reproduction to produce offspring

air pocket

Evaporation of water creates ___ ______ within the egg?

egg tooth

hypertrophied muscle in neck for extra strength

ZZ

homzygous male genotype

ZW

heterozygous female genotype

synchronized hatching

waiting to incubate until clutch is complete

prolactin

suppresses ovulation & egg laying and induces brooding behaviors and formation of brood patches

brood patches

featherless, fluid-filled area on the abdomen or breast of birds that is filled with surface blood vessels to help with incubation

monogamy

one male and one female form a pair bond to raise a family

genetic monogamy

male and female share responsibility of clutch and demonstrate fidelity.

social monogamy

male and female share responsibility of the clutch, but do not demonstrate fidelity

polygamy

two or more partners of the opposite sex at the same time, and parents will not share equally in chick-rearing duties

polygyny

male with many females; male protects and fertilizes all the females, but will play no part in brood rearing

polyandry

female mates with several males, she leaves each male to brood and rear the chicks alone, while she seeks out more breeding opportunities

precocial

eyes open, covered with feathers or down, leave nest after one or two days

semipercocial

eyes open, covered with down, able to walk but remain at nest and are fed by parents: gulls, tems

semialtricial

covered with down, unable to leave nest, fed by parents

altricial

eyes closed, little or no down, unable to leave nest, fed by parents: passerines

True

True or False: high-frequency songs are less attractive to female birds