Ornithology Exam 1 - High-Specificity Practice Flashcards

Comprehensive vocabulary flashcards covering avian anatomy, history, evolution, physiology, and behavior as discussed in the lecture transcript.

Bird

A warm-blooded (endothermic) vertebrate in Class Aves that evolved from theropod dinosaurs, characterized by feathers, a beak, wings, and a highly efficient respiratory system.

Pectoralis major

The largest muscle in the body, originating on the keeled sternum and inserting on the humerus to produce the powerful downstroke in flight.

Supracoracoideus

The muscle lying beneath the pectoralis that raises the wing during the upstroke via a tendon passing through the triosseal canal.

Pneumatized bones

Hollow bones containing air spaces that reduce body mass without sacrificing strength.

Rectrices

Tail feathers used for steering, braking, and balance during flight.

Aristotle

First one to write about ornithology, classify them, and learn migration

Frederick II

Bird flight, hunting

Carl Linnaeus

binomial nomenclature and modern taxonomy.

John James Audubon

Painter, killed to pose them, taxidermy

Roger Tory Peterson

Creator of the modern field guide based on identification by field marks.

David Allen Sibley

Author of a leading current field guide known for detailed illustrations emphasizing identification.

Adaptation

An inherited trait that increases an organism's survival and reproductive success.

Flight

Wings, feathers, hollow bones

Walking

Strong legs, long toes

Perching

Tendon locking mechanism

Swimming

Webbed feet, waterproof feathers

Feeding

Specialized bills & tongues

Species

A group of organisms capable of interbreeding naturally to produce fertile offspring.

Classification

D,K,P,S,C,O,F,G,S

Who did birds evolve from? Evidence?

Theropod dinosaurs

Feathers, hollow bones, wishbone, 3 fingers, fossils, DNA

Archaeopteryx lithographica

Transitional fossil linking reptiles (teeth, long bony tail, claws) and birds (feathers, wings, furcula).

Cursorial Hypothesis

The "ground-up” theory for flight evolution suggesting running dinosaurs developed powered flight. Wing-assisted running.

Arboreal Hypothesis

The "tree-down" theory for flight evolution suggesting tree-climbing ancestors began by gliding down.

Wing-Assisted Incline Running (WAIR)

A behavior in running theropods used as evidence for the cursorial origin of flight.

What factors have contributed to the rapid speciation of birds?

• Flight

• Geographic isolation

• Island colonization

• Natural selection

• Sexual selection

• Climate fluctuations

Lift/Airfoil

The force generated by a difference in air pressure between the upper (convex) and lower (flatter) surfaces of an airfoil.

Thrust/Primaries

Feathers attached to the hand (manus) used primarily to produce thrust.

Lift/Secondaries

Feathers attached to the ulna used primarily to produce lift.

Alula

Small feathers on the first digit that maintain airflow over the wing to prevent stalling during landing.

Wing types

Long, narrow

Short, rounded

Slim, unslotted

Slotted

Upwash

The rising air created by trailing vortices of a leading bird's wingtips, which following birds use to save energy in a V formation. Less drag

Anisodactyl

A foot arrangement with three toes forward and one back, typical for perching birds.

Zygodactyl

A foot arrangement with two toes forward and two back, common in woodpeckers for climbing.

Pamprodactyl

Toes forward

Syndactyl

2 toes fused

Palmate

Webbed feet found in ducks to aid in swimming.

Feather growth

Develop from follicles.

Growing feather supplied by blood.

When mature

• Blood supply disappears.

• Feather becomes dead keratin.

Melanin

A pigment that produces black and brown colors. Patterns

Carotenoids

Red, orange, and yellow pigments obtained from a bird's diet.

Psittacofulvins

Red/yellow in parrots only

Porphyrins

Megenta, green

Structural colors

Colors like blues and iridescence produced by refraction of light

Calamus

The hollow, pigmentless base of the feather shaft that attaches to the follicle.

Rachis

The solid upper portion of the feather shaft to which the vanes are attached.

Hooklets/Barbicel

Microscopic structures that zip barbules together to maintain a smooth, air-resistant vane.

Filoplumes

Sensory feathers that monitor the position and movement of other feathers.

Bristles

Like whiskers. Protect eyes and nose, help insect capture

Powder down

Waterproofing powder

Flight benefits

• Escape predators

• Find food

• Migrate

• Reach nesting sites

Flightless bird benefits

• Lower energy cost

• Larger body size

• Stronger legs

Basal Metabolic Rate (BMR)

The minimum energy required by a bird at complete rest.

Thermoneutral Zone (TNZ)

The temperature range where a bird's metabolic rate is at its lowest.

Lower Critical Temperature (LCT)

The temperature below which a bird must increase its metabolism, shiver, and increase oxygen consumption to maintain body heat.

Upper Critical Temperature (UCT)

The temperature above which a bird must use evaporative cooling methods like panting or gular flutter.

Torpor

A state where a bird lowers its body temperature and metabolism to conserve energy.

Gular flutter

A cooling behavior where birds rapidly vibrate their throat membranes.

Respiratory system

Site of gas exchange

No expansion like mammals

One-way airflow

Fresh air passes through during both inhalation and exhalation

Circulatory system

Four chambers

Complete separation of oxygenated and deoxygenated blood

Large heart

Rapid circulation

High blood pressure

Nucleated red blood cells

Digestive system

Beak

Esophagus

Crop

Proventriculus

Gizzard

SI

LI

Cloaca

• Coprodeum

• Urodeum

• Proctodeum

Bills & tongues

Associate form with function.

Hooked → tearing meat

Conical → crushing seeds

Chisel → drilling wood

Long probe → mud probing

Flat lamellate → filter feeding

Tongues

Woodpecker

• Barbed

Hummingbird

• Bifurcated, tubular

Duck

• Lamellae assist feeding

Excretory system

Uric acid

No bladder

2 nephrons:

• Mammalian - Loop of Henle, concentrates urine

• Reptilian - No loop, uric acid

Nervous system

Large cerebellum

• Flight coordination

Large optic lobes

• Vision

Tetrachromatic vision

Two foveae in many species

Excellent balance

Air sacs

Nine thin-walled sacs that act as bellows to move air through the respiratory system but do not perform gas exchange.

Parabronchi

The site of gas exchange within the rigid avian lungs.

Crop

A specialized part of the esophagus used for the storage of food.

Proventriculus

The glandular stomach where chemical digestion begins.

Gizzard

The muscular stomach used for mechanical grinding of food.

Coprodeum

The first chamber of the cloaca which receives feces from the large intestine.

Urodeum

The middle chamber of the cloaca which receives products from the urinary and reproductive ducts.

Proctodaeum

Projectile poops

Bills

Hooked → tearing meat

Conical → crushing seeds

Chisel → drilling wood

Long probe → mud probing

Flat lamellate → filter feeding

Depressed

Compressed

Recurved

Decurved

Straight

Bent

Chisel

Tongues

Barbed - probing, spearing

Tubular - nectar

Hooks - fish

Food straining - filtering

Calls

• Innate

• Short

• Alarm

• Contact

• Begging

• Flock cohesioN

Songs

• Learned

• Longer

• Territory defense

• Mate attraction

Syrinx

The avian vocal organ located where the trachea divides into the bronchi, capable of producing two sounds simultaneously.

• Located where the trachea divides into the bronchi

• Membranes vibrate as air passes through

• Birds can control each side independently, allowing some species to produce two different sounds simultaneously

Photoperiod

Day length; the most reliable external cue used by birds to time molting, migration, and mating.

Nomadic wandering

Irregular movements of birds in response to changing food availability or weather, as opposed to predictable seasonal migration.

Magnetoreception

The ability to navigate using the Earth's magnetic field.

Molting, migration, mating

Require high energy.

Internal cues

• Hormones

• Circannual rhythms

External cues

• Photoperiod (day length; the most reliable cue)

• Temperature

• Food availability

Timing ensures breeding, migration, and molt occur when conditions maximize survival and reproductive success.

Migration patterns

North–South

East–West

Altitudinal

Loop migration

Migration

• Predictable seasonal round trip

Nomadic wandering

• Irregular movements in response to changing food or weather

Costs/Benefits of migration

Benefits

• More food

• Better breeding habitat

• Longer daylight

• Less competition

Costs

• High energy expenditure

• Predation

• Severe weather

• Collisions

• Starvation

Navigation

Birds use multiple orientation cues:

• Sun compass (uses the sun’s position with an internal biological clock)

• Star compass (especially important for nocturnal migrants)

• Earth’s magnetic field (magnetoreception)

• Polarized light (helps determine the sun’s position when obscured)

• Landmarks (coastlines, rivers, mountains)

• Olfaction (smell, especially in pigeons, petrels, and some seabirds)