Ornithology Lectures

Eukarya

To what domain do the birds belong?

Aves

To what class do the birds belong?

Feathers, bill, fused bones of pelvis, feet hands, and head, Bones are hollow or spongy making them very light, Endothermic with efficient cardiovascular and respiratory systems

Five distinguishing characteristics of birds

Anseriformes

To what order do ducks and geese belong?

Strigiformes

To what order do the owls belong?

Passeriformes

To what order do the perching birds and songbirds belong?

Insulation, aerodynamics, color for communication and camouflage, and protection

List four functions of feathers

Beta-keratin

From what material are feathers made?

Melanin

What pigment is responsible for producing the browns, gray, and blacks in feathers?

Rachis

The portion of a feather that supports the vanes is called what?

Filoplumes

What type of feather is used to monitor the movement of vaned feathers and to monitor air speed?

Pectoralis

What muscle is responsible for generating the downstroke during flight?

Supracoracoideus

What muscle is responsible for generating the upstroke during flight?

Lift

What is the name of the upward force that must overcome gravity if flight is to occur?

Drag

turbulence and air friction create what force that must be overcome if flight is to occur?

the amount of lift can be increased by increasing the angle of wing. If the angle increases too much, it increases the drag due to turbulence and can cause stalling, which can be useful during landing.

What happens as the angle of the wing is increased?

Large wings relative to body size are important for gliding and for efficient, maneuverable flight.

Large wings relative to body size are important for what types of flight?

Ectothermic

What is the term used to describe the regulation of body temperature through the behavioral use of temperature gradients in the environment.

Endothermic organisms can perform at high levels of speed and endurance under a variety of environmental conditions.

1. Speed of the nervous system increases 1.8 times with every 10 decrees C.

2. Speed and strength of muscle contractions increase 3 times with every 10 degrees C.

3. Endurance is greatly enhanced due to the highly developed circulatory and respiratory systems.

List the three advantages of endothermy

Endothermy is energetically costly.

1. Endothermic organisms must have a continuous high levels of energy and nutrients and oxygen. Endothermic birds typically use 20-30 times more energy than a similar sized ectothermic reptile.

2. Endotherms must be larger and/or have extra insulation such as hair or feathers to help maintain their body temperature

List two costs of endothermy

This results in extremely high blood pressure and the potential for aortic rupture

Birds hearts are generally more efficient than mammal hearts, meaning they can pump more blood per beat. However, this ability comes at a cost. What is that cost?

Grinding food

What is the purpose of the muscular ventriculus

Nictitating membrane

What is the name of the third eyelid that is usually very thin and transparent?

1. Large anterior/posterior ear flaps that regulate the size of the ear opening (funnel)

2. Auricular feathers that direct sound to the ear

List two morphological characteristics of nocturnal birds that allow them to have better hearing than most other birds.

1. Detecting stimuli on the skin

2. detecting muscle tension

3. Detecting feather movement

List 3 types of stimulation that are detected by mechanoreceptors in birds.

1. Communicating personal info (e.g. species, age, sex, status)

2. Establishing and maintaining territory

3. Attracting mates

List three uses of vocalizations

Songs: Long, frequently complex vocalizations produced by males. Used for maintaining territory and for attracting females. Some species produce only a single song, while other species can produce 100s of songs.

Calls: Short, relatively simple vocalizations produced by either sex. Used to communicate a wide variety of messages that warn of danger or allow individuals to maintain contact with each other (distress calls, warning calls, flight calls, feeding calls, nest calls, flock calls).

What is the difference between a song and a call?

Syrinx

What is the name of the structure that produces a bird’s vocalizations

Migration

The predictable directional movement of large numbers of a species from one location to another is called what?

Stopovers

High quality habitats that can be used to rest and refuel during migration are called what?

1. Sun

2. Stars

3. Geomagnetism

4. Odors

List four environmental cues that birds use to navigate

1. Migration requires huge amounts of fuel

2. Birds may be susceptible to predation during migration

List two costs associated with migration

1. They are avoiding predation from gulls and hawks

2. they are taking advantage of cooler temperatures

List two reasons why many birds migrate at night rather than during the day

1. Enhanced foraging

2. Safety from predation

3. Opportunities to learn from more experienced individuals

List three benefits that are provided to individuals in stable, long-term flocks

Territory

wWhat is an area called that is aggressively defended against intruders from the same or a different species for the purpose of maintaining exclusive use of the area and the resources it contains

1. Increased aggression to maintain personal space

2. Increased competition for resources

List two costs associated with flocking behavior

Life-History traits

Fundamental characteristics of species that directly relate to survival and reproduction are known as what?

1. Genetic information from two parents

2. Necessary resources to grow and develop until it can survive on its own

What two things do offspring require from their parents?

Good-genes Hypothesis

What is the name of the hypothesis that states that females choose males based on characteristics that accurately reflect the genetic quality and health of the males

Polygyny

What is the name of the breeding system in which one male mates with multiple females?

Brood Parasitism

What is it called when a female places her eggs in another female’s nest and lets that female raise the offspring

1. Cuculiformes

2. Passeriformes

In what two orders (found in North America) does obligate brood parasitism occur?

Endothermic

Maintaining a relatively constant body temperature using metabolic processes (birds and mammals are this)

Ectothermic

Regulating body temperature through behavioral use of temperature gradients in the environment

Environmental conditions

Endothermic organisms can perform at high levels of speed and endurance under a variety of _________

1.8 times

Speed of the nervous system increases _______ with every 10 degrees C

3 times

Speed and strength of muscle contractions increase _______ with every 10 degrees C

Endurance

_________ is greatly enhanced due to the highly developed circulatory and respiratory systems

Energetically

Endothermy is_________ costly

20-30 times

Endothermic birds typically use __________ more energy than a similar sized ectothermic reptile

Larger

Endotherms must be ______ and/or have extra insulation such as hair or feathers to help maintain their body temperature

Cardiovascular and Respiratory

Major physiological changes in the ______ and _______ systems are needed in order to support the high energetic cost.

4

Bird hearts are ________ chambered

40%

However, bird hearts are approximately ______ larger than in a comparably sized mammal

Blood Pressure

Bird hearts are generally more efficient than mammal hearts. This results in extremely high ___________ and the potential for aortic rupture.

May be as little as 30 minutes

How quick can food pass through the digestive system

Large

Bird brains are generally _______ relative to their body size

Intelligence

A large brain relative to body size is a sign of _________

forebrain

Bird’s ________ is organized differently from the mammallan forebrain and this difference led to the mistaken idea that birds were not as intelligent as mammals

Great Apes

Current evidence indicates that the cognitive ability of some birds rival the ______

eyes

Birds _____ are generally very large compared to mammal’s _____

Third eyelid

Birds have a __________ that is usually thin and transparent. provides extra protection for the eye.

2.5-3

Birds generally have excellent vision and they can see details at ______ times the distance humans can

Colors

Diurnal birds can see a greater range of ______ than humans, which means that they see the world very differently from us. Specifically, birds can see ultraviolet light

cones

Birds have four types of ______ that see different wavelengths of light

Retinal oil

Birds have ___________ droplets that further enhance color vision

Laterally

The eyes of most birds are located ________ on the head

Binocular vision

This placement of the eyes restricts __________ that enhances depth perception

Magnetic field

Birds can detect the Earth’s _________

Hear

Birds probably do not ____ as well as humans

Mammalian

The avian ear is simpler than the ___________ ear

Nocturnal

__________ birds have better hearing

Mechanoreception

Birds have a variety of tactile receptors for detecting mechanical stimulation

1. Detecting stimuli on the skin

2. Detecting muscle tension

3. Detecting feather movement

4. Detecting Wing Joints position and pressure

5. Detecting movement of fluids in the semicircular canals of the ear

6. Detecting stimuli with the bill tip

7. Detecting stimuli with the tongue

8. Detecting changes in atmospheric pressure

Birds have mechanoreceptors for:

Olfactory bulb

In the past, the avian sense of smell was underestimated due to the relatively small size of the __________ in the brains of most avian groups

1. Communicating personal info

2. Establishing and maintaining territory

3. Establishing and maintaining social hierarchies

4. Maintaining social contact

5. Attracting mates

6. Warning of danger

Vocalizations are used for a wide variety of purposes:

duration and function

Vocalizations can be classified as songs or calls based on _______ and ________

Song

Long, frequently complex vocalizations produced by males. Used for maintaining territory and for attracting females. Some species produce only a single song while other species can produce 100s of songs.

Calls

Short, relatively simple vocalizations produced by either sex. Used to communicate a wide variety of messages that warn of danger or allow individuals to maintain contact with each other

Frequencies

Vocalizations can be classified as whistles or harmonics based on the number of simultaneous frequencies produced

Whistles

A single frequency produced at any given time

Harmonics

Multiple frequencies produced simultaneously

Short vocalizations

___________ with harmonics covering a wide range of frequencies are easy to locate and may be used when a bird wishes to communicate its location

Long, high-pitched vocalizations

__________________ that are whistles or have harmonics covering a narrow range of frequencies are used in alarm calls that are given when a bird does not want to give away its location to a potential predator

Genetically programmed

In most orders of birds, vocalizations are ______________ and emerge fully formed regardless of whether the bird has previously heard the call. Most of these orders have relatively simple vocalizations

Learned

In the Passeriformes, Apadiformes, and Psittaciformes (Parrots), vocalizations must be ____________

Migration

_________ predictable directional movements of large numbers of a species from one location to another

Fuel

Migration requires huge amounts of _______

Predation

Birds may be susceptible to _______ during migration

Hormones

___________ prepare a bird morphologically, physiologically, and behaviorally for migration

Environmental cues

____________ such as photoperiod, and to a lesser extent temperature, are partially responsible for regulating these hormone levels

Social behaviors

All _________ are probably selfish in nature

Aggressive interactions

Social rank is established through __________

Flocking behavior

__________ may be nothing more than a casual aggregation of individuals at a clumped resource

Enhanced foraging, Safety from predation, opportunities to learn from more experienced individuals

Stable, long-term flocks may provide a number of potential benefits:

Males

As a general rule, _______ are not considered to be particularly selective about their mates.

Polyandry

A stable relationship in which one female mates with multiple mates

Monogamy

A stable relationship between one male and one female

Cooperative breeding

Individuals working together to raise offspring that may not be their own.

Intraspecific brood parasitism

A female placing her eggs in the nest of another individual of the same species