Ornithology exam 2 study guide - Claude

How does the avian metabolic rate compare to that of mammals and other vertebrates?

Birds have a higher metabolism than mammals and possess the highest metabolism among vertebrates, with smaller birds having higher relative metabolisms.

What is Bergmann's Rule?

An ecogeographical rule stating that warm-blooded animals living in colder climates usually have larger body sizes and masses than equivalent animals from warmer climates to help retain heat.

What is Allen's Rule?

An ecogeographical rule stating that animals adapted to colder climates tend to have shorter appendages compared to their warm-climate counterparts.

What behavioral and physiological mechanisms do birds use for temperature regulation in cold environments?

Fluffing feathers, countercurrent heat exchange, entering torpor, bill tucking, moving legs under feathers, and huddling.

What are the four major dietary/foraging categories outlined in avian feeding ecology?

Granivory (seed-eating), carnivory (meat-eating), frugivory (fruit-eating), and omnivory (consuming plant and animal matter).

What is hyperphagy?

An abnormally elevated appetite or excessive consumption of food, typically used by birds to rapidly build fat storage before migration or winter.

What is geophagy?

The deliberate ingestion of soil, clay, or earthy substances by birds to supplement minerals or bind dietary toxins.

What does Optimal Foraging Theory predict about bird behavior?

It predicts that birds will forage in ways that maximize their net energy gain per unit time while minimizing expenditure and predation risk.

What is kleptoparasitism?

A foraging strategy in which one individual opportunistically steals food or prey items captured by another bird.

What is hovergleaning?

A feeding strategy where a bird hovers mid-air to pick food items, such as insects or fruit, off foliage or surfaces.

What is underwater pursuit foraging?

A specialized feeding strategy where birds dive into water bodies and actively swim to chase and capture aquatic prey.

What is ambush/stalking foraging?

A feeding tactic in which a bird remains stationary or stalks slowly to surprise and seize unsuspecting prey.

How has nectarivory evolved in birds in relation to plants?

Nectarivory has evolved repeatedly across multiple bird families via convergent evolution, functioning as a coevolutionary mutualism for plant pollen dispersal.

What is mobbing behavior?

A cooperative defense behavior where multiple birds harass, vocalize at, or dive-bomb a predator to drive it away from the area.

What is interspecific territoriality?

Territorial defense directed by a territory-holding bird against individuals belonging to an entirely different species.

What are the three main mating systems found in birds?

Monogamy (one mate), polygyny (one male with multiple females), and polyandry (one female with multiple males).

How does social monogamy differ from genetic monogamy?

Social monogamy involves a pair that cohabits and raises offspring together, whereas genetic monogamy requires that the pair exclusively sires all offspring with no extrapair paternity.

What are extrapair copulations (EPCs)?

Copulations that occur between a socially paired bird and an individual outside of that pair bond, resulting in extrapair paternity.

What is lekking?

A mating system where males gather at a communal display ground (a lek) to exhibit courtship displays, allowing females to choose a mate.

What is avian brood parasitism?

A reproductive strategy in which a female lays her eggs in the nest of another bird (the host), relying on the host to raise the chicks.

What distinguishes bird songs from bird calls?

Songs are longer, more complex vocalizations mainly used for territory defense and mate attraction, while calls are shorter, simpler, and used for immediate coordination or alarms.

What are the five primary types of bird calls covered in avian vocal signaling?

Contact calls, alarm calls, mobbing calls, begging calls, and flight calls.

What are the key stages of song learning in birds that lack purely innate vocalizations?

Sensory acquisition phase (listening to model songs), a silent period, subsong/plastic song practice, and song crystallization.

What is the Dawn Chorus?

A period at sunrise when birds sing intensely, favored because cool, calm morning air allows sound to travel farther and dim lighting limits early foraging.

How does ritualization shape visual signaling in birds?

It modifies non-communicative ancestral behaviors (e.g., foraging, nest building, nestling feeding, aggression) into exaggerated, stylized visual displays driven by sexual selection.