Lecture 15: Breeding in Birds 1

These flashcards cover key vocabulary and concepts related to longevity and life history traits in birds, as explored in the lecture.

Life history traits

Fundamental species traits that determine the timing of important life events from birth to death.

Trade-offs

A condition where an increase in the performance of one trait causes a decrease in another due to limited resources.

Interspecific variation

Differences in traits among different species, such as longevity within birds.

Survivorship curves

Graphs that represent the number of individuals surviving at each age in a population.

Type I survivorship curve

Characterized by low mortality rates in young individuals, commonly seen in species like whales and humans.

Type II survivorship curve

Characterized by constant mortality rates throughout life, examples include gulls.

Type III survivorship curve

High mortality rates in young individuals, an example includes desert shrubs.

Longevity

The lifespan of an organism; maximum lifespan varies by species, particularly in birds.

Parental investment

The amount of time and resources devoted by parents to raising their offspring.

Maximum longevity

The longest recorded lifespan of a species in ideal conditions.

How does body size influence avian longevity?

Larger bird species generally exhibit longer lifespans due to lower metabolic rates per unit mass and often reduced predation risk compared to smaller species.

How does parental investment influence avian longevity?

Species with higher parental investment per offspring (e.g., fewer, better-cared-for young) tend to have longer lifespans, reflecting a 'slow' life history strategy where parental survival is also prioritized.

How does migratory behavior influence avian longevity?

Migratory bird species often have shorter average lifespans than non-migratory species due to the increased energetic demands, predation risks, and stress associated with long-distance travel.

What are the global patterns of avian longevity?

Avian longevity tends to be greater in stable, resource-rich environments (e.g., tropical forests) and generally shorter in harsher, more unpredictable high-latitude environments or areas with intense seasonality.

How does environmental stability impact global avian longevity patterns?

Environments with consistent resources and less climatic variability (e.g., tropical zones) favor slower life histories and increased longevity in birds, as individuals face fewer unpredictable challenges.