Reproduction and Population Dynamics

Female Mate Choice

Influences male ornamentation evolution; can be reduced by natural selection.

Nonrandom Mating in Plants

Certain individuals preferentially mate; not random in wild plant populations.

Evolution of Sociality Drivers

Group defense, resource provision, and mate protection drive social evolution.

Kin Selection

Selection favoring relatives' reproductive success; key in eusocial evolution.

Ecological Constraints

Environmental factors limiting social evolution; influence eusociality.

Behavioral Ecology

Study of social relations within populations; part of sociobiology.

Fitness

Measure of offspring contribution to future generations; genetic success.

Anisogamy

Gamete size-based male/female designation; determines sex in organisms.

Hermaphrodite

Organism with both male and female reproductive functions.

Sexual Selection

Differences in mating success due to reproductive rate variations.

Intrasexual Selection

Competition within one sex for mating; winner mates.

Intersexual Selection

Mate choice based on specific traits; influences evolution.

Bluehead Wrasse

Species with males developing blue heads to attract females.

Slipper Limpet

Hermaphroditic species where individuals function as both sexes.

Sexual Selection Role

Shapes traits related to mating; impacts evolution.

Mate Choice Factors

Include behavior, physical traits, and fitness in selection.

Best Adapted Mating

Sexual selection doesn't guarantee best-adapted individuals mate.

Guppy Mate Choice

Female preference for brightly colored males; tradeoffs exist.

Scorpionflies Mating

Male guarding resources to attract mates; larger males more successful.

Comparative Method Experiment

Studies nonrandom mating using different species or populations.

Territory quality

Significant in sociality evolution

Lifetime reproductive success

Studied in males and females in social groups

Cooperative breeder

Florida Scrub Jay's social group structure

Helpers

Aid breeding pairs in Florida Scrub Jay groups

Cooperative breeding

Observed in Florida Scrub Jays due to limited territories

Prides

African lions live in groups for hunting and defense

Eusociality

Complex sociality with reproductive castes, e.g., ants

Comparative method

Used to study social evolution across species

Kin selection

Favors helping behaviors among related individuals

Inclusive fitness

Enhances survival and reproduction of family members

Limited breeding opportunities

Drive evolution of sociality in species

Altruistic behavior

Sacrificing for relatives' benefit in nature

Population ecology

Studies interactions of organisms with environment

Genetic influence

Affects traits and adaptations in populations

Dispersion

Pattern of spacing in a population

Mortality/Survivorship

Death rate and survival proportion in a population

Age structure

Distribution of individuals across age groups

Birth rate

Number of offspring produced per unit time

Population growth

Change in population size over time

Distribution Patterns

Different ways organisms within populations are distributed

Uniform

Evenly spaced individuals in a population

Clumped

Individuals grouped together in a population

Random

Individuals scattered randomly in a population

Desert Shrubs Distribution

Changes over time from clumped to regularly spaced

Competition

Intensifies with population density, affecting distribution patterns

Intraspecific Competition

Competition between individuals of the same species

Interspecific Competition

Competition between individuals of different species

Organism Size and Population Density

Density decreases with increasing organism size

Microclimates

Different species have preferences for temperature and climate

Tiger Beetle Species Preference

Cicindela longilabris prefers lower temperatures due to metabolic rate

Damuth's Study

Herbivorous mammal density decreases with body size increase

Self-Thinning Principle

Plant density decreases as plant size increases

Rarity & Extinction Vulnerability

Based on range, tolerance, and population size

Minimum Viable Population

Population size preventing extinction

Factors Contributing to Extinction

Include habitat alteration, hunting, pollution, and more

Resource Limitation

Increases extinction risk due to competition for limited resources

Fluctuating Equilibrium

Balance between population growth and resource availability

Dispersal

Movement of individuals into or out of a local population

Survivorship Curves

Summarize survival patterns in a population at different ages

Type I Survivorship Curve

High survivorship early on, rapid decline in old age

Age Distributions

Reflect population history, reproduction, and future growth potential.

Species Distributions and Climate Shifts

Changes in species' habitats due to climate shifts.

Population Dynamics Equation

Calculates population size based on births, deaths, immigration, and emigration.

Net Reproductive Rate (R0)

Estimates average number of offspring produced by an individual in a population.

Geometric Rate of Increase (λ)

Rate at which a population grows over a certain period.

Generation Time (T)

Average time between the birth of an individual and the birth of its offspring.

Per Capita Rate of Increase (r)

Average contribution of each individual to population growth.

Africanized Honeybees Dispersal

Rapid dispersal across South and Central America within 30 years.

Collared Doves Dispersal

Spread from Turkey to Europe post-1900, with sudden dispersal onset.

Holling's Functional Response Models

Describe feeding behavior changes with food density in predators.

Drift in Rivers and Streams

Gradual passive downstream movement in water bodies.

Spates in Rivers and Streams

Flash flood events causing downstream organism movement.

Metapopulations

Subpopulations on connected habitat patches exchanging individuals.

Alpine Butterfly Study

Marked butterflies showed dispersal between meadows.

Lesser Kestrels Study

Younger breeding individuals more likely to disperse between subpopulations.

Life Tables

Study mortality and survival patterns by recording age at death.

Static Life Table

Calculates differences in age class proportions to study mortality.

Survivorship Curve

Graphical representation of mortality and survival patterns.

Type II Survivorship Curve

Constant mortality rate throughout lifespan.

Type III Survivorship Curve

High mortality among young, high survival in few adults.

Age Distribution

Proportion of individuals in a population at different age classes.

Age Distribution Examples

Reflect population history; e.g., Type I for Dall sheep.

Rate of Increase (r)

Population size divided by time span; birth rate minus death rate.

Fecundity Schedule

Tabulation of birth rates for different age reproductive individuals.

Survivorship

Number of individuals surviving at different ages.

Phlox drummondii

Species with survivorship and fecundity schedule examples.

Sexual Reproduction

Two parents contribute genetic material to produce offspring.

Asexual Reproduction

Single parent produces genetically identical offspring.

Binary Fission

A form of asexual reproduction in bacteria

Budding

A form of asexual reproduction in yeast

Vegetative Propagation

A form of asexual reproduction in plants

Logistic Population Growth

Population growth slows as resources deplete, reaching carrying capacity

Sigmoidal Curve

S-shaped population growth curve

Carrying Capacity (K)

Maximum number of individuals an environment can support

Density-Dependent Factors

Factors like disease and competition that limit population growth

Density-Independent Factors

Factors like natural disasters that limit population growth

Galapagos Finch Study

Boag and Grant studied Geospiza fortis population dynamics

Cactus Finches

Grant and Grant studied finches' interaction with cacti

Large Offspring

Common in mammals, woody plants, and most vertebrates; produced in abundant resources

Small Offspring

Common in fish, insects, and some plants; produced in limited resources