Behavioral Ecology and Ecosystem Dynamics

Innate Behavior

Behavior that is genetically programmed; organisms are born with it and it occurs without prior experience.

Example of Innate Behavior

A spider spinning a web.

Fixed Action Pattern (FAP)

A sequence of unchangeable behaviors triggered by a specific stimulus (sign stimulus).

Example of Fixed Action Pattern

Goose rolling an egg back to its nest.

Habituation

Decreased response to a repeated, harmless stimulus.

Example of Habituation

Birds stop reacting to scarecrows.

Imprinting

Learning during a sensitive period (often irreversible).

Example of Imprinting

Ducklings following the first moving object they see.

Associative Learning

Learning to associate two stimuli.

Example of Classical Conditioning

Pavlov's dogs salivating at a bell.

Operant Conditioning

Learning through rewards and punishments.

Example of Operant Conditioning

Rat pressing a lever for food.

Social Learning

Learning by observing others.

Example of Social Learning

Young chimps watching adults use tools.

Cognition

Ability to reason, problem-solve, and use tools.

Example of Cognition

Crows bending a wire to retrieve food.

Spatial Learning

Remembering the structure of an environment.

Example of Spatial Learning

Bees recognizing landmarks around their hive.

Kinesis

Random movement in response to a stimulus (rate depends on stimulus intensity).

Example of Kinesis

Pill bugs move more in dry areas.

Taxis

Directed movement toward or away from a stimulus.

Example of Taxis

Fish swimming toward light (positive phototaxis).

Migration

Seasonal movement for resources, breeding, or climate.

Cognitive Mapping

Internal representation of spatial relationships for navigation.

Optimal Foraging Theory

Animals forage in a way that maximizes benefits (food energy) and minimizes costs (time, risk).

Agonistic Behavior

Competitive behavior related to fighting, often over resources or mates.

Altruism

Selfless behavior benefiting another at a cost to oneself.

Kin Selection

Helping relatives increases shared gene survival.

Reciprocal Altruism

Help now, get help later.

Mating Strategies

Types: Monogamy, polygamy (polyandry, polygyny), promiscuity.

Courtship Behaviors

Rituals/signals to attract mates, confirm species identity, assess mate quality.

Population

Same species, same area.

Community

Multiple populations in one area.

Ecosystem

Community + abiotic factors.

Biosphere

All ecosystems on Earth.

Desert Biome

Low rainfall, hot days, cool nights.

Tropical Rainforest

High rainfall, high biodiversity, warm year-round.

Temperate Deciduous

Seasonal changes, moderate rainfall.

Taiga (Boreal)

Cold, coniferous forests, long winters.

Tundra

Cold, permafrost, short growing season.

Temperate Grassland

Fertile soils, few trees, seasonal droughts.

Savanna

Warm, seasonal rain, grasses, scattered trees.

Coniferous Forest

Mostly conifers, cool temperatures.

Freshwater Systems

Lakes, ponds, rivers — vary with depth, flow, oxygen.

Marine Systems

Oceans — zones based on depth, light, and proximity to shore.

Population Density

Density: Number of individuals per unit area.

Population Dispersion

Dispersion: Clumped, uniform, or random.

Exponential Growth

ΔN/Δt=rmaxN

Logistic Growth

ΔN/Δt=rmaxN(K−N)/K

Carrying Capacity (K)

The maximum population size that an environment can sustain.

r-selected Species

Many offspring, little care; short life, rapid reproduction.

K-selected Species

Few offspring, much care; long life, stable environment.

Intraspecific Competition

Competition between individuals of the same species.

Interspecific Competition

Competition between individuals of different species.

Competitive Exclusion Principle

No two species can occupy the same niche; one outcompetes.

Resource Partitioning

Similar species use different resources or times.

Predation

Predator kills prey.

Herbivory

Animal eats plants.

Parasitism

Parasite benefits, host harmed.

Batesian Mimicry

Harmless mimics harmful.

Müllerian Mimicry

Two harmful species resemble each other.

Commensalism

One benefits, other unaffected.

Mutualism

Both species benefit.

Primary Ecological Succession

Begins without soil (lava flows).

Secondary Ecological Succession

Follows disturbance, soil remains (fire, flood).

Trophic Levels

Producers: Plants/algae; Primary Consumers: Herbivores; Secondary Consumers: Carnivores; Tertiary Consumers: Top predators.

Energy Pyramid

Shows energy and mass loss between levels; about 10% of energy transfers to next level.

Water Cycle

Evaporation → Condensation → Precipitation.

Carbon Cycle

Photosynthesis → Respiration → Decomposition → Fossil fuels.

Nitrogen Cycle

Nitrogen fixation → Nitrification → Assimilation → Denitrification.

Phosphorus Cycle

Rocks → Soil/water → Organisms → Decomposition.