Ecology: Behavior, Population, and Community Dynamics

Comprehensive vocabulary flashcards covering behavior, population ecology, life history strategies, community interactions, and ecosystem dynamics.

Ecology

The scientific study of the interactions between living organisms and their environments.

Organismal Ecology

The study of morphological, physiological, and behavioral adaptations that enable individuals to live in specific habitats.

Population Ecology

The study focused on the number of individuals in an area and how and why population size changes over time.

Community Ecology

The study of the processes driving interactions between different species in an area, as well as their ecological consequences.

Ecosystem Ecology

The study of the storage and movement of nutrients and energy among organisms and the surrounding atmosphere, soil, and water.

Behavior

How organisms interact with other organisms and their environment.

Innate Behaviors

Behaviors that have a strong genetic component, are instinctive, and do not require prior experience.

Reflex Action

An involuntary and rapid motor response to a stimulus that does not necessarily require a complete neural arc to a central processing unit.

Fixed Action Pattern

A predictable series of movements elicited by a key stimulus that continues to completion even if the triggering stimulus is removed.

Learned Behaviors

Dynamic, flexible behaviors resulting from environmental conditioning and experience that can be altered according to changes in the environment.

Imprinting

A form of learning in which a very young animal rapidly fixes its attention on the first object with which it has visual, auditory, or tactile experience and thereafter follows that object.

Adaptive Behavior

Any behavior that contributes directly or indirectly to an individual's reproductive success and is thus subject to natural selection.

Migration

The long-range, typically seasonal movement of animals stimulated by photoperiod, weather conditions, or other external cues.

Hibernation

A state of long-term reduced metabolism that allows animals to conserve energy to survive adverse weather conditions or food scarcity.

Foraging

The suite of behaviors an organism uses to search for, acquire, and utilize sources of energy and nutrients.

Courtship Displays

Specialized behavioral patterns that result in mate selection, copulation, and eventual reproduction.

Social Behavior

The suite of interactions occurring between two or more individuals, usually of the same species, ranging from simple attraction to complex societies with division of labor.

Reciprocal Altruism

A cooperative behavior occurring between unrelated individuals in groups where individuals can recognize each other and reciprocate benefits, while cheaters can be punished.

Kin Selection

An evolutionary strategy that promotes cooperation by increasing an individual's inclusive fitness through aiding genetic relatives.

Communication

The transfer of information from one organism or group to another via visual, auditory, electrical, chemical, or mechanical signals that affects the receiver's current or future behavior.

Circadian Clocks

The internal molecular mechanism that controls circadian rhythms—the physical, mental, and behavioral cycles an organism experiences over a 24-hour cycle.

Biogeography

The scientific study of the geographic distribution of living organisms and the abiotic factors that influence that distribution.

Endemic Species

A species that is naturally restricted and found only within a specific, localized geographic area.

Generalist Species

A species capable of living and thriving across a wide variety of geographic areas and ecological conditions.

Population Size ($N$)

The total count of individual organisms belonging to the same species in a defined population.

Population Density

The number of individual organisms belonging to a population per unit of area or volume.

Quadrat

A square frame used by ecologists to isolate a standard area for sampling the population size and density of immobile or sessile organisms.

Mark and Recapture

A field sampling technique used by ecologists to determine the overall population size of mobile wildlife.

Species Dispersion Patterns

The spatial relationships showing how individuals in a population are arranged within their habitat at a specific time (clumped, uniform, or random).

Demography

The statistical study of population changes over time, including measurements of birth rates, death rates, and life expectancies.

Life Table

A demographic tabulation dividing a population into age groups to show mortality probabilities, survival rates, and life expectancies at each interval.

Carrying Capacity ($K$)

The maximum population size of a species that can be sustained by the resources available in a given environment.

Logistic Growth Model

A population growth model that incorporates environmental resistance and carrying capacity ($K$), calculated as $\frac{dN}{dT} = rN\left(\frac{K - N}{K}\right)$.

Density-Independent Factors

Environmental factors such as weather extremes, freezes, and natural disasters that affect population mortality regardless of population density.

Density-Dependent Factors

Biotic factors such as competition, predation, waste buildup, and disease whose regulatory effect on mortality and fecundity intensifies as population density increases.

Demographic Transition

A demographic shift occurring when female empowerment, education, and labor access lead to delayed childbearing and smaller families, ultimately slowing population growth.

Survivorship Curves

Graphical curves showing the number of surviving individuals over relative age, categorized as Type I (late mortality), Type II (constant mortality), and Type III (early mortality).

Fecundity

The potential reproductive capacity of an individual organism within a population.

Semelparity

A reproductive strategy in which an individual organism reproduces only once during its lifetime and then dies shortly thereafter.

Iteroparity

A reproductive strategy characterized by multiple, repeated reproductive events across an individual organism's lifetime.

$K$-Selected Species

Species adapted to stable, predictable environments near carrying capacity ($K$), characterized by late maturity, long lifespans, few offspring, and high parental investment.

$r$-Selected Species

Species adapted to unpredictable or disturbed environments that maximize intrinsic growth rate ($r$) by producing large numbers of small offspring with low parental care.

Ecological Niche

The ecological role, resource requirements, and environmental parameters an organism fulfills and occupies in its biological community.

Symbiotic Relationship

A close, long-term biological interaction between organisms belonging to two or more different species.

Mutualism

A symbiotic interaction in which both participating organisms benefit ($+/+$) from the relationship.

Amensalism

An ecological interaction where one organism is adversely harmed or inhibited while the other organism is unaffected ($-/0$).

Commensalism

A symbiotic relationship in which one species derives a benefit while the host species is neither harmed nor helped ($+/0$).

Obligate Symbiosis

A symbiotic partnership in which at least one partner relies completely on the relationship and cannot complete its life cycle alone.

Facultative Symbiosis

A symbiotic interaction in which both partners benefit from the relationship but can survive and reproduce independently.

Intraspecific Competition

Competition for shared limited resources that occurs among individuals of the same species.

Interspecific Competition

Competition for shared limited resources that occurs among individuals belonging to different species.

Exploitative Competition

Indirect competition in which organisms consume and deplete a shared, limited resource, leaving less available for others.

Interference Competition

Direct competition involving active physical confrontations or chemical warfare to exclude other organisms from resources.

Competitive Exclusion Principle

The ecological rule stating that two species competing for identical limiting resources cannot coexist indefinitely in the same ecological niche.

Resource Partitioning

The evolutionary division of environmental resources among competing species, allowing similar species to coexist by occupying distinct realized niches.

Life-Dinner Principle

The concept that natural selection acts more strongly on prey than predators because the prey faces loss of life, whereas the predator only risks losing a meal.

Aposematic Coloration

Distinctive warning coloration used by poisonous, venomous, or unpalatable prey organisms to signal their defenses to potential predators.

Batesian Mimicry

A form of mimicry where an innocuous, palatable species gains protection from predation by resembling a harmful or toxic model species.

Müllerian Mimicry

A form of mimicry in which two or more harmful, unpalatable, or toxic species evolve similar warning coloration patterns, mutually reinforcing predator avoidance.

Aggressive Mimicry

A predatory strategy where a predator or parasite mimics a harmless species or potential mate to lure and ambush its prey.

Biodiversity

The biological diversity of genetic sequences, cell types, metabolisms, life histories, phylogenetic groups, communities, and ecosystems.

Foundation Species

A species that forms the bedrock or architectural base of a community, typically possessing high biomass and providing essential habitat for numerous other organisms.

Keystone Species

A species that exerts top-down regulation and plays an outsized role in preserving community structure and biodiversity relative to its small abundance or biomass.

Ecosystem Engineer

An organism that directly or indirectly creates, substantially alters, or maintains physical habitats by modifying biotic or abiotic materials.

Intermediate Disturbance Hypothesis

The ecological principle stating that moderate frequencies or intensities of environmental disturbance foster higher species richness than either very low or very high disturbance levels.

Invasive Species

A non-native organism introduced to a novel ecosystem that establishes, spreads aggressively, and causes ecological or economic damage.

Succession

The sequential, predictable appearance and disappearance of species within an ecological community following a disturbance.

Primary Succession

The biological colonization and ecological development that takes place on newly formed or exposed substrates, such as bare rock or cooled lava, devoid of pre-existing soil.

Secondary Succession

The process of ecological re-colonization and development that occurs in an area where a disturbance destroyed existing community vegetation but left the soil intact.

Pioneer Species

The first organisms—such as hardy lichens or annual plants—to successfully colonize a barren, severely disturbed, or newly formed habitat.

Equilibrium

The steady ecological state in which organisms in a community exist in dynamic balance with each other and their abiotic surroundings.

Ecosystem Resistance

The inherent ability of an ecosystem to withstand disturbances and maintain its equilibrium state.

Ecosystem Resilience

The speed and efficiency with which an ecosystem recovers its baseline equilibrium state after suffering an environmental disturbance.

Ecology

The scientific study of the interactions between living organisms and their environments.

Organismal Ecology

The branch of ecology that studies morphological, physiological, and behavioral adaptations that enable individuals to live in specific habitats.

Population Ecology

The study of the number of individuals of a single species in an area and how and why population size changes over time.

Community Ecology

The study of the processes driving interactions between different species inhabiting a common area, as well as the ecological consequences of those interactions.

Ecosystem Ecology

The study of the storage and cycling of nutrients and the movement of energy among organisms and the surrounding atmosphere, soil, and water.

Behavior

The ways in which organisms interact with other organisms and with their physical environment.

Innate Behaviors

Behaviors that have a strong genetic component, are instinctive, and do not require prior experience to perform.

Reflex Action

An involuntary and rapid response to a stimulus that does not necessarily require a complete neural circuit to a central processing unit.

Fixed Action Pattern

A predictable series of movements elicited by a specific cue (or key stimulus) that continues to completion even if the stimulus is removed during the behavior.

Learned Behaviors

Behaviors resulting from environmental conditioning that are flexible, dynamic, and alterable in response to changes in the environment.

Learning

A long-term change in behavior that occurs as a direct result of experience.

Imprinting

A specialized form of learning in which a very young animal fixes its attention on the first object with which it has visual, auditory, or tactile experience and thereafter follows that object.

Adaptive Behavior

Any behavior that contributes directly or indirectly to an individual's reproductive success, making it subject to the forces of natural selection.

Migration

The long-range movement of animals, typically seasonal and triggered by external cues such as photoperiod and weather conditions.

Hibernation

A state of long-term reduced metabolism used by animals to conserve energy and survive hostile conditions such as freezing temperatures or food shortages.

Foraging

The suite of behaviors an organism employs to search for, acquire, and utilize sources of energy and nutrients.

Courtship Displays

Specific behavioral signals and rituals designed to facilitate mate choice, resulting in mating and eventual reproduction.

Social Behavior

The suite of interactions between two or more individuals (usually of the same species) ranging from simple attraction to organized societies characterized by division of labor and cooperation.

Reciprocal Altruism

A social interaction that promotes cooperation in groups where individuals are recognizable, can reciprocate helpful acts, and can punish individuals who fail to return assistance.

Kin Selection

An evolutionary strategy favoring cooperation when individuals increase their inclusive fitness (transmitting shared genes by descent) by assisting genetic relatives.

Communication

The transmission of information from one organism or group to another via visual, auditory, electrical, chemical, or mechanical signals that alters the current or future behavior of the receiver.

Circadian Clocks

The central biochemical mechanism that regulates circadian rhythms, governing physical, mental, and behavioral cycles over approximately a $24$-hour period.

Biogeography

The study of the geographic distribution of living organisms and the abiotic factors (such as temperature and rainfall) that dictate their distribution.

Endemic Species

A species naturally occurring only within a single, restricted geographic location.

Generalist Species

A species capable of surviving and thriving across a wide range of geographical areas and environmental conditions.

Population Size ($N$)

The total number of individual organisms belonging to the same species in a defined area.

Population Density

The number of individuals of a population per unit of area or volume.