Concepts

All (163)Explore Concept Graph

163 concepts

theory

climate change effects on species interactions

The framework that climate affects species abundances and distributions both directly through physiological effects and indirectly through effects on multi-trophic species interactions

climate91 papers
theory

early-life trade-offs

The concept that organisms face competing demands for limited resources during development that create trade-offs between different fitness components

population ecology45 papers
theory

frequency-dependent selection

Selection where individual fitness depends on the local frequency rather than global frequency, creating population structure with groups varying in genetic and phenotypic composition

population ecology41 papers
theory

population dynamics

Changes in population size and structure over time driven by vital rates and environmental factors

population ecology41 papers
theory

nutritional niche partitioning

The concept that co-occurring species occupy distinct positions in multidimensional nutrient space to minimize competition and facilitate coexistence

community ecology38 papers
theory

local adaptation

An evolutionary process in which a population evolves to become more suited to its local environment through natural selection, resulting in higher fitness in the home environment compared to individu...

evolution37 papers
theory

fitness consequences

effects of behavioral or life history decisions on individual reproductive success and survival

population ecology30 papers
theory

time allocation tradeoff

The finite time and energy budget forcing organisms to trade off between competing activities like foraging and vigilance

general ecology28 papers
theory

nutrient limitation

Growth limitation of organisms due to insufficient availability of essential nutrients like nitrogen or phosphorus

general ecology25 papers
theory

metapopulation structure

The spatial arrangement and connectivity of subpopulations across a landscape that influences local population dynamics

population ecology23 papers
theory

evolutionary rescue

A process by which adaptive evolutionary change occurs sufficiently rapidly to counteract a decline in population size under initially unfavorable conditions

evolution20 papers
theory

gene coalescence

Statistical method for recognizing evolutionarily independent lineages based on genealogical patterns in molecular data

molecular20 papers
theory

keystone species

A species that has a disproportionately large effect on its environment relative to its abundance and whose presence/absence significantly affects ecosystem structure and function

community ecology20 papers
theory

hillslope similarity

Classification approach to identify hillslopes with similar hydrologic behavior based on physical and dynamic characteristics

hydrology18 papers
theory

optimal foraging theory

Animals adopt a foraging strategy that provides the most benefit (energy) for the lowest cost

population ecology18 papers
theory

kin selection

Natural selection that favors behaviors that benefit relatives, even at a cost to the individual performing the behavior

evolution16 papers
theory

animal personality

Consistent individual differences in behaviour across time and contexts, concept known as animal personality, behavioural types, temperament or coping styles

general ecology12 papers
theory

behavioral syndromes

Correlations between multiple repeatable, individually distinct behaviors that form consistent behavioral patterns across situations

population ecology12 papers
theory

maximum entropy theory of ecology

Theory that predicts patterns of distribution, abundance, and energetics using instantaneous values of community state variables including total area, total abundance, total species richness, and tota...

community ecology11 papers
theory

Metabolic Theory of Ecology

Theory providing mass-metabolism scaling rules that relate metabolic rate to organism mass through allometric relationships

community ecology7 papers
theory

Theory of Island Biogeography

Framework predicting that larger islands have more species at equilibrium since extinction rates decline and colonization rates increase with increased area, and islands at greater distance from mainl...

community ecology6 papers
theory

inclusive fitness

Fitness benefits that include both direct fitness (individual's own reproductive success) and indirect fitness (fitness gained by helping relatives reproduce), weighted by coefficient of relatedness

evolution5 papers
theory

local resource competition

Theory suggesting that offspring sex ratios might vary according to maternal condition, hence females should vary the sex of their offspring according to their ability to physically invest in their of...

population ecology5 papers
theory

resilience

The ability of a system to change but maintain its basic attributes; a resilient forest stand subjected to disturbance will return to conditions similar to those present prior to the disturbance but m...

general ecology5 papers
theory

functionally referential communication

Signals that meet criteria of stimulus-class specificity and contextual independence, where alarm calls are said to be functionally referential when there is tight association between predator type an...

evolution4 papers
theory

honest signaling

Signaling system where the signal reliably indicates the quality or quantity of rewards available to the receiver

community ecology4 papers
theory

ideal free distribution

Theory that animals distribute themselves among habitat patches in proportion to resource availability, with high-quality patches becoming occupied first and animals moving to lower-quality patches as...

population ecology4 papers
theory

motivation-structure rules

Morton's theory that physical behaviors and acoustic signals are associated, with aggressive behaviors linked to noisy, low-frequency sounds and submissive behaviors to higher-frequency pure tones

general ecology4 papers
theory

niche breadth

The range of resources or interaction partners utilized by a species, in this context referring to the diversity of flower visitors to a plant species

community ecology4 papers
theory

source-sink dynamics

Some environments will be resource rich and produce a high amount of offspring (sources) while other environments will be resource low and produce a low amount of offspring (sinks)

population ecology4 papers
theory

Hardy-Weinberg equilibrium

A principle stating that allele and genotype frequencies remain constant in a population under certain conditions

population ecology3 papers
theory

Neutral Theory of Biodiversity

Theory asserting that plant-pollinator interactions are neutral, random processes based on species abundances without considering traits or competitive dynamics

community ecology3 papers
theory

allometric relationships

Mathematical relationships that describe how tree dimensions and biomass scale with each other

general ecology3 papers
theory

ecology of fear

The concept that predator-prey interactions extend beyond direct predation and can influence prey behavior and habitat use through perceived predation risk

community ecology3 papers
theory

energy tradeoffs

Breeding birds must balance energy allocation between reproduction and survival, with parasites forcing energy towards immune response rather than reproductive traits

general ecology3 papers
theory

expectancy-value theory

methodological3 papers
theory

genetic constraints

Limitations on evolutionary divergence imposed by genetic architecture and patterns of genetic covariation

evolution3 papers
theory

marginal value theorem

Theory stating that foragers will leave a patch after the quality of the patch drops below the average quality of the overall habitat

general ecology3 papers
theory

optimal foraging theory

Theory stating that pollinator visitation rates are higher in areas of higher floral density while in sparse populations pollinators switch between plants less frequently

community ecology3 papers
theory

resource allocation

The distribution of limited resources among competing physiological functions such as growth, reproduction, and defense

population ecology3 papers
theory

threshold elemental ratios

The hypothesis that disposing of excess dietary nutrients imposes a growth cost on organisms, creating hump-shaped relationships with diet stoichiometry

biogeochemistry3 papers
theory

trade-offs

Situations where time spent on one activity reduces time available for other activities

general ecology3 papers
theory

Optimal Defense Theory

general ecology2 papers
theory

best of a bad lot mechanism

Paedomorphosis becomes the preferred life strategy when growing conditions such as prey abundance, water temperature, and population density are poor, so individuals opt to cut losses and become sexua...

evolution2 papers
theory

condition dependence

The concept that signal production and structure depend on an individual's health status and condition

behavioral ecology2 papers
theory

demographic compensation

Population response where decreases in fitness due to other factors are offset by increases in another demographic parameter

population ecology2 papers
theory

demographic social roles

The idea that individuals of different age-sex categories contribute differently to social structure and cohesion

population ecology2 papers
theory

energy balance theory

Process-based framework for understanding drivers of thermal offsets and thermal coupling strengths in leaves based on energy budget parameters

climate2 papers
theory

faunal elements

Biogeographic classification of species based on their broader distributional affinities and evolutionary origins

biogeography2 papers
theory

foundation species

Species that define ecosystems and provide critical habitat structure, where big sagebrush is a foundation species in steppe ecosystems of western North America

community ecology2 papers