| Term | Definition |
|---|---|
| audible signals | Communication through sound that can be perceived by hearing. |
| behavioral response | A change in an organism's actions or conduct in reaction to changes in its internal or external environment. |
| bird songs | Vocalizations produced by birds used for communication, territorial defense, and mate attraction. |
| chemical signals | Communication through chemical substances that can be perceived by smell or taste. |
| colony behavior | Coordinated behavior of insects living together in organized groups with specialized roles. |
| cooperative behavior | Behavior in which organisms work together in ways that benefit the group and may increase individual fitness. |
| differential reproductive success | Variation in the number of offspring produced by different individuals, leading to differences in genetic contribution to future generations. |
| diurnal activity | Behavioral pattern in which an organism is active primarily during daytime hours. |
| dominance | A behavioral or social status indicating an organism's rank or authority within a group. |
| electrical signals | Communication through electrical impulses that can be perceived by specialized receptors. |
| fight-or-flight response | A physiological response that prepares an organism to either confront or escape from a perceived threat. |
| fitness | An organism's ability to survive and reproduce successfully, passing its genes to the next generation. |
| flock behavior | Coordinated movement and action of a group of birds flying together. |
| herd behavior | Coordinated movement and action of a group of animals of the same species. |
| innate behaviors | Behaviors that are genetically determined and performed without prior learning or experience. |
| kin selection | The process by which organisms increase their fitness by helping relatives survive and reproduce, even at a cost to themselves. |
| kinesis | A non-directional movement response of an organism that changes in rate based on stimulus intensity. |
| learned behaviors | Behaviors that are acquired through experience, observation, or training rather than being genetically determined. |
| natural selection | A major mechanism of evolution in which individuals with more favorable phenotypes are more likely to survive and reproduce, passing advantageous traits to subsequent generations. |
| nocturnal activity | Behavioral pattern in which an organism is active primarily during nighttime hours. |
| pack behavior | Coordinated behavior of animals living and hunting together as a group. |
| parent and offspring interactions | Behaviors and communication between parents and their young that affect survival and development. |
| photoperiodism | A physiological response in plants to changes in the length of day and night, affecting processes like flowering and dormancy. |
| phototropism | A directional growth response in plants toward or away from a light source. |
| physiological response | A change in an organism's internal body functions or processes in reaction to changes in its internal or external environment. |
| plant responses to herbivory | Behavioral or physiological mechanisms by which plants respond to damage or feeding by herbivorous organisms. |
| population | A group of organisms of the same species living in the same geographic area. |
| predator warning | A behavioral or physiological response in which an organism communicates the presence of danger to other organisms. |
| predatory warnings | Signals or behaviors used by organisms to alert others to the presence of a predator. |
| reproductive success | An organism's ability to produce viable offspring that survive and reproduce. |
| schooling behavior | Coordinated movement and action of a group of fish swimming together. |
| signaling behaviors | Behaviors that organisms use to communicate information to other organisms through various mechanisms. |
| swarming behavior | Coordinated movement of a large group of insects or animals moving together. |
| tactile signals | Communication through touch that can be perceived by physical contact. |
| taxis | A directed movement response of an organism toward or away from a stimulus. |
| territorial marking | Behavior in which organisms use signals or physical marks to indicate and defend their territory. |
| territory | An area defended by an organism or group of organisms against others of the same or different species. |
| visual signals | Communication through light, color, or movement that can be perceived by sight. |
| Term | Definition |
|---|---|
| abiotic reservoirs | Non-living components of ecosystems that store matter, such as atmosphere, soil, and water. |
| ammonification | The process by which decomposers break down organic nitrogen compounds into ammonia. |
| asexual reproduction | Reproduction that produces offspring genetically identical to the parent without the fusion of gametes. |
| assimilation | The process by which organisms take up and incorporate nutrients into their biological molecules. |
| autotrophs | Organisms that capture energy from physical or chemical sources in the environment and convert it into organic compounds to fuel their own growth and metabolism. |
| biogeochemical cycles | Cycles that move matter and nutrients between biotic and abiotic reservoirs in ecosystems. |
| biomass | The total mass of living organisms in a population or trophic level. |
| biomes | Large geographic areas with similar climate, vegetation, and animal life. |
| biotic reservoirs | Living organisms and organic matter that store matter within ecosystems. |
| carbon cycle | The cycle involving the movement of carbon atoms through the biosphere, atmosphere, and organisms. |
| carnivores | Heterotrophs that obtain energy by consuming other animals. |
| cellular respiration | The metabolic process by which cells break down biological macromolecules to release energy and synthesize ATP. |
| chemosynthetic organisms | Autotrophs that capture energy from inorganic chemical compounds in their environment, independent of sunlight. |
| combustion | The burning of organic matter or fossil fuels, which releases carbon dioxide into the atmosphere. |
| community | A group of interacting populations of different species that live in the same area and change over time based on interactions between those populations. |
| condensation | The process by which water vapor cools and changes into liquid form in the atmosphere. |
| conservation of matter | The principle that matter is neither created nor destroyed but is recycled through biogeochemical cycles. |
| decomposer | Organisms, such as bacteria and fungi, that break down dead organic matter and return nutrients to the ecosystem. |
| decomposition | The process by which decomposers break down dead organic matter, releasing carbon dioxide and nutrients. |
| denitrification | The process by which soil microorganisms convert nitrate back into nitrogen gas, returning it to the atmosphere. |
| ecosystem | A community of living organisms interacting with each other and their physical environment. |
| ecosystem disruption | A disturbance to the normal functioning and balance of an ecosystem caused by changes in environmental factors. |
| ectotherms | Organisms that lack efficient internal mechanisms for regulating body temperature and rely on behavioral or environmental factors to regulate their temperature. |
| endotherms | Organisms that use thermal energy generated by their own metabolism to maintain a relatively constant body temperature. |
| energy availability | The amount of energy accessible to organisms in an ecosystem, which can change based on factors like sunlight or food resources. |
| energy flow | The movement of energy through an ecosystem from the sun through producers and consumers to decomposers. |
| energy storage | The accumulation of energy in an organism, resulting from a net gain of energy that can be used for growth and reproduction. |
| evaporation | The process by which water changes from liquid to gas and enters the atmosphere. |
| food chain | A linear sequence showing the transfer of energy from one organism to the next through feeding relationships. |
| food web | A network of interconnected food chains showing multiple feeding relationships in an ecosystem. |
| herbivores | Heterotrophs that obtain energy by consuming plants and other autotrophs. |
| heterotrophs | Organisms that obtain energy by consuming organic matter derived from autotrophs or other organisms. |
| homeostasis | The maintenance of stable internal environmental conditions in an organism despite external and internal changes. |
| hydrologic cycle | The cycle involving water movement and storage through evaporation, condensation, precipitation, and transpiration. |
| matter cycles | The movement and recycling of chemical elements and compounds between organisms and the physical environment. |
| metabolism | The sum of all chemical reactions in an organism that produce energy and build or break down molecules. |
| nitrification | The process by which soil microorganisms convert ammonia into nitrite and nitrate. |
| nitrogen cycle | The cycle involving the movement of nitrogen between the atmosphere, soil, and organisms through various microbial processes. |
| nitrogen fixation | The process by which nitrogen gas from the atmosphere is converted into ammonia by microorganisms. |
| omnivores | Heterotrophs that obtain energy by consuming both plants and animals. |
| phosphorus cycle | The cycle involving the movement of phosphorus through soil, organisms, and water in ecosystems. |
| photosynthesis | The series of reactions that use carbon dioxide, water, and light energy to produce carbohydrates and oxygen, allowing organisms to capture and store energy from the sun. |
| photosynthetic organisms | Autotrophs that capture energy from sunlight and convert it into chemical energy stored in organic compounds. |
| population | A group of organisms of the same species living in the same geographic area. |
| population size | The total number of individual organisms of the same species in a population at a given time. |
| precipitation | Water falling from clouds to Earth's surface as rain, snow, sleet, or hail. |
| primary consumer | An organism that feeds directly on producers; a herbivore. |
| primary productivity | The rate at which photosynthetic organisms capture solar energy and convert it into organic matter in an ecosystem. |
| producer | Organisms, primarily plants and photosynthetic organisms, that convert light energy into chemical energy through photosynthesis. |
| quaternary consumer | An organism that feeds on tertiary consumers; a carnivore at the fourth trophic level. |
| reproductive diapause | A period of suspended or delayed reproduction in response to unfavorable environmental conditions or limited energy availability. |
| reproductive strategies | Different approaches organisms use to reproduce in response to environmental conditions and energy availability. |
| scavengers | Heterotrophs that obtain energy by consuming dead organisms or organic waste. |
| secondary consumer | An organism that feeds on primary consumers; a carnivore or omnivore at the second trophic level. |
| sexual reproduction | Reproduction involving the fusion of gametes from two parents, producing genetically diverse offspring. |
| tertiary consumer | An organism that feeds on secondary consumers; a carnivore at the third trophic level. |
| transpiration | The process by which water is released from plants into the atmosphere. |
| trophic level | A position in a food chain or food web occupied by organisms that obtain energy in the same way, including producers, consumers, and decomposers. |
| trophic pyramid | A diagram representing the relative amounts of energy or biomass at each trophic level in an ecosystem. |
| weathering | The process by which rocks break down, releasing minerals such as phosphate into soil and water. |
| Term | Definition |
|---|---|
| adaptation | A genetic variation that is favored by natural selection and manifests as a trait providing an advantage to an organism in a particular environment. |
| birth rate | The number of new individuals produced per unit time in a population. |
| death rate | The number of individuals that die per unit time in a population. |
| exponential growth | Population growth that occurs without limiting constraints, resulting in a population that increases at an accelerating rate over time. |
| per capita growth rate | The rate at which a population grows per individual organism in the population. |
| population growth dynamics | The changes in population size over time, determined by the rates at which individuals are born and die. |
| population size | The total number of individual organisms of the same species in a population at a given time. |
| Term | Definition |
|---|---|
| carrying capacity | The maximum population size of a species that an ecosystem can sustain indefinitely based on available resources. |
| density-dependent factors | Limiting factors whose effects on population growth increase as population density increases, such as disease, competition, and predation. |
| density-independent factors | Limiting factors that affect population growth regardless of population density, such as weather, natural disasters, and seasonal changes. |
| logistic growth model | A model of population growth that accounts for limited resources, showing how population growth slows as it approaches carrying capacity. |
| resource availability | The quantity and accessibility of resources in an environment that support population growth and survival. |
| Term | Definition |
|---|---|
| commensalism | A symbiotic relationship where one organism benefits while the other organism is neither helped nor harmed. |
| community | A group of interacting populations of different species that live in the same area and change over time based on interactions between those populations. |
| community structure | The composition and organization of a community, determined by the types and relative abundances of populations and their interactions. |
| competition | An interaction between populations where organisms compete for the same limited resources, negatively affecting both populations. |
| mutualism | A symbiotic relationship where both organisms benefit from the interaction. |
| niche partitioning | The division of resources among species that allows multiple populations to coexist by utilizing different aspects of their environment. |
| parasitism | A symbiotic relationship where one organism (parasite) benefits while the other organism (host) is harmed. |
| population | A group of organisms of the same species living in the same geographic area. |
| population dynamics | Changes in population size and structure over time, influenced by interactions with other populations and environmental factors. |
| predation | An interaction where one organism (predator) hunts and consumes another organism (prey). |
| predator/prey interactions | Relationships between populations where one organism (predator) hunts and consumes another (prey), influencing population dynamics and energy flow. |
| Simpson's Diversity Index | A quantitative measure of species diversity that accounts for both the number of species and the evenness of their abundance in a community. |
| species composition | The identity and relative abundance of different species present in a community. |
| species diversity | A measure of the variety of species in a community, accounting for both the number of species and their relative abundance. |
| symbiosis | A close, long-term relationship between two different species living together. |
| trophic cascades | Ecological changes triggered by the addition or removal of top predators, affecting multiple levels of the food chain. |
| Term | Definition |
|---|---|
| abiotic factors | Non-living physical and chemical components of an ecosystem, such as temperature, light, water, and soil. |
| biotic factors | Living organisms and biological components of an ecosystem, including animals, plants, fungi, and microorganisms. |
| ecosystem | A community of living organisms interacting with each other and their physical environment. |
| ecosystem collapse | The sudden loss of ecosystem structure and function, often resulting from the removal of a keystone species. |
| ecosystem diversity | The variety of different ecosystems and the range of species and ecological processes within them. |
| keystone species | A species whose presence or absence has a disproportionate effect on the structure and function of an ecosystem relative to its abundance. |
| producer | Organisms, primarily plants and photosynthetic organisms, that convert light energy into chemical energy through photosynthesis. |
| resilience | The ability of an ecosystem to withstand and recover from environmental changes or disturbances. |
| Term | Definition |
|---|---|
| adaptation | A genetic variation that is favored by natural selection and manifests as a trait providing an advantage to an organism in a particular environment. |
| biogeographical studies | Scientific research that examines the distribution of organisms and ecosystems across different geographic regions and how they change over time. |
| biomagnification | The process by which the concentration of a substance, such as a toxin or pollutant, increases in organisms at higher trophic levels in a food chain. |
| competitors | Organisms that vie for the same resources, such as food, water, or space. |
| continental drift | The movement of Earth's continents over geological time, which alters the distribution of habitats and ecosystems. |
| ecosystem distribution | The geographic locations and patterns where different ecosystems are found across the biosphere. |
| ecosystem dynamics | The interactions and changes that occur within an ecosystem, including relationships between species and how populations respond to environmental changes. |
| ecosystem structure | The physical organization and composition of an ecosystem, including the arrangement of organisms, habitats, and abiotic factors. |
| El Niño | A meteorological phenomenon characterized by warming of ocean temperatures in the Pacific, causing significant changes in global weather patterns and ecosystems. |
| environmental pressure | External environmental conditions or stressors that affect the survival and reproduction of organisms in a population. |
| eutrophication | The process by which excessive nutrients, particularly nitrogen and phosphorus, accumulate in a water body, leading to excessive algal growth and oxygen depletion. |
| extinction | The permanent disappearance of a species from Earth, occurring when all individuals of that species die. |
| genetic variation | Differences in DNA sequences and alleles that exist within a population. |
| geological activity | Physical processes and events related to Earth's structure and composition, such as volcanic eruptions, earthquakes, and continental drift, that can alter ecosystems. |
| global climate change | Long-term shifts in Earth's climate patterns and average temperatures that affect ecosystems worldwide. |
| habitat change | Alterations in the physical and biological conditions of a habitat that affect the organisms living there. |
| heterozygote advantage | A situation where the heterozygous genotype has higher relative fitness than either homozygous genotype. |
| heterozygous genotype | A genotype with two different alleles for a particular gene. |
| homozygous dominant genotype | A genotype with two copies of the dominant allele for a particular gene. |
| homozygous recessive genotype | A genotype with two copies of the recessive allele for a particular gene. |
| invasive species | A species that is introduced to a new environment, either intentionally or unintentionally, and can exploit available niches or outcompete native species for resources. |
| meteorological activity | Atmospheric and weather-related phenomena, such as storms, precipitation patterns, and climate events, that influence ecosystem conditions. |
| mutations | Random changes in DNA sequences that create new genetic variations in populations. |
| native species | Species that naturally occur and belong in a particular ecosystem. |
| niche | The specific role and position a species has in its environment, including the resources it uses and the conditions it requires to survive. |
| outcompete | To surpass other organisms in competition for limited resources, often resulting in reduced survival or reproduction of the competing species. |
| predators | Organisms that hunt and consume other organisms for food. |
| relative fitness | The measure of an organism's reproductive success compared to other individuals in the population. |
| selection | The process by which certain traits become more or less common in a population based on their effect on survival and reproduction. |
| trait | A characteristic or feature of an organism that is determined by its genes and expressed in its phenotype. |