Ecology, Community, and Conservation Biology Flashcards

Flashcards about Ecology and the Biosphere, Environmental Interactions, and Population Community Ecology, including terms, definitions, and important concepts.

Ecology

The study of how organisms interact with one another and with their physical environment.

Population

A group of individuals of the same species living in a specific area.

Ecosystem

A community of living organisms and their interactions with abiotic (non-living) components of the environment.

Biosphere

The sum of all ecosystems on Earth; includes land, water, and atmosphere.

Global Circulation Patterns

Movement of air initiated by solar heating, resulting in winds and precipitation patterns.

Coriolis Effect

The deflection of moving air/water due to Earth’s rotation—counterclockwise in the Northern Hemisphere and clockwise in the Southern.

Rain Shadow Effect

Occurs when moist air rises over a mountain and loses its moisture; the leeward side becomes dry.

Monsoons

Seasonal wind shifts that bring large amounts of rain, especially in South and Southeast Asia.

Microclimates

Small localized climate zones that differ from the surrounding area (e.g., shade under a tree).

Biomes

Broad ecological communities defined by climate and dominant vegetation, such as desert, tundra, tropical rainforest, etc.

Aquatic Biomes

Include coral reefs, estuaries, intertidal zones, hydrothermal vents, lakes, and rivers.

Thermal Stratification

Layering in water due to temperature differences; the thermocline separates warmer surface water from colder bottom layers.

Eutrophication

Nutrient buildup in aquatic ecosystems leading to excessive algae growth, oxygen depletion, and dead zones.

Overfishing

Harvesting fish at rates faster than they can reproduce; may lead to ecosystem collapse.

Climate Change

Long-term changes in temperature and weather patterns; can have both harmful and some beneficial ecological effects.

El Niño and La Niña

Unpredictable ocean temperature shifts in the Pacific—El Niño warms oceans; La Niña cools them.

Ozone Layer

Stratospheric layer that absorbs UV radiation; was damaged by chlorofluorocarbons (CFCs).

Population Range

Geographic area over which a population is distributed.

Population Density

Number of individuals per unit area.

Dispersion Patterns

Spatial distribution of individuals (clumped, uniform, random).

Population Demography

Study of how populations change in size and structure over time.

Life History

The complete life cycle of an organism, including age at reproduction and lifespan.

Carrying Capacity (K)

Maximum number of individuals an environment can support sustainably.

Density-Dependent Effects

Biotic factors (e.g., predation, competition) that increase in intensity as population grows.

Density-Independent Effects

Abiotic events (e.g., weather) that affect population regardless of size.

Biotic Potential (r)

The maximum rate at which a population can grow with unlimited resources.

Exponential Growth

Population increase under ideal, unlimited conditions (J-shaped curve).

Logistic Growth

Growth slows as population approaches carrying capacity (S-shaped curve).

Per Capita Growth Rate

Birth rate minus death rate per individual.

r-selected Species

Reproduce quickly, high mortality, thrive in unstable environments.

K-selected Species

Reproduce slowly, high survival, thrive near carrying capacity.

Survivorship Curves

Graphs showing survival rates across life spans (Types I, II, III).

Life Tables

Charts summarizing birth and death rates across age groups.

Cohort

Group of individuals born at the same time.

Expected Age Classes

Age structure reflecting population growth trends.

Iteroparity

Multiple reproductive events over lifetime.

Semelparity

Single reproductive event (e.g., agave).

Community

All interacting species in a particular location.

Ecosystem

Community plus abiotic environment.

Predator-Prey Interaction

Drives natural selection in both predator and prey.

Resource Partitioning

Sympatric species use different resources or habitats to avoid competition.

Allopatric Species

Occupy separate geographic areas; no direct competition.

Intraspecific Competition

Between members of the same species.

Interspecific Competition

Between different species.

Parasitism

One species benefits, the other is harmed.

Parasitoid

Insects that lay eggs on or in hosts, eventually killing them.

Commensalism

One species benefits, the other is unaffected.

Mutualism

Both species benefit from the interaction.

Succession

Predictable changes in community structure over time.

Primary Succession

Occurs on lifeless surfaces (e.g., lava flows).

Secondary Succession

Follows disturbance in existing community (e.g., fire, farming).

Keystone Species

Disproportionately influence community structure.

Plant Defenses

Physical or chemical adaptations to deter herbivores.

Secondary Compounds

Plant chemicals that deter predators or attract specialized herbivores.

Cryptic Coloration

Camouflage used to avoid detection by predators.

Warning Coloration

Bright colors signaling toxicity or distastefulness.

Müllerian Mimicry

Multiple harmful species resemble each other.

Batesian Mimicry

Harmless species mimics harmful one.

Biogeochemical Cycles

The movement of chemical elements (like carbon, nitrogen, phosphorus) through biotic (living) and abiotic (non-living) parts of the environment.

Carbon Cycle

Movement of carbon among the atmosphere, oceans, living organisms, and fossil fuels. Major reservoirs include atmosphere, oceans, fossil fuels, and biomass.

Water Cycle

Circulation of water through evaporation, condensation, precipitation, runoff, and infiltration. Includes groundwater storage like aquifers.

Nitrogen Cycle

The cycle of nitrogen through the atmosphere, soil, and organisms. Includes processes like nitrogen fixation, nitrification, and denitrification.

Phosphorus Cycle

Movement of phosphorus through soil, water, and organisms. Essential for nucleic acids and membranes. No atmospheric phase.

Limiting Nutrients

Nutrients in shortest supply that limit primary productivity (e.g., nitrogen, phosphorus, iron in oceans).

Dead Zones

Oxygen-depleted areas in aquatic systems caused by excessive nutrient runoff and algal blooms. Common in coastal areas like the Gulf of Mexico.

Greenhouse Effect

Natural process where greenhouse gases (like CO₂) trap heat in the atmosphere, warming the Earth.

Permafrost

Permanently frozen ground that stores trapped methane; thawing can accelerate climate change.

Energy Flow

Movement of energy through trophic levels in an ecosystem—from producers to consumers to decomposers.

Ecological Pyramids

Graphical representations of energy, biomass, or number of organisms at each trophic level.

Ecosystem Stability: Resistance

Ability to stay stable during a disturbance.

Ecosystem Stability: Resilience

Ability to recover after a disturbance.

Biomagnification

Process where toxins increase in concentration as they move up trophic levels, affecting top predators the most.

Top-Down Effects

Control of ecosystem structure by predators; removing them can lead to overpopulation of prey.

Bottom-Up Effects

Changes at the producer level (e.g., nutrient availability) affect the rest of the food web.

Food Chain

Linear sequence showing one path of energy flow through organisms.

Food Web

Complex, interconnected network of multiple food chains showing real- world feeding relationships.

Biodiversity Crisis

The rapid, human-driven decline in Earth’s species richness and ecosystem health.

Mass Extinction

A widespread, global event leading to a sharp loss of species. Earth has experienced five, and we may be entering a sixth.

Habitat Loss

The destruction or fragmentation of natural habitats (e.g., deforestation); major cause of species decline (e.g., Florida panther).

Overharvesting

Excessive hunting, fishing, or collecting of species, often leading to collapse (e.g., overfished coral reef species).

DNA Barcoding

Use of genetic identification to catalog species and monitor illegal wildlife trade.

Biodiversity Hotspots

Regions with exceptionally high species richness and endemism, often under threat.

Preserves

Protected areas aimed at conserving biodiversity. Effectiveness depends on size, location, and human pressures.

Restoration

Active efforts to return degraded ecosystems to their natural state.

Captive Breeding

Breeding species in captivity with the goal of reintroducing them into the wild.

Biodiversity

Variety of life at genetic, species, and ecosystem levels. Supports evolutionary potential and ecological balance.

Genetic Diversity

Variation in genes within a population; essential for adaptability and survival.

Chemical Diversity

Variety of biochemical compounds; reflects genetic diversity and potential for new medicines, etc.

Endemic Species

Species found only in a specific, limited area (e.g., island or microhabitat).

Exotic Species

Non-native organisms introduced into new ecosystems, sometimes invasive.

Invasive Species

Exotic species that outcompete or prey on native species, disrupting ecosystems.

Ecosystem Services

Benefits humans obtain from ecosystems (e.g., pollination, water purification, climate regulation).

Keystone Species

Species that have a disproportionately large impact on their ecosystem relative to their abundance.

Agricultural Diversity

Variety of crops and livestock critical to food security and resilience against disease or climate change.