Podcast
Questions and Answers
What are the three abilities mentioned that contribute to a species' success in an ecosystem?
What are the three abilities mentioned that contribute to a species' success in an ecosystem?
Ability to move long distances, high productivity, able to withstand unsuitable conditions between patches.
Species diversity decreases with island size.
Species diversity decreases with island size.
False
What is an ecological niche?
What is an ecological niche?
The relational position of a species or population in an ecosystem, including its role in resource distribution and interactions with competitors.
What are the two aspects to consider regarding ecological integrity?
What are the two aspects to consider regarding ecological integrity?
Signup and view all the answers
What is the difference between top-down and bottom-up regulation?
What is the difference between top-down and bottom-up regulation?
Signup and view all the answers
What is a trophic cascade?
What is a trophic cascade?
Signup and view all the answers
What is natural selection?
What is natural selection?
Signup and view all the answers
What drives adaptive radiation?
What drives adaptive radiation?
Signup and view all the answers
Natural selection acts on genetic traits and not on observable characteristics.
Natural selection acts on genetic traits and not on observable characteristics.
Signup and view all the answers
The _____ of energy in ecosystems is ultimately lost as heat.
The _____ of energy in ecosystems is ultimately lost as heat.
Signup and view all the answers
What does the theory of punctuated equilibrium propose?
What does the theory of punctuated equilibrium propose?
Signup and view all the answers
What is convergent evolution?
What is convergent evolution?
Signup and view all the answers
What is cladogenesis?
What is cladogenesis?
Signup and view all the answers
What is the Intermediate Disturbance Hypothesis (IDH)?
What is the Intermediate Disturbance Hypothesis (IDH)?
Signup and view all the answers
What does the theory of punctuated equilibrium propose?
What does the theory of punctuated equilibrium propose?
Signup and view all the answers
What is local adaptation?
What is local adaptation?
Signup and view all the answers
What does a minimum dynamic area (MDA) refer to?
What does a minimum dynamic area (MDA) refer to?
Signup and view all the answers
How is adaptive capacity defined?
How is adaptive capacity defined?
Signup and view all the answers
What was the primary focus of the SLOSS (Single Large or Several Small) debate?
What was the primary focus of the SLOSS (Single Large or Several Small) debate?
Signup and view all the answers
What is genetic drift?
What is genetic drift?
Signup and view all the answers
As one moves from the core to the periphery of a species' range, populations always occupy more favorable habitats.
As one moves from the core to the periphery of a species' range, populations always occupy more favorable habitats.
Signup and view all the answers
What is inbreeding depression?
What is inbreeding depression?
Signup and view all the answers
What is the difference between exponential and logistic population growth?
What is the difference between exponential and logistic population growth?
Signup and view all the answers
What are the two types of extinction vortex factors?
What are the two types of extinction vortex factors?
Signup and view all the answers
What defines a metapopulation?
What defines a metapopulation?
Signup and view all the answers
What does the source-sink model imply?
What does the source-sink model imply?
Signup and view all the answers
What does effective population size refer to?
What does effective population size refer to?
Signup and view all the answers
What are the two types of ecological succession described?
What are the two types of ecological succession described?
Signup and view all the answers
What are prominent anthropogenic impacts on ecosystems?
What are prominent anthropogenic impacts on ecosystems?
Signup and view all the answers
What is adaptive (resource) management?
What is adaptive (resource) management?
Signup and view all the answers
Which focal species concept refers to species whose conservation benefits many other species?
Which focal species concept refers to species whose conservation benefits many other species?
Signup and view all the answers
What is the role of zoos in conservation?
What is the role of zoos in conservation?
Signup and view all the answers
How can habitat fragmentation sometimes be beneficial?
How can habitat fragmentation sometimes be beneficial?
Signup and view all the answers
What is island biogeography?
What is island biogeography?
Signup and view all the answers
What is the main role of zoos?
What is the main role of zoos?
Signup and view all the answers
What are the four main ways zoos contribute to conservation?
What are the four main ways zoos contribute to conservation?
Signup and view all the answers
What is the purpose of captive breeding programs?
What is the purpose of captive breeding programs?
Signup and view all the answers
The genetic diversity of species is not important for conservation.
The genetic diversity of species is not important for conservation.
Signup and view all the answers
What can happen if captive bred animals are released without sufficient habitat?
What can happen if captive bred animals are released without sufficient habitat?
Signup and view all the answers
What is one area of research conducted by zoos?
What is one area of research conducted by zoos?
Signup and view all the answers
What complicates understanding urban ecosystems?
What complicates understanding urban ecosystems?
Signup and view all the answers
What is one key characteristic of urban environments?
What is one key characteristic of urban environments?
Signup and view all the answers
What are some negative impacts of urban heat islands?
What are some negative impacts of urban heat islands?
Signup and view all the answers
What do the research trends indicate about species diversity in urban areas?
What do the research trends indicate about species diversity in urban areas?
Signup and view all the answers
Which species are mentioned as showing trends in urban areas?
Which species are mentioned as showing trends in urban areas?
Signup and view all the answers
Study Notes
Intermediate Disturbance Hypothesis (IDH)
- Proposes that local species diversity peaks at intermediate levels of ecological disturbance.
- Low disturbance favors competitive K-selected species, reducing diversity.
- High disturbance levels (e.g., forest fires) threaten all species, also decreasing diversity.
- Intermediate disturbance allows coexistence of K-selected and r-selected species due to differing adaptability to disturbance.
- K-selected species invest resources in competition and growth, while r-selected species rapidly colonize disturbed areas.
Minimum Dynamic Area (MDA)
- Represents the smallest area of suitable habitat needed for a viable, long-term population.
- Essential for assessing project impacts and managing ecological communities without human intervention.
- Relates to natural disturbance regimes necessary for species survival.
Single Large or Several Small (SLOSS) Debate
- Discusses whether one large reserve or multiple smaller reserves better conserve biodiversity.
- Larger reserves are thought to support more species due to greater habitat size.
- Smaller reserves may contain unique species, potentially surpassing larger reserves in species richness.
- Challenges to the theory include critiques on nested species composition and fragmentation's role in biodiversity loss.
- Influential studies have examined species distribution in relation to reserve size and habitat fragmentation.
Conservation of Species at the Core versus Periphery
- Core populations are more robust, located in favorable habitats, while peripheral populations are often fragmented and less dense.
- Periphery populations have increased extinction risk due to lower immigration rates.
- Range contraction typically moves species towards their core as they become endangered, but many species persist in peripheral zones.
Exponential and Logistic Population Growth
- Exponential models describe potential rapid population increases, especially when resources are temporarily unrestricted.
- As populations grow, density-dependent factors (e.g., food, disease, predation) slow growth rates, creating a logistic growth curve.
- Logistic growth showcases how populations stabilize at carrying capacity (K), defined as the maximum sustainable population size.
Metapopulation Dynamics
- Composed of interconnected sub-populations, allowing for genetic exchange and local extirpation/recolonization.
- Balances population dynamics through immigration from sources to sinks, supporting persistent populations.
Source-Sink Population Dynamics
- Source patches provide high-quality habitats fostering population growth, while sink patches are low-quality habitats that may not sustain populations alone.
- Organisms ideally prefer high-quality sources but can be drawn to sinks due to ecological traps.
- Understanding these dynamics is crucial for informed conservation strategies.
Succession and Community Concepts (Clements vs. Gleason)
- Clements viewed ecological succession as predictable and deterministic, converging on stable climax communities.
- Gleason argued for a more individualistic perspective, where species distributions responded to environmental factors and chance.
- Primary succession occurs in barren environments lacking soil, while secondary succession happens in areas that previously supported vegetation.
Focal Species Concepts
- Umbrella species protect broader ecosystems when conserved.
- Indicator species reflect the health of other species or environmental conditions.
- Keystone species play vital roles in ecosystem dynamics, disproportionately affecting their environment.
- Flagship species generate awareness for conservation efforts.
Habitat Fragmentation
- Not always detrimental; can prevent disease spread and maintain genetic diversity.
- Edges can benefit some species but may pose risks for "interior" species sensitive to habitat changes.
- The concept of depth-of-edge influence relates to the extent to which edges affect the inner habitat.
Island Biogeography
- Species diversity correlates positively with island size and isolation, affecting connectivity and colonization potential.
- Larger islands generally support more species, with initial rapid increases in diversity plateauing at larger sizes.
Ecological Niche
- Describes a species' role in an ecosystem, including resource utilization and interactions with competitors and predators.
- Species can influence their environment and community structure through their ecological niches.
Ecological Resiliency and Integrity
- Defined by the abundance and diversity of organisms and the interrelated ecological processes supporting them.
- Healthy ecosystems show high biodiversity and functional integrity through minimal disturbance and balanced nutrient cycling.
- Ecological integrity is considered essential for maintaining biological communities and their habitat characteristics.### Ecological Integrity
- Ecological integrity applies to various scales, including stands, watersheds, and landscapes.
- Forests unaffected by human activities possess higher ecological integrity compared to those with extensive clear-cutting.
- Sustainable timber extraction methods aim to mimic natural disturbances, helping forest ecosystems maintain biodiversity.
- Managed forests that emulate natural systems yield better long-term timber production.
Top-Down vs. Bottom-Up Regulation
- Environmental regulations can be classified into top-down and bottom-up approaches, both aiming for sustainability.
- Ecosystem productivity is influenced by resource availability, including light, water, and nutrients.
- The nitrogen to phosphorus ratio in algae influences which nutrient limits growth; a ratio of about 16:1 is key.
- Essential resources are critical for growth, while substitutable resources can be interchanged.
- Bottom-up controls stem from resource availability affecting energy flow to higher trophic levels.
- Top-down controls relate to predator abundance influencing prey populations; this dynamic can affect conservation strategies.
- Keystone species significantly impact ecosystem health; their removal causes drastic changes, exemplified by wolves in Yellowstone.
Food Webs and Nutrient Flows
- Food webs illustrate the movement of energy and nutrients in ecosystems.
- Energy flows from the sun, is utilized by organisms, and ultimately lost as heat; it does not recycle.
- Inorganic nutrients, such as nitrogen, phosphorus, and iron, circulate within ecosystems and are recycled.
- Decomposers play a crucial role in returning nutrients to the soil after energy extraction has occurred.
- A food chain showcases the direct path of energy transfer from producers through various consumers.
Functional vs. Numerical Response
- Predators exhibit variable harvesting rates influenced by prey density, characterized by functional and numerical responses.
- Three classes of functional responses range from linear increases to sigmoidal patterns as prey density changes.
- Numerical responses involve the relationship between predator and prey populations, potentially including direct increases or declines.
Trophic Cascades
- Trophic cascades occur when predator suppression of prey affects the entire food chain.
- Removal of top predators can lead to significant changes within ecosystems, with cascading effects throughout lower trophic levels.
Natural Selection
- Natural selection is a key evolutionary process that modifies trait frequency based on reproductive success.
- Variability in traits stems from random mutations and environmental interactions.
- Selection acts on phenotypes, influencing allele frequencies and may lead to specialization or new species.
Adaptive Radiation
- Adaptive radiation occurs when a founder species diversifies into many due to abundant ecological niches, as seen in groups like Darwin's finches.
Convergent Evolution
- Convergent evolution involves different species evolving similar traits independently due to similar environmental pressures.
Punctuated Equilibrium Theory
- Punctuated equilibrium suggests species remain stable for long periods with sporadic significant evolutionary changes during rapid events.
Local Adaptation
- Local adaptation describes genetic change in response to localized selection pressures, influencing traits in specific environments.
Adaptive Capacity
- Adaptive capacity is determined by genetic diversity, biodiversity of ecosystems, and variations in environmental conditions impacting species resilience.
Genetic Drift
- Genetic drift entails random changes in allele frequencies within populations, affecting genetic variation and potentially eliminating alleles.
Inbreeding Depression
- Inbreeding depression decreases population fitness from mating between closely related individuals, often resulting from population bottlenecks.
Extinction Vortex
- Extinction vortex refers to a process where reduced population size leads to further decline due to genetic and demographic factors.### Genetic Causes of Population Extinction
- Extinction Vortex: Small populations face an increased risk of extinction due to the interplay of demographic and genetic factors.
- Natural Selection: Promotes beneficial traits while eliminating genetic weaknesses. However, genetic drift can spread harmful mutations.
- Genetic Diversity: A diverse gene pool boosts survival chances during environmental changes. Loss of diversity correlates with higher extinction risks.
- Population Bottlenecks: Severe reductions in population size lead to decreased genetic diversity and increased inbreeding risks.
- Founder Effect: A dramatic example of population bottlenecks, leading to rapid speciation but potentially diminished gene pools.
Demographic Factors
- Stochastic Variation: Small populations experience significant fluctuations in reproductive and mortality rates, increasing extinction probability.
- Sensitivity to Genetic Drift: Smaller populations are more susceptible to changes in allele frequencies due to chance, affecting gene diversity and demographic stability.
- Homozygosity: High levels of homozygosity can lead to increased risks from deleterious alleles, which are more damaging in a homozygous state.
- Polymorphism Importance: Genetic variation within populations, especially at immune response loci, is crucial for adaptability.
Genetic Variation Mechanisms
- Genetic Drift: In small populations, chance events can lead to significant changes in allele frequencies, sometimes resulting in harmful fixation of alleles.
- Inbreeding: Increased likelihood of mating among related individuals leads to higher homozygosity and can introduce inbreeding depression.
Consequences of Loss of Genetic Variation
- Inbreeding Depression: Results from decreased genetic variation, affecting population health and adaptability. More profound in populations that were already small.
- Muller's Ratchet: A phenomenon where the accumulation of deleterious alleles in small populations can result in mutational meltdown.
Effective Population Size
- Definition: Represents the breeding population size influenced by reproductive structure, family size, and variations in offspring.
- Significance: The effective population size (N(e)) is vital for understanding genetic drift impacts and variability within populations.
Anthropogenic Impacts on Ecosystems
- Resource Demand: The growing human population increases the strain on Earth's resources.
- Fossil Fuel Emissions: Contribute to global warming and acidification, affecting biosphere health.
- Freshwater Pollution: Threatens both habitat integrity and public health through biomagnification effects.
- Biodiversity Threats: Habitat loss and invasive species driven by human activities jeopardize species survival.
Adaptive Management
- Decision Process: Emphasizes flexibility in management as outcomes from actions are observed and understood over time.
- Management as Experimentation: Policies are seen as hypotheses to refine through research and ecological response monitoring.
- Focus on Resilience: Aims to maintain ecological resilience, ensuring systems can adapt to inevitable stresses while preventing irreversible damage.
- Role of Stakeholders: Effective adaptive management requires inclusive processes, integrating knowledge from various stakeholders.
Role of Zoos in Conservation
- Historical Context: Zoos have existed for millennia and have transitioned from mere display to active conservation roles.
- Captive Breeding Success: Zoos participate in saving endangered species through breeding programs, ensuring genetic diversity.
- Public Education: Zoos help raise awareness and understanding of conservation issues through informative displays and school programs.
- Research Contributions: Conduct important research for both captive and wild species, enhancing conservation efforts and animal care.
Urban Ecosystems and Urbanization
- Definition: Urban ecosystems are characterized by high population density and significant built infrastructure impacts.
- Urban Heat Island Effect: Caused by altered land surfaces, leading to increased local temperatures and related environmental impacts.
- Consequences of Urbanization: Heightened energy consumption, increased air pollution, and impaired water quality from stormwater runoff are significant challenges in urban planning.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Prepare for your wildlife ecology exam with these flashcards focusing on key concepts like the Intermediate Disturbance Hypothesis. This review will help you understand how species diversity is influenced by varying levels of ecological disturbance. Perfect for students looking to solidify their knowledge in this important ecological theory.
