unit 2 olivia flashcards

Genetic Diversity

Genetic Diversity

The total number of genetic characteristics present within the genetic makeup of a species.

Importance of Genetic Diversity

It enhances a population's ability to adapt to changing environments, improves resilience against diseases, and lowers the risk of extinction.

Species Diversity

The variety of different species within a particular habitat or ecosystem.

Measures of Species Level Biodiversity

Common measures include species richness (the number of species) and species evenness (how evenly individuals are distributed across species).

Importance of Species Diversity

It contributes to ecosystem stability, productivity, and resilience, allowing ecosystems to withstand environmental changes.

Habitat Diversity

The variety of different habitats present in a given area or ecosystem.

Importance of Habitat Diversity

It supports a wider range of species, promotes ecosystem resilience, and enhances overall ecological health.

Relationship Between Habitat Diversity and Species Diversity

Higher habitat diversity typically leads to greater species diversity, as more niches and resources are available to support various organisms.

Ecosystem Functioning and Habitat Diversity

Diverse habitats contribute to processes such as nutrient cycling, water filtration, and energy flow, which are essential for ecosystem health.

Effects of Habitat Loss on Diversity

Habitat loss reduces the number of available niches, leading to decreased species richness and loss of genetic diversity as populations decline.

Why Habitat Loss Affects Diversity

Habitat loss disrupts ecosystems, limiting resources essential for survival, reproduction, and overall population stability, which ultimately lowers diversity.

Ecosystem Services

The benefits that humans derive from ecosystems, which are categorized into four main types: provisional, cultural, regulating, and supporting.

Provisional Ecosystem Services

These are products obtained from ecosystems, such as food, fresh water, timber, and fiber. Example: Harvesting fish from oceans.

Cultural Ecosystem Services

Non-material benefits obtained from ecosystems, including recreational, aesthetic, and spiritual benefits. Example: Ecotourism or hiking in natural parks.

Regulating Ecosystem Services

The benefits obtained from the regulation of ecosystem processes, like climate regulation, water purification, and pollination. Example: Wetlands filtering pollutants from water.

Supporting Ecosystem Services

These services are necessary for the production of all other ecosystem services, including nutrient cycling and soil formation. Example: Soil microbes decomposing

Anthropogenic Activities

Human actions that impact the environment, including urbanization, agriculture, pollution, and deforestation.

Impact of Urbanization on Ecosystem Services

Urbanization can lead to habitat loss and increased pollution, which disrupts regulating services like air and water purification. Example: Concrete surfaces reduce water filtration.

Impact of Agriculture on Ecosystem Services

Intensive agriculture can degrade soil quality and reduce biodiversity, affecting supporting services such as nutrient cycling. Example: Monoculture practices decrease soil fertility.

Impact of Pollution on Ecosystem Services

Pollution can contaminate air, soil, and water, degrading cultural and regulating services; for instance, pesticide runoff impacts aquatic ecosystems.

Impact of Deforestation on Ecosystem Services

Deforestation reduces carbon sequestration and habitat diversity, affecting global climate regulation and species richness. Example: Logging decreases forest cover and biodiversity.

Economic Impacts of Ecosystem Service Degradation

Ecosystem service degradation can lead to increased costs for water treatment, health expenses due to pollution, and loss of revenue from natural resources.

Ecological Impacts of Ecosystem Service Degradation

Disruption of ecosystem services can lead to loss of biodiversity, increased vulnerability to natural disasters, and reduced ecosystem resilience.

Example of Ecosystem Service Loss from Anthropogenic Activities

Coral bleaching due to ocean temperature rise from climate change affects marine biodiversity and fish populations, impacting food provision services.

Mitigation Strategies for Ecosystem Service Recovery

Strategies include reforestation, sustainable agriculture, and pollution control measures to help restore and enhance ecosystem services.

Island Biogeography

The study of the ecological relationships and distribution of species on islands and the factors affecting the number of species present.

Effects of Island Size on Species Richness

Larger islands typically support more species due to greater habitat diversity and available resources.

Effects of Distance from Mainland on Species Diversity

Islands that are closer to the mainland tend to have higher species richness due to easier dispersal of organisms and colonization.

Equilibrium Theory of Island Biogeography

The theory that proposes a balance between immigration and extinction rates, determining the number of species on an island.

Species-Area Relationship

The principle that states as the area of an island increases, the number of species it can support generally increases, following a logarithmic pattern.

Isolation and Species Diversity

Heavily isolated islands may have fewer species because they are harder to reach, resulting in lower colonization rates.

Habitat Availability on Islands

The number of ecological niches available for species, which influences overall species richness on islands.

Edge Effects on Island Biodiversity

Habitat edges can create microclimates and increase resource availability, affecting species

Effective Colonizers on Islands

Species that are typically effective at colonizing islands include r-selected species, such as certain birds, insects, and plants, which reproduce quickly and in large numbers.

Role of Adaptive Radiation

Adaptive radiation occurs when species diversify to fill different ecological niches on the island, leading to a variety of forms that are better suited to their specific environments.

Evolutionary Changes in Isolated Species

Species on islands may undergo evolutionary changes that enhance survival, such as changes in size, coloration, or behavior to adapt to unique island conditions.

Founder Effect

The founder effect describes the reduced genetic diversity that occurs when a small group of individuals establishes a new population on an island.

Ecological Release

Ecological release happens when species face reduced competition and predation on islands, allowing them to expand their niche and increase in abundance.

Endemic Species

Endemic species are those that are unique to a specific island, having evolved in isolation from other populations due to geographic and ecological factors.

Evolution of Island Flora and Fauna

Island flora and fauna often evolve unique traits and behaviors due to isolation, leading to distinct species that may

Terrestrial Mammals

Large terrestrial mammals, such as elephants and bears, are generally absent from islands due to their size and specialized habitat requirements, making it challenging for them to traverse water.

Large Carnivores

Large carnivores like lions or tigers are typically not found on islands, as they require expansive territories and abundant prey that are often not present in isolated ecosystems.

Highly Specialized Species

Organisms that have highly specialized diets or habitat requirements are less likely to thrive on islands, where resources may be limited and not all niches are filled.

Species with Low Dispersal Ability

Organisms that lack effective means of dispersal, such as flightless birds or plants with heavy seeds, may find it difficult to reach and colonize island environments.

Invasive Species

While not native, invasive species can often be found on islands; however, native islands are expected to contain fewer species that have adapted to their unique environments.

Large Herbivores

Large herbivores, such as deer or large primates, may also be less common on islands due to limited food resources and hunting pressures

Ecological Tolerance

The range of environmental conditions (such as temperature, salinity, and pH) within which a species can survive, grow, and reproduce.

Ecological Tolerance Limits

If an organism falls outside its ecological tolerance limits, it may experience stress, reduced fitness, and potentially death. This usually requires changes in environmental conditions, such as temperature or salinity, that exceed the organism's ability to adapt.

Natural Disruptions

Natural disruptions are events that significantly alter the structure or function of an ecosystem, which can be short-term (like storms) or long-term (like volcanic eruptions).

Short-Term Natural Disruptions

Short-term disruptions, such as hurricanes or floods, can cause immediate destruction, displacing species and altering habitat but may allow for quick recovery and regeneration.

Long-Term Natural Disruptions

Long-term disruptions, such as climate change or geological disturbances, can permanently alter ecosystems, leading to shifts in species composition and ecosystem functions.

Impact of Natural Disruptions on Biodiversity

Natural disruptions can increase biodiversity by creating new habitats or niches, but can also decrease it by causing extinctions or reducing population sizes.

Ecosystem Resilience and Natural Disruptions

Ecosystem resilience is the capacity of an ecosystem to recover from disturbances; resilient ecosystems can quickly bounce back from both short and long-term disruptions.

Role of Disturbances in Ecosystem Dynamics

Disturbances can drive ecosystem dynamics by promoting species diversity, nutrient cycling, and habitat complexity, ultimately shaping the structure and function of ecosystems.

Example of Short-Term Disruption Impact

A short-term drought can lead to immediate water scarcity affecting plant health, but rain shortly after can help restore the ecosystem.

Example of Long-Term Disruption Impact

Rising sea levels due to climate change can permanently inundate coastal wetlands, altering habitats for numerous species.

Scale of Natural Disruptions

Natural disruptions can vary in scale from localized events, like a fallen tree, to widespread phenomena, such as wildfires or hurricanes affecting large regions.

Timing of Natural Disruptions

Natural disruptions can occur as acute (sudden events) or chronic (long-term changes), impacting ecosystems differently depending on the timing and frequency.

Most Damaging Natural Disruptions

Major hurricanes, prolonged droughts, and volcanic eruptions are often the most damaging due to their intensity, duration, and capacity to change habitats permanently.

Localized Natural Disruptions

Localized events, like landslides or small fires, generally have lesser impacts on a broader ecosystem compared to large-scale disruptions.

Chronic Natural Disruptions

Chronic disruptions, like climate change, can cause ongoing stress to ecosystems, leading to gradual loss of biodiversity and habitat degradation.

Resilience Factors in Ecosystems

Ecosystem resilience is influenced by biodiversity, habitat complexity, and the ability to recover from both short-term and long-term

Role of Natural Disruptions in Adaptation

Natural disruptions can create new selective pressures that favor certain traits, leading to adaptations among species that enhance survival in changed environments.

Examples of Adaptations to Natural Disruptions

1. Fire Adaptation: Some plants, like pine trees, have evolved to require fire for seed germination. 2. Drought Resistance: Certain desert plants develop deep root systems to access underground water. 3. Flood Tolerance

Long-Term Climate Change Effects on Habitat Loss

Long-term climate change can lead to altered weather patterns, decreasing habitats for species that are unable to adapt or migrate.

Sea-Level Rise and Habitat Loss

Rising sea levels due to climate change can inundate coastal habitats, leading to the loss of wetlands, estuaries, and critical nesting grounds for various species.

Species Migration Due to Climate Change

As climate changes, species may migrate to cooler areas, altering existing ecosystems and potentially leading to habitat loss for those that cannot move.

Impact of Ocean Temperature Rise on Marine Habitats

Increased ocean temperatures can lead to coral bleaching, drastically reducing biodiversity in marine ecosystems and affecting associated species.

Saltwater Intrusion from Sea-Level Rise

Rising sea levels can cause saltwater to intrude into freshwater habitats, disrupting ecosystems and affecting species that rely on freshwater resources.

Effects of Extreme Weather Events on Habitat Stability

Increased frequency of extreme weather events, such as hurricanes and droughts, can lead to habitat degradation and increased vulnerability of ecosystems.

Buffer Capacity of Coastal Habitats

Healthy coastal habitats, like mangroves and wetlands, can provide buffers against sea-level rise, but their loss exacerbates habitat vulnerability.

Adaptation

A trait that enhances an organism's ability to survive and reproduce in its environment.

Types of Adaptations

Adaptations can be structural (physical features), behavioral (actions), or physiological (internal functions).

Role of Natural Selection in Adaptation

Natural selection favors organisms with adaptations that provide advantages in survival and reproduction, leading to gradual change in the species over generations.

Environmental Pressure

Factors in the environment, such as predators, climate, and resources, that influence the survival and reproduction of organisms, prompting adaptations.

Example of Structural Adaptation

The long neck of the giraffe allows it to reach high leaves, providing access to food that shorter animals cannot reach.

Example of Behavioral Adaptation

Migration patterns of birds that adjust based on seasonal changes to find food and suitable breeding grounds.

Example of Physiological Adaptation

Some desert plants have developed the ability to store water in their tissues, allowing them to survive in arid conditions.

Convergent Evolution

The process whereby unrelated organisms independently evolve similar traits as a result of adapting to similar environments.

Divergent Evolution

The process where two or more related species become more dissimilar, often due to adaptation to different environments.

Fitness in Evolutionary Terms

The ability of an organism to survive and reproduce in a specific environment, contributing to the genetic makeup of future generations.

Evolution via Natural Selection

A process where individuals with favorable traits are more likely to survive and reproduce, leading to the gradual evolution of species. Example: Peppered moths changing color to blend with their environment.

Artificial Selection

The intentional breeding of organisms to produce desired traits. Example: Dog breeding for specific physical characteristics or behaviors.

Founder Effect

A phenomenon where a small group establishes a new population, leading to reduced genetic diversity. Example: A small group of colonizers on an island gives rise to a new, genetically distinct population.

Genetic Drift

Random changes in allele frequencies within a population, often having a significant effect in small populations. Example: A natural disaster randomly eliminates allele variants, altering the gene pool.

Gene Flow

The transfer of genetic material between populations through migration, which can introduce new alleles and increase genetic diversity. Example: Pollen from one plant population fertilizing flowers in another region.

Random Mutation

Spontaneous changes in DNA sequences that can lead to new traits within a population. Example: A mutation in a bacterial population that grants antibiotic resistance.

Genetic Bottleneck

An event that drastically reduces population size and genetic diversity, leading to a narrow gene pool. Example: The Northern elephant seal, which underwent

Primary Ecological Succession

The process of community development that occurs in lifeless areas where soil has not yet formed, such as after a volcanic eruption or glacier retreat.

Stages of Primary Ecological Succession

Begins with pioneer species (like lichens and mosses) colonizing barren land, followed by grasses, shrubs, and eventually trees as soil develops.

Secondary Ecological Succession

The process of recovery and change in a community following a disturbance that does not destroy the soil, such as after a forest fire or flood.

Differences Between Primary and Secondary Succession

Primary succession starts in bare rock or lifeless areas, while secondary succession occurs in previously inhabited areas where soil and seed banks remain.

Pioneer Species

Species, such as lichens and mosses, that first colonize previously uninhabited or disturbed environments, initiating the process of ecological succession.

Climax Community

A stable and mature ecological community that has reached the final stage of succession, characterized by a balanced diversity of species and interactions.

Impact of Disturbances on Succession

Natural disturbances, like fires or storms, can reset successional stages, leading to new opportunities for species establishment and community dynamics.

Role of Soil Formation in Succession

Soil development is crucial for primary succession, as it creates conditions that allow for the growth of more complex plant communities.

Effects of Primary Succession on Ecosystems

Primary succession typically starts with low species composition and biodiversity, gradually increasing as pioneer species modify the environment to support more complex communities.

Species Composition in Primary Succession

Pioneer species first establish, followed by intermediate species, leading to a diverse climax community with various interactions.

Biomass in Primary Succession

Biomass is initially low during primary succession but increases over time as plant and animal communities develop and diversify.

Net Primary Production (NPP) in Primary Succession

NPP begins low but increases as ecosystem complexity grows, reflecting greater plant biomass and energy capture over time.