APES Unit 2

Biodiversity

The variability of life on Earth/in an ecosystem

Genetic, species, and habitat diversity

Biodiversity includes…

Bottleneck effect

A biological phenomenon where a population's size is dramatically reduced, leading to a loss of genetic diversity and a reduction in the variety of gene combinations within the surviving gene pool

Environmental stressors

The larger amount of genetic diversity in a population, the better it can respond to…

Recover from disruptions

Ecosystems with larger numbers are more likely to…

Generalist species

An organism with a broad ecological niche, meaning it can survive and thrive in a wide variety of environmental conditions and utilize a diverse range of food sources

Specialist

An organism with a narrow ecological niche, meaning it requires specific food sources, habitats, and a limited range of environmental conditions to survive and reproduce

Habitat loss

Disruption that leads to a loss of specialist species followed by a loss of generalist species, and a reduced number of species that have large territorial requirements

Species Richness

The number of different species found in an ecosystem

Ecosystem services

Provisioning, regulating, cultural, and supporting

Provisioning

Ecosystem service- The material products that people get from ecosystems

Examples of provisioning services

Natural products like water, food, timber, other products such as as coal, natural gas, petroleum, and antibiotics used to treat infections derived from fungi and bacteria

Regulating

Ecosystem service - ecosystem processes that control natural phenomena

Examples of regulating services

Biodiversity helps maintain air quality, regulate water runoff and flooding, control erosion, purify water, and decompose waste. Pollinators help plant fertilization for seed development and fruit production

Cultural

Ecosystem service - the non-material benefits that people obtain from ecosystems. A vital part of the history, heritage, and diversity of peoples, cultures, and societies around the world

Examples of cultural services

Tourism, recreation, bird watching, enjoying beauty, and other activities that can provide joy, relaxation, and a connection to biodiversity. Getting inspiration, feeling spiritual and religious values, and more

Supporting

Ecosystem service - Maintain fundamental ecosystem processes that sustain life on Earth

Examples of supporting services

Photosynthesis providing oxygen and energy necessary for most living organisms, water cycling, biogeochemical cycling, and soil formation

Anthropogenic activities

Processes or actions that are human-caused and influence the environment, including the atmosphere, oceans, land, and ecosystems, and can disrupt ecosystem services which results in economic and ecological consequences

Examples of anthropogenic activities

Deforestation, burning fossil fuels, pollution, global warming, habitat loss, agriculture, invasive species, over exploitation, industrial waste, land use, over fishing, urbanization.

Island biogeography

The study of the ecological relationships and distribution of organisms on islands, and of these organisms’ community structures

Role of island biogeography in evolution

Promotes rapid diversification and the development of unique species through isolation, limited resources, and unique habitats that drive adaptive radiation. Causes species to evolve to be specialists due to limited resources.

Ecological tolerance

The range of conditions, such as temperature, salinity, flow rate, and sunlight, that an organism can endure before injury or death. Applies to individuals and species.

Natural disruptions

Natural events that have environmental consequences that may be as great as, or greater than, many human-made disruptions.

Short term natural disruptions

Events like hurricanes or wildfires that cause immediate, often localized, changes, with ecosystems typically recovering through ecological succession

Long term natural disruptions

Events like mass extinctions or ice ages, that unfold over long periods of time, leading to fundamental landscape changes, species shifts, and the potential for widespread population decline/ extinction

Periodic, episodic, random.

Categories of earth system processes

Periodic

Environmental processes that happen at regular, predictable intervals (tides, seasons)

Episodic

Environmental processes that occur at irregular but known intervals with significant impacts (volcanic eruptions, hurricanes)

Random

Environmental processes that are unpredictable and lack a discernible pattern or timeline (e.g., meteorite impacts). 

Sea level

The average height of the ocean's surface; has varied significantly as a result of changes in the amount of glacial ice on earth over time.

Swathes

Large, broad, or extensive areas of understanding, significance, or interpretation

Large swathes of habitat changes

Major environmental change or upheaval usually causes…

Short-term migration

The temporary movement of species from their usual habitat in response to a sudden event. The affected organisms typically return to their original location once the immediate threat has passed and conditions allow

Long-term migration

The permanent or sustained movement of people or animals from one region to another due to gradual, progressive changes in the environment

Adaptation

A change or the process of change by which an organism or species becomes better suited to its environment.

Reasons for adaptation

environmental changes, either sudden or gradual, may threaten a species survival, requiring animals to adapt or change to suit the new environment

Primary and secondary

Types of ecological succession

Primary succession

Ecological succession - a biological community gradually develops in a completely lifeless area, starting on bare rock or other substrates lacking soil

Secondary succession

Ecological succession - happens after a disturbance like a wildfire or logging has cleared an established ecosystem but left the soil intact, resulting in a much faster recovery because the soil already contains organic matter and nutrients

Ecological succession

The gradual process where plant and animal communities in an area change and are replaced over time, moving from simple pioneer species to more complex, stable climax communities.

Keystone species

An organism that has a disproportionately large impact on its ecosystem relative to its abundance, playing a critical role in maintaining its structure and biodiversity

Indicator species

An organism/species whose presence, absence or abundance reflects a specific environmental condition. By monitoring the abundance, health, and presence of these species, scientists can gain insights into ecosystem changes and make informed conservation decisions. 

Effects of succession

In a disturbed ecosystem: effects total biomass, species richness, and net productivity over time.