Unit 2: The Living World - Biodiversity

Biodiversity

The variety of life in a particular habitat or ecosystem, encompassing three levels: genetic, species, and habitat diversity.

Genetic Diversity

The measure of genetic variation among individuals in a population.

Species Diversity

The number of different species in a given area, encompassing species richness and species evenness.

Species Richness

The total number of different species present in a specific area.

Species Evenness

The relative abundance of each species in an ecosystem.

Habitat Diversity

The variety of habitats that exist within a specific region.

Population Bottleneck

A sharp reduction in the size of a population due to environmental events or human activities.

Consequence of Bottleneck Effect

Reduced genetic diversity leading to inbreeding and increased vulnerability to diseases.

Generalist Species

Species that can thrive in a variety of environments and have a broad diet.

Specialist Species

Species that are adapted to a very specific diet or habitat.

Shannon-Wiener Index

A formula used to quantify biodiversity considering both species richness and evenness.

Provisioning Services

Products obtained from ecosystems like lumber, water, and food.

Regulating Services

Benefits obtained from ecosystem processes that regulate natural systems.

Cultural Services

Non-material benefits gained from ecosystems, such as recreation and aesthetic experiences.

Supporting Services

Services vital for the production of all other ecosystem services, such as soil formation and nutrient cycling.

Theory of Island Biogeography

A theory that explains the ecological relationships and community structures of organisms on islands.

Distance Effect

The concept that closer islands to the mainland experience higher immigration rates of species.

Size Effect

The idea that larger islands support more species due to more available resources.

SLOSS Debate

The discussion surrounding whether a single large reserve is better than several small reserves for conservation.

Range of Tolerance

The spectrum of abiotic conditions a species can withstand.

Zone of Intolerance

Conditions that are too extreme for a species, leading to death.

Limiting Factor

An abiotic factor that is in short supply, restricting population growth.

Periodic Change

Natural ecosystem change occurring at regular intervals.

Episodic Change

Natural ecosystem change occurring occasionally and irregularly.

Primary Succession

The process of community change that begins in a lifeless area with no soil.

Secondary Succession

The process of community change that occurs in an area where a disturbance has cleared the community but soil remains.

Keystone Species

A species that has a disproportionately large impact on its ecosystem relative to its abundance.

Indicator Species

An organism that indicates specific environmental conditions through its presence or absence.

Anthropogenic Threats

Human-induced pressures on biodiversity, summarized by the acronym HIPPCO.

HIPPCO

A mnemonic for Habitat destruction, Invasive species, Population growth, Pollution, Climate change, Overexploitation.

Natural Selection

The process whereby organisms better adapted to their environment survive and reproduce more successfully.

Ecological Succession

The gradual process in which ecological communities change over time.

Optimal Range

The range of environmental conditions under which a species thrives.

Zone of Physiological Stress

A range of conditions where a species survives but experiences stress.

Adaptation

The process through which a species evolves traits to better survive in its environment.

Genetic Variation

The diversity of gene variants within a population.

Climate Change

Long-term alteration of temperature and typical weather patterns in a place.

Ecosystem Services

Benefits that humans receive from ecosystems, such as clean water and pollination.

Nutrient Cycling

The movement and exchange of organic and inorganic matter back into the production of living matter.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

Natural Disruptions

Changes in ecosystems caused by natural events like climate variations, meteorite impacts, or volcanic eruptions.

Overharvesting

The excessive use of natural resources leading to depletion.

Invasive Species

Non-native species that spread widely in a new environment and disrupt local ecosystems.

Pollination

The process by which pollen is transferred from the male part to the female part of plants for fertilization.

Ecosystem Engineers

Organisms that significantly modify their environment, impacting ecological community structure.

Bell Curve

A graph depicting a normal distribution of values, commonly used to illustrate the range of tolerance.

Soil Formation

The process of developing soil through the weathering of rocks and the accumulation of organic matter.