APES Unit 2: Species Survival, Tolerance, and Evolution

Ecological Tolerance

Refers to the range of abiotic conditions under which a species can survive, grow, and reproduce.

Law of Tolerance

Another name for Ecological Tolerance, highlighting the limits of environmental conditions for organisms.

Optimum Range

The ideal conditions at the peak of the tolerance curve that allow maximum survival and reproduction.

Zone of Physiological Stress

The area on the slopes of the tolerance curve where conditions are suboptimal and cause stress to the organisms.

Zone of Intolerance

The extremes on the ends of the tolerance curve where conditions are too harsh for survival.

Generalists

Species with a broad range of tolerance, allowing them to thrive in a variety of conditions.

Specialists

Species with a narrow range of tolerance, requiring specific environmental conditions to survive.

Adaptation

A genetic trait that enhances an individual's fitness in their environment, resulting from natural selection.

Natural Selection

The process whereby individuals with advantageous traits are more likely to survive and reproduce.

Selective Pressure

An environmental factor that influences which individuals survive and reproduce.

Structural Adaptations

Physical features of an organism's body that enhance its survival.

Physiological Adaptations

Internal processes or chemical activities within organisms that enable survival.

Behavioral Adaptations

Actions or activities of organisms that help them survive in their environment.

Extinction

The permanent loss of a species when it cannot adapt or migrate in response to environmental changes.

K-selected species

Species that reproduce slowly and have longer lifespans, adapting more gradually to environmental changes.

Rapidly reproducing species

Species that reproduce quickly, allowing for swift adaptation to changing conditions due to fast generation turnover.

Periodic Disruptions

Regular environmental changes that can affect ecosystems, such as tides and seasons.

Episodic Disruptions

Irregular environmental changes that occur occasionally, like hurricanes or El Niño events.

Random Disruptions

Unpredictable environmental changes such as meteor impacts or volcanic eruptions.

Acclimation

The temporary physiological adjustment of an individual organism to changes in its environment.

Genetic Diversity

The variety of genetic traits within a population, crucial for adaptation and evolution.

Misreading the Tolerance Graph

Confusing the axes of the tolerance graph, particularly the population size with abiotic factors.

Flexibility of Generalists

The ability of generalist species to adapt to diverse environments without being invasive.

Evolutionary Intention

The misconception that adaptations arise from an organism's needs or desires rather than random genetic variation.

Survival of the Fittest

The principle that individuals best suited to their environment are more likely to survive and reproduce.

Fitness

The ability of an organism to survive and reproduce in its environment.

Abiotic Factors

Non-living components of the environment, such as temperature, salinity, and sunlight, that affect ecological tolerance.