Resource Partitioning

Ecological Concepts

• The term "ecological niche" refers to an organism's resource use and functional role in the environment.
• "Resource partitioning" is a process that reduces competition by allowing organisms to use different methods for resource acquisition.

Evolutionary and Energy Processes

• "Character displacement" occurs when the evolution of physical characteristics among competing species leads to diversification.
• "Photosynthesis" captures energy from sunlight or chemicals and stores it in the bonds of sugars, serving as a primary energy source for ecosystems.

Consumer Categories

• Consumers that feed on dead and decaying organisms are known as "detritivores" or "decomposers."

Levels of Ecological Organization

• The levels of ecological organization, in order from smallest to largest, are: individual, population, community, ecosystem, biome, biosphere.
• A "population" is defined as a group of several organisms of the same species.

Ecosystems and Environments

• The term "ecosystem" encompasses all living (biotic) factors and nonliving (abiotic) factors in a physical environment.
• The term "community" describes all the different populations in a particular area.

Ecosystem Dynamics

• The difference between an "ecosystem" and the "biosphere" is that an ecosystem is a community of living organisms in conjunction with the nonliving components, while the biosphere includes all ecosystems on Earth.

Species Roles

• A "keystone species" plays a critical role in maintaining the structure of an ecological community, often having a disproportionately large effect on its environment relative to its abundance.
• The primary role of "pioneer species" in an ecosystem is to colonize previously disturbed or barren environments, facilitating ecological succession.

Invasive Species

• Nonnative species become labeled as "invasive species" primarily due to their ability to outcompete native species for resources and disrupt local ecosystems.

Ecological Succession

• The final stage of water succession is known as "climax community," which represents a stabilized ecosystem in equilibrium.

Population Dynamics

• The moderate decrease in the population size of Bald Eagles is often attributed to habitat loss and environmental pollutants.
• An age structure pyramid that is very wide at the bottom and narrows sharply as you move up indicates a growing "young" population.
• An aging population with fewer organisms in reproductive ages is likely labeled as "declining."

Demographic Information

• An "age structure diagram" displays the distribution of various age groups in a population.
• "Survivorship curves" describe how the likelihood of survival varies with age within a population.
• The basic difference between "density dependent" and "density independent" limiting factors lies in their relationship to population density; the former is affected by population size, while the latter is not.

Quiz on Resource Partitioning: Explore how organisms reduce competition by utilizing different methods to acquire resources. Learn about their niche and functional role in the environment through a descriptive image.