Species, Populations and Communities

Species, Populations and Communities

Standards

L.5.3B students will demonstrate and understanding of a healthy ecosystem with a stable web of life and the roles of living things within a food chain and/or food web, including producers, primary or secondary consumers, and decomposers

L.5.3B.2 Develop and use a food chain model to classify organisms as producers, consumers, or decomposer. Trace the energy flow to explain how each group of organisms obtains energy.

Limiting Factors:

The number of organisms in a population depends on the amount of resources available. Because resources limit the population, they are called Limiting Factors. They include:

Limiting Factors

• Water

• Sunlight

• Food

• Living Space

limiting Factors

Organisms compete for these resources and depend on them for survival. In order to survive, every organism finds its own niche, or role in the community.

An organism's niche includes:

• What and When it eats

• When it's active

• What it uses for shelter

• How it Reproduces

Important Vocabulary

• Ecosystem

• Food Chain

• Food Web

• Habitat

• Prey

• Fungi

• Bacteria

• Population

• Producers (Primary and Secondary)

• Decomposers

• Predator

• Host

• Limiting Factors

• Herbivore

• Carnivore

• Omnivore

• Niche

• Biome

• climate

• Scientific Method

• Observations

Levels of Organization in an Ecosystem

Ecosystem can be broken down into levels (from smallest to largest):

Levels of Organization

• Organism

• Population

• Community

• Ecosystem

• Biome

• Biosphere

Levels of Organization

• Organism: one member of a population (a single lake trout in Lake Michigan).

• Population: the total number of one type of organism (a species) in a certain area (all the lake trout in Lake Michigan)

• Community: all of the populations that interact in an area (the different types of fish, bacteria, leeches, water bugs, algae, and plants that live in Lake Michigan).

• Ecosystem: all of the communities and nonliving factors in an area (Lake Michigan as a whole).

• Biome: a region that can include a number of ecosystems (the temperate deciduous forest)

• Biosphere: all the ecosystems on Earth combined.

Levels

The living things in any ecosystem can be organized into groups. The most specific group an organism can be classified into is a Species. For example, there are many different kinds of cats, but the lion is one particular species of cat. In an ecosystem, a Population includes all members of a single species in an area at a given time. In a desert ecosystem, all of the saguaro cactus plants form a population. The sidewinder, diamondback, and tiger rattlesnakes are different species that all form separate populations of rattlesnakes in the desert ecosystem.

Levels

Together, all of the populations in an ecosystem make up a community. A pond community may have populations of ducks, bullfrogs, fish, water lilies, and dragonflies. In addition to plants and animals, a community has populations of bacteria, protists, and fungi such as mushrooms. For example, a forest community has huge populations of mold and bacteria living in its soil. The size of a community depends on its abiotic factors such as shelter, water and light, as well as the among of food that is available. A living community may cover a huge area and include thousands of populations.

Quick question???

What are the Levels of the Ecosystem?