1. Studying Ecology Chapter 4 Section 1

2. Levels of Ecological Organization
Ecologists study life at many levels.
Ecology is the study of how organisms interact with each other and their environments .
Individual
Species
Population
Community
Ecosystem
Biosphere
Cells
Tissue
Organs
Organ Systems
Individual Species
Atoms
Simple Molecules
Macro-
molecules
Organelles
Cells

3. Individual Species/Organism
Basic level of study for an ecologist is an individual organism.
Ecology describes the relationship between organisms and their environment.
A species is a group of individuals that…
interbreed and produce fertile offspring.
have genetic similarity

4. Populations
Population: members of the same species that live in the same area at the same time.
The fleas living on your dog = a population.
All of the golden toads in the Costa Rican rainforest = a population.

5. Communities All of the populations in a particular area.
PA bears’ community includes:
Plants and trees
Other animals
Fungus
Stream life

6. Ecosystems
An ecosystem includes all of the living things in an area AND their physical environment.
Back to the bears…Their ecosystem would including the following…
Air
Trees
Soil
Nutrients
Rivers

7. Biosphere All of the parts of Earth that host life.
all of the organisms and environments in which they live.
Ecologists rarely study this “grand” of a scale!

8. Let’s Fill Out Our Diagram With Examples!

9. Biotic vs. Abiotic Biotic Factors Abiotic Factors
Living parts of ecosystem or were “recently” alive.
Examples: leaves, trees, fallen logs, carrion (decomposing animals)
Ecosystem parts that have never been living.
Many are used or consumed by living things.
Examples: oxygen, sunlight, water, carbon.

10. Habitat The environment in which an organism lives
Includes all the resources needed to survive.
Include both abiotic and biotic factors, because both are required for living things to survive.

11. Review Questions
Would all of the different kinds of organisms in a pond be considered a population or a community? Explain.
For each level of ecological organization (refer to your chart) state whether it contains only biotic factors, only abiotic factors, or both.