1. Introduction to Ecology Part I
Ecology Unit
Introduction to Ecology
Part I

2. What is Ecology?
Greek oikos meaning “house” and logos meaning “ Study of”
Named in 1866
Is the study of the interactions between organisms and the living and nonliving components of their environment

3. What is Interdependence?
Organisms that are dependent on one another and their environment
Interdependence is a key theme found throughout ecology
Example 1: you could not survive without the plants and other photosynthetic organisms that produce oxygen
Example 2: Plants could not survive without carbon dioxide (essential raw material for making carbohydrates by photosynthesizers

4. Effects of interdependence:
Any change in the environment can spread through the network of interactions and affect organisms that appear far removed from change
Large acorn production can support large deer and mice populations. Tick feeds on animals, so they increase; increasing the chance of humans being bit (Lyme disease)

5. Levels of Organization in Ecology
1. The Biosphere:
The broadest level of organization
The thin volume of Earth and its atmosphere that supports life
Where all organisms are found
13 miles thick (if the Earth was the size of an apple, the biosphere would be the thickness of its skin)

6. Levels of Organization in Ecology
2. Ecosystems:
Includes ALL of the organisms and the nonliving environment found in a particular place
Organisms in every environment directly or indirectly affect one another.
Chemical composition will also affect species in every ecosystem

7. Levels of Organization in Ecology
3. Communities:
Includes only species of organisms
Is all the interacting organisms living in an area
Ex: Fish, turtles, plants, and bacteria in the pond that makes up a community

8. Levels of Organization in Ecology
4. Populations:
Includes all members of a species that live in one place at one time
Ex: Population of California poppies (flowers) in a specific area of California

9. Levels of Organization in Ecology
5. Organisms:
Is the simplest level of organization in ecology
Research concentrates on the adaptation that allows organisms to overcome the challenges of their environment

10. Biotic vs Abiotic Factors:
The physical and chemical aspects of the habitat
They are all the nonliving factors
Include: temperature, humidity, pH salinity, oxygen concentration, sunlight, nitrogen, and precipitation (water)
These factors vary from place to place

11. Biotic vs Abiotic Factors:
All the living components of the environment
Include all living things that affect the organism

13. Biotic vs Abiotic Factors:
***Draw and Label four abiotic and biotic factors***

14. Niche: What is a niche’s meaning? What is a niche?
French nichier, meaning “to nest”
What is a niche?
Is the specific role, or way of life, of a species within its environment

15. Niche: Niche includes the following:
The range of conditions that a species can tolerate
The resources it uses
Methods by which it obtains its resources
The number of offspring it has
Time or reproduction rate
And all other interactions within its environment

16. Niche: Some species have more than one niche in their lifetimes:
Ex: Caterpillars eat leaves of plants. As an adult, butterflies feed on nectar

18. Two classes of a niche: Generalist: Are species with broad niches
They can tolerate a range of conditions and use a variety of resources
Ex: Virginia opossum – found across most of the U.S. Feeds on almost anything.

19. Two classes of a niche: Specialists: Have very narrow niche
Example: Koala, in Australia, only feed on the leaves of a few species of eucalyptus trees

20. Niche
***Draw and label a niche***

21. Key questions/concepts to review
Explain why interdependence is an important theme in ecology?
Describe one example of the effects of interdependence upon organisms in their environment?
List and describe the key components of the 5 main levels of organization in ecology

22. Key questions/concepts to review
Why is the amount of sunlight important to the animals in an ecosystem?
Assuming wolves eat deer, how could a disease that kills a large portion of the wolf population affect the mice population in a forest ecosystem?

23. Key questions/concepts to review
Distinguish between biotic and abiotic factors. List several examples
Compare generalists to specialists
How does an organism’s niche differ from its habitat

24. Key questions/concepts to review
Why do different species never occupy exactly the same niche?
If some of the resources in a habitat are destroyed, which would be more likely to survive, a generalist species or a specialist species? Explain your answer