2. Objectives: 1. Describe how groups of organisms interact 2. Analyze different levels of organization in the environment 3. Recognize patterns found in groups of organisms.

3. Organisms Occupy Specific Living Areas  Scientists group things according to their shared characteristics  The smallest grouping is the species.  A species is a group of closely related organisms that can breed and produce fertile offspring.

4. AA population is a group of organisms of the same species that live in a particular area. MMembers of the same species that live in different areas belong to different populations. AA population can be a group of animals, plants, bacteria, fungus, or any living thing

5. Habitats and Niches AA habitat is the physical (specific) location of where organisms live. EEach habitat is filled with different species depending on its resources. DDifferent populations within a habitat will interact AA niche is a role that living things plays in its habitat. GGenerally no two species will fill the exact same niche in a habitat.

6. A community is a group of populations that live in a particular area and interact with one another Ex. Wildebeests, gazelles, lions, and grasses all interact in a grassland.

7. Patterns Exist in Populations Populations settle themselves into living space in different ways. Populations may be crowded, be spread apart, or live in small groups. Ex. – Herring swim in schools, Wildebeests in closely packed herds Populations may also show a pattern over time. For example, the population size may change depending on the season.

8. TThese patterns will often show how a species meets its needs. EEx. – Creosote bushes: release toxin into the soil so no plants can grow near them. CClosely packed herds of wildebeests help them survive. TThey rely on their group for safety.

9. Patterns in Time  The population size of many different organisms may change over time.  Ex. – More wasps in the fall than in the spring.  Ex. – Birds migrate South for the winter.  Ex. - Some cicadas appear only every 17 years.