Objectives:1. Describe how groups of organisms interact2. Analyze different levels of organization in the

environment3. Recognize patterns found in groups of

organisms.

Ecology Chapter 2 Section 1

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.

A population is a group of organisms of the same species that live in a particular area.

Members of the same species that live in different areas belong to different populations.

A population can be a group of animals, plants, bacteria, fungus, or any living thing

Populations

Habitats and Niches

A habitat is the physical (specific) location of where organisms live.

Each habitat is filled with different species depending on its resources.

Different populations within a habitat will interact A niche is a role that living things plays in its

habitat. Generally no two species will fill the exact same

niche in a habitat.

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.

Communities

Patterns in Living Space These patterns will often show how a species meets

its needs. Ex. – Creosote bushes: release toxin into the soil so

no plants can grow near them. Closely packed herds of wildebeests help them

survive. They rely on their group for safety.

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.