Principles of Principles of EcologyEcology

Chapter 15 and 16Chapter 15 and 16

What is Ecology?What is Ecology?

• Ecology: the study of interactions among organisms and living and nonliving components of their environments.– Reveals relationships among living and non-

living parts of the world– Observed both in the lab and the

environment

What would an ecologist study or look for in the environment?

Aspects of Ecological StudyAspects of Ecological Study

• Biosphere: portion of the earth that supports life.

– Includes:

• Atmosphere

• Hydrosphere: Oceans and Lakes

• Lithosphere:Terrestrial Earth

• Ecosphere:All living organisms

Non-Living EnvironmentNon-Living Environment• Abiotic Factors: non-living parts of an organism’s

environment

Examples:• Air & Water Temperatures• Moisture & Precipitation• Light• Soil• Wind

Why are abiotic factors important in ecology?

How do they effect living organisms?

Importance of Water!

• Why introduce water as something we should study?

• Because all living things need water!

• We will be studying how the properties of water effects what can live there.

Where’s all the water?

• Oceans: 97.2 %

• Icecaps and Glaciers: 2.0 %

• Groundwater: 0.62%

• Atmosphere: 0.001%

• Freshwater: 0.0009%

• Rivers: 0.0001%

Can’t Use!

Useable Freshwater

Living EnvironmentLiving Environment

• Biotic Factors: all the living things that inhabit an environment.

Examples: look familiar?• Animals• Plants• Fungi• Protists• Bacteria

Levels of Ecological OrganizationLevels of Ecological Organization

Biosphere (most diverse)

Ecosystem

Community

Population

Individual (single organism)

Levels of Ecological Levels of Ecological OrganizationOrganization

• Individual:– Made of cells– Uses energy (food)– Reproduces– Responds and adapts– Grows and develops

What do we know these as?

Levels of Ecological Levels of Ecological OrganizationOrganization

• Population: A group of organisms

that:

– Are all the same species– Interbreed– Live in the same area at the

same time

– Members of a population may compete with each other for:

• food, water, mates, or other resources

Levels of Ecological Levels of Ecological OrganizationOrganization

• Community:– Made of interacting populations in a certain area at

a certain time

– In a community a change in one population may cause changes in other populations

How can one population influence other populations?

Levels of Ecological Levels of Ecological OrganizationOrganization

• Ecosystem: – Is made up of interacting populations in a biological

community and the community’s abiotic factors

2 kinds:

• Terrestrial– Forest, desert, grassland, tundra, mountains

• Aquatic– Pond, lake, river, deep ocean, reef, estuary

What level is this?What level is this?

Organisms in Ecosystems

• Habitat: the place where an organism lives out its life

– Examples: grasslands, trees, muddy banks

• Niche: the role and position a species has in its environment

– How it meets the needs for survival

– Includes all interactions with the biotic and abiotic parts of its habitat

NicheNicheExamples:

– On forest floor there is competition for food and space:

• Millipedes – eat decaying leaves

• Centipedes – eat beetles and other animals

• Ants – eat dead insects

• Earthworms – take organic nutrients from the soil

• Fungi – take nutrients from decaying organic material

Living RelationshipsLiving Relationships

• Some species increase their chance of survival by developing relationships with other organisms

• Some interactions are harmful to one species, others are beneficial

Relationships cont.Relationships cont.• Predator – Prey relationship

– Predator: animals that consume other animals

– Prey: animals that are consumed

• Examples:

– Lions & wildebeests

• Symbiosis: “living together”

– relationship in which there is a close and permanent association between different species

Relationships cont.Relationships cont.

• Commensalism– relationship in which one species benefits, while

the other species is neither benefited nor harmed

• Examples:

– Sea anemone & clownfish

– Shark & remora fish

Relationships cont.Relationships cont.• Mutualism:

– Both species benefit from the relationship• Examples:

– Ants and acacia trees

– Hammerhead sharks & cleaner fish

• Parasitism:– One species benefits while the other is harmed

• Examples:

– Fleas and dogs

– Ticks and deer

– Tapeworms and humans