An Introduction to Ecology

What is Ecology? = study of the interactions between living things and the physical environment

Levels of Ecological Study How do individuals interact with each other and their environment? How and why does population size change over time? Organismal – salmon migrate from saltwater to freshwater environments to breed Population - each female salmon produces thousands of eggs; only a few survive to adulthood, on average, only two will return to stream of their birth Community – salmon are prey as well as predators Ecosystem – salmon die and then decompose, releasing nutrients that are used bby bacteria, plants, young salmon and other organisms How do energy and nutrients cycle through the environment? How do species interact and what are the consequences?

Examine the set of pictures at your table. For each picture, consider… 1. Why are these organisms found in this particular environment? 2. What factors might determine the number of organisms found in this particular environment?

deep sea vent community Group 1 Tube worms in a deep sea vent community Coral and fish in the Great Barrier Reef

Largemouth bass in a stream community Group 2 Dolphin in an ocean community Largemouth bass in a stream community

Group 3 Polar bear in arctic community Grizzly bear in Canada

Bromeliad in tropical rain forest Group 4 Cactus in Arizona Bromeliad in tropical rain forest

Group 5 Trees Grass and shrubs

Why are Organisms Found Where They Are? (Biogeography) Abiotic Factors Biotic Factors Dispersal / Historical Factors

Abiotic Factors – Aquatic Ecosystems: 1. Nutrient Availability Wind blows along coastline; because the earth rotates constantly, this wind-driven water current is slowly moved offshore. As the surface water moves away from the coast, it is steadily replaced by water moving up from the ocean bottom; upwelling water is nutrient rich  helps recycle nutrients

Abiotic Factors – Aquatic Ecosystems: 1. Nutrient Availability Wind blows along coastline; because the earth rotates constantly, this wind-driven water current is slowly moved offshore. As the surface water moves away from the coast, it is steadily replaced by water moving up from the ocean bottom; upwelling water is nutrient rich  helps recycle nutrients

Abiotic Factors – Aquatic Ecosystems: 2 Abiotic Factors – Aquatic Ecosystems: 2. Water Depth / Light Penetration Light has major influence on productivity – the total amount of carbon fixed by photosynthesis per unit area per year

Abiotic Factors – Aquatic Ecosystems: 3. Water Movement

Biome = major grouping of plant and animal communities Abiotic Factors – Terrestrial Ecosystems 1. Precipitation and 2. Temperature Biome = major grouping of plant and animal communities

The World’s Biomes In your group… Summarize type of plant and animal life found in your biome Explain why these species are found there (precipitation and temperature)

Biotic Factors Tsetse fly carry a parasite that causes trypanosomiasis, which is fatal to cattle

Biotic Factors

Dispersal / Historical Factors

Dispersal / Historical Factors Kudzu, originally from Asia, is an invasive species

Why are species found where they are? In Summary… Why are species found where they are? Abiotic Factors Aquatic – nutrients, depth, flow Terrestrial – moisture and temperature Biotic Factors Dispersal / Historical Factors So how can we figure out what is playing the most significant factor in determining an organism’s range?

In Your Group… What question were they trying to answer? How did they attempt to answer the question? What did they find out?