Ecology

1. Ecology Study of interactions between organisms and their environments.

2. Biotic Factors • Biosphere – life-supporting layer of Earth • Biotic factors – all living organisms in a biosphere

3. Abiotic Factors • Nonliving factors in an environment • Examples: • Air currents • Temperature • Moisture • Light • Soil

4. Where they all belong… • Habitat—the natural home or environment of an animal, plant, or other organism. • Niche—a position or role taken by a kind of organism within its community. Antelope Habitat: grassland, savannah, etc. Niche: primary consumer Kangaroo Habitat: woodlands, grassy plains Niche: primary consumer

5. Levels of Organization

6. Feeding Relationships (trophic levels) • Producers–Autotrophscapture energy from sunlight • Consumers– Heterotrophs rely on other organisms for energy • Herbivores – eat only plants • Carnivores – eat animals • Omnivores – eat living plants and animals • Detritivores -eat dead plants and animals

7. Trophic Relationships (or niches) • Producer—autotroph whichcaptures energy from sunlight • Primary consumer (herbivores, detritivores)—gets energy from eating producers examples—deer, pill bugs • Secondary consumer (carnivores, omnivores, detritivores)—get most or all energy from eating primary consumers examples—fox, raccoon, catfish • Tertiary consumers (carnivores, detritivores)—get most or all energy from eating secondary consumers examples—eagles, vultures • Quaternary consumer—top level (apex) predators that eat all consumers but have no natural predators examples—orcas, lions • Decomposers—break down organic matter (leftovers of dead plants and animals) examples—fungi, bacteria

8. Random but interesting fact…what about mummies?

9. Trophic Relationships • Food chain – a series of steps in which organisms transfer energy by eating and being eaten • Food web –the feeding relationships that form a network of complex interactions (more realistic…why?) • Trophic level – each step in a food chain or food web

10. Food Web 4 Quaternary consumers 2 3 1

11. Community Interactions • Mutualism—both species benefit from therelationship Examples—rhino & oxpecker, E. coli & human gut • Commensalism—one organism benefits and the other is neither helped nor harmed Examples—clownfish & sea anemones, spanish moss growing on trees • Parasitism—one organism benefits and the other is harmed Examples—tapeworms in your intestines, wasp larvae in caterpillar

12. Ecology Pyramids • Energy pyramid – shows the relative amount of energy available at each trophic level Sunlightis the main source of energy. Energy passes from one level to another in only one direction. Matter passes from level to level in a cycle (the circle of life).

13. Biomass pyramid – represents the amount of living organic matter at each trophic level

14. Pyramid of numbers – shows the relative number of individual organisms at each trophic level

15. RULE OF 10 (why there are more producers than consumers) • Only 10% of energy is transferred from one trophic level to the next. • Example: • It takes 100 kgs of plant materials (producers) to support 10 kgs of herbivores • It takes 10 kgs of herbivores to support 1 kg of 1st level predator • The other 90% is used up in life processes or released as heat