Ecology Ecology is the scientific study of the interaction between organisms and between organisms and their environment.

How do animals benefit plants?

What non-living things in their environment do organisms interact with?

Levels of Organization 1. Biosphere 2. Biome 3. Ecosystem 4. Community 5. Population 6. Organism

Can a group of rabbits and a group of field mice make up the same population?

Could a biome near Brazil be the same as a biome in northern Canada?

Ecosystems An ecosystem consists of a given area’s (______________) and (______________). physical features abiotic factors living organisms biotic factors 7

Abiotic factors nonliving physical parts of an ecosystem such as _______________ type, rocks, temperature, _______________, and rainfall. water, sunlight, soil humidity, elevation Wind: Can affect the pattern of a plant’s growth 8

Biotic Factors living aspects of an ecosystem such as_____________ _______________, worms, amoebas, and waterlilies. fishes, frogs, insects, snails, 9

Habitats Ecosystems contain Habitats, the location or surrounding where the organism lives 10

Niches, the behavior of organisms in their habitats. 11

Community organisms living together in an ecosystem 12

Ecological Methods Scientists conduct research using 3 basic approaches. 1. Observing – could be behavior observations about an animal. 2. Experimenting – test a hypothesis 3. Modeling – gain insight into complex phenomena like global warming.

Notes: 3-2 Energy Flow Sunlight is the main energy source for life on Earth. Autotrophs – capture energy from sunlight and use that energy to produce food. Also called producers.

Producers Photosynthesis is responsible for adding oxygen to—and removing carbon dioxide from—Earth's atmosphere. Sunlight is the main energy source for life on Earth. Some types of organisms rely on the energy stored in inorganic chemical compounds. Plants use the energy from sunlight to carry out the process of photosynthesis.

Heterotrophs – rely on other organisms for their energy and food supply. Also called consumers. Herbivores – eat plants Carnivores – eat animals Omnivores – eat both Detritivores – eat dead matter (mites, worms, snails, crabs

Food Chains Food Chains – a series of steps in which organisms transfer energy by eating and being eaten. Example: plankton –dragonfly-salamander-snake

less stable and more easily destroyed C. Feeding Relationships 1. Food chain: a. chains are found in harsh climates like the desert and tundra . b. Desert or tundra areas are than those found in more moderate climatic influences e.g. follow the progression of energy flow from one organism to another or “who eats whom.” shorter food less stable and more easily destroyed tropical rain forests. 18

Food Web Food Web – links all the food chains in an ecosystem together.

Trophic Level Each step in a food chain/web is called a trophic level. (herbivore)

Pyramids – 3 types 1. Energy Pyramid – transfer of energy from one trophic level to the next. Measured in kcals. **10% rule** - only 10% of the energy is transferred from one trophic level to the next. Why? It is lost in respiration, movement and reproduction.

Ecological Pyramids 0.1% Third-level consumers 1% Second-level consumers 10% First-level consumers 100% Producers Ecological pyramids show the decreasing amounts of energy, living tissue, or number of organisms at successive feeding levels. The pyramid is divided into sections that represent each trophic level. Because each trophic level harvests only about one tenth of the energy from the level below, it can support only about one tenth the amount of living tissue.

How about the second-level consumers that at the mice and insects? Suppose that the base of an energy pyramid consists of plants that contain 450,000calories of food energy. If the plants were eaten by mice and insects, how much food energy would be available to those first-level consumers? How about the second-level consumers that at the mice and insects? How about the third-level consumer?

First-level consumer would have 45,000 calories available Second-level consumer would have 4500 calories available. Third-level consumer would have 450 calories available.

Feeding Relationships Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers).

Energy Pyramids Cont’d 100 K/cals 1,000 K/cals 10,000 K/cals

Types of Pyramids 2. Biomass Pyramid – transfer of biomass from one trophic level to the next.

Types of Pyramids 3. Pyramid of Numbers – the total number of individuals at each trophic level. (may not look like a pyramid)