1. Levels of Ecology

1. Organism

   • One single living thing, like a bird, tree, or bug

   • How it survives and fits in its environment

2. Population

   • A group of the same kind of organism living together

   • Example: all the deer in a forest

3. Community

   • All the different living things in one place

   • Plants, animals, insects, fungi all together

4. Ecosystem

   • Living things plus non-living things

   • Example: fish, plants, water, rocks in a pond

5. Biome

   • Big areas of the world with similar weather and plants

   • Examples: deserts, rainforests, tundra

6. Biosphere

   • The whole Earth where life exists

2. Environmental Factors

1. Non-living (abiotic)

   • Temperature

   • Sunlight

   • Water

   • Soil

   • Air

   • Weather events like storms or fire

2. Living (biotic)

   • Animals that eat others

   • Animals or plants competing for food or space

   • Helpful partners like bees and flowers

   • Germs that cause sickness

3. Species Interactions

1. Competition

   • When living things want the same food, water, or space

2. Predation

   • When one animal hunts another

3. Herbivory

   • Animals eating plants

4. Symbiosis

   • Mutualism: both helpers benefit

   • Commensalism: one benefits, the other is not harmed

   • Parasitism: one benefits, the other is harmed

5. Helping without direct contact

   • One species makes life easier for another, like plants giving shade

4. Population Ecology

1. How populations grow

   • Fast growth

   • Slower growth when there is not enough space or food

2. What changes the number of animals

   • Births

   • Deaths

   • Animals moving in

   • Animals moving out

3. What affects growth

   • Things like too many animals in one place

   • Weather events like drought or storms

4. Types of species

   • Fast reproducers that have many babies

   • Slow reproducers that have fewer babies and take care of them more

5. Community Ecology

1. Important types of species

   • Dominant species: the most common

   • Keystone species: small but very important

   • Foundation species: shape the environment

2. Food levels

   • Producers: plants

   • Consumers: animals that eat plants or other animals

   • Decomposers: fungi and bacteria that break down dead things

3. Succession

   • How an area changes over time, like after a fire

4. Diversity

   • How many kinds of living things there are