Ecology Lecture Notes

Introduction to Ecology

• Definition: Study of how living things interact with each other and their environment.
• **Key Terms: **
  • Biotic Factors: Living components (e.g., plants, bacteria, animals).
  • Abiotic Factors: Non-living components (e.g., water, air, minerals).

Examples of Biotic and Abiotic Interactions

• Even in a room alone, you're surrounded by biotic factors like bacteria and plants.
• Interaction examples:
  • Plants produce oxygen, humans produce CO2.
  • Plants use sunlight for photosynthesis (abiotic interaction).

What Ecology Encapsulates

• Comprehensive study overlapping various biology fields.
• Focuses on higher-level interactions beyond individuals to populations, communities, and ecosystems.

Ecosystems

• Definition: Complex systems consisting of biotic and abiotic factors.
• Examples:
  • Coral reefs: coral, fish, bacteria (biotic); water temperature, salinity (abiotic).
  • Grasslands: trees, animals, insects (biotic); soil, humidity (abiotic).
  • Forests: mushrooms, trees, moss (biotic); sunlight, moisture (abiotic).

Scales in Ecology

1. Individual: One organism (e.g., a single elephant).
2. Population: Members of the same species in an area (e.g., herd of elephants).
3. Community: All living things in an area (e.g., elephants, giraffes, plants).
4. Ecosystem: All living things and their non-living environment (e.g., animals, plants, water, air).
5. Biosphere: All ecosystems connected on Earth.

Levels of Inclusion

• Biotic and abiotic factors interact and influence each other.
• Oxygen production and chemical composition changes are influenced by living organisms.

Concepts Beyond Earth

• Biosphere Examples:
  • Earth is the most known biosphere.
  • Man-made biospheres (e.g., space stations).
• Abiotic Influence: Sun and moon affecting life (e.g., sunlight, gravitational effects).

Ecological Fascinations

• Ecology studies complex, balanced, and sometimes imbalanced systems with emergent properties.
• Interaction dynamics can sometimes be observed at microscopic levels (e.g., bacteria on human skin).