Ecology Notes

INTRO TO ECOLOGY

ECOLOGY

  • ECO: "home"
  • OLOGY: "study of"
  • Definition: The scientific study of the interactions among organisms and between organisms and their environments.

ECOSYSTEM COMPONENTS

  • An ecosystem contains living and nonliving components.
    • Biotic Factors: "Living factors"
      • Include all living organisms (plants, animals, microbes)
    • Abiotic Factors: "Non-living factors"
      • Include all nonliving physical and chemical conditions (light, air, water, temperature, minerals, soil, climatic aspects)

LEVELS OF ECOLOGY

  • There are 5 levels of ecology:
    • Biosphere
    • Ecosystems
    • Communities
    • Populations
    • Individual Organisms
  • Increase in size/scope from individual organisms to the biosphere.

INDIVIDUAL ORGANISMS

  • The smallest unit of ecological study.

POPULATIONS

  • A group of individual organisms of the same species living together in a specific area.

COMMUNITIES

  • All of the organisms of all species that inhabit a particular area.

ECOSYSTEMS

  • Includes all of the biotic and abiotic factors in an area.

BIOSPHERE

  • Includes all of the ecosystems in the world.
  • The biosphere is the global ecosystem.

DESCRIBING ECOSYSTEMS

  • Habitat: Specific environment in which an organism lives.

DESCRIBING ORGANISMS

  • Niche: Unique living arrangement of an organism.
    • Defined by its habitat, food sources, time of day it is most active, and other factors.

SYMBIOSIS

  • Sometimes, different species make unique arrangements with one another called symbiosis.
    • "Sym-biosis" = "Together-Living"
    • Definition: Symbiosis is a close ecological relationship between the individuals of two (or more) different species.

SYMBIOTIC RELATIONSHIPS

  • Variety of symbiotic relationships:
    • Sometimes, a symbiotic relationship benefits both species.
    • Sometimes, one species benefits at the other's expense.
    • Sometimes, one benefits and the other doesn’t care!
    • In some cases, neither species benefits.

TYPES OF INTERACTIONS

  • Commensalism
  • Mutualism
  • Interspecific Competition
  • Predation
  • Parasitism

NEUTRAL INTERACTION

  • Neither species benefits or is harmed from the interaction.

COMMENSALISM

  • One species benefits, the other is unaffected.
  • Example: Barnacles

MUTUALISM

  • Both species benefit from the interaction.
  • Examples:
    • Rhizobium and Leguminous Plants
    • Clownfish and Sea Anemone
    • Bees and Flowers
    • Fig Wasps and Fig Trees
    • Gut Bacteria and Humans
    • Fungi and Algae (Lichen)

INTERSPECIFIC COMPETITION

  • Neither species benefit from the interaction.
  • Interspecific Competition: occurs between different species competing for the same resource.
  • Intraspecific Competition: occurs within the same species competing for the same resource.

PREDATION

  • One species (predator) directly harms the other (prey).
  • Example: Bobbit worm is a predator to the fish (prey).

PARASITISM

  • One species benefits (parasite), the other is harmed (host).
  • Examples:
    • Tick
    • Lice
    • Fleas
    • Roundworm
    • Whipworm
    • Hookworm
    • Tapeworm

SUMMARY CHART - Table of Interactions

  • Type of Interaction | Effect on Species 1 | Effect on Species 2
    • Neutral relationship | 0 | 0
    • Commensalism | + | 0
    • Mutualism | + | +
    • Interspecific Competition | - | -
    • Predation | + | -
    • Parasitism | + | -