How do species interact to generate stability in ecosystems?

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How do species interact to generate stability in
ecosystems?

• Community Interactions

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First, some termsHabitat vs. Niche

• A habitat is all the abiotic and biotic factors
  where an organism lives.
• A niche is comprised of all the physical,
  chemical, and biological factors a species needs
  to survive and thrive.
• Its like its role in the environment (how it
  lives within the habitat)
• Niche Includes place in the food web, tolerable
  abiotic conditions, and behaviors

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Community Interactions

• Community all interacting species of organisms
  in a given area
• Interactions among organisms can affect
  population growth and size, thus affecting other
  populations

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Community Factors that affect Overall Ecosystem
Health

• Diversity
• Richness, relative abundance
• Prevalent form of vegetation
• Dominant plants and their structure
• Stability
• Type of community, nature of disturbances
• Trophic structure
• Place in the food chain competition, predation,
  and symbiosis

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Types of InteractionsPredation

• Predation One animal eats and kills another
• Predator benefits from food.
• Prey benefits by eliminating non-adaptive genes
  from the gene pool.
• Prey adaptations may include chemical defenses,
  stings, camouflage, etc

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Types of InteractionsPredation

• Predator / Prey Graph
• Shows the cycling of prey and predator population
  sizes based on interactions with each other and
  quality of the habitat over time

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Types of InteractionsCompetition

• Competition Two organisms strive to obtain the
  same limited resource, and both are harmed to
  some extent
• Types of Competition
• Intraspecific same species compete
• Interspecific different species compete
• The more similar the competing species, the more
  intense the competition

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Types of InteractionsCompetition

• Competitive Exclusion Principle No two species
  can occupy the same ecological niche in the same
  place at the same time.
• If you are the less fit species, you must
  evolve into a slightly different niche, move, (or
  go extinct)

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Types of Interactions Symbiosis

• Symbiosis An overarching term for any
  interaction that involves a close, physical, and
  long-term relationship between two species. One
  species always benefits

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Types of Symbiosis

• Parasitism One organism, the parasite, lives in
  or on another organism, the host, from which it
  derives its nourishment

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Types of Symbiosis

• Commensalism One organism benefits while the
  other is not affected
• Eyelash mites
• Mutualism Both species benefit. In most cases
  one cannot exist without the other.
• Acacia ants