Food Chains

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Food Chains Food Webs
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What is a food chain?

• A Linear depiction of the transfer of energy
  from one organism to another as each is eaten.
• This is the typical depiction beginning with
  photosynthesis at the bottom and ending with a
  large carnivore at the top of the chain.
• Note linear and incomplete (no people or
  decomposers)

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What is a food web?

• A more accurate depiction of the interaction
  among the members of an ecosystem
• Shows that individual organisms might have
  multiple food sources and multiple predators
• Note Non-linear Includes conditions necessary
  for photosynthesis and decomposers, but still no
  people

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Great activity for kids

• Construct a food web for the organisms in your
  schoolyard, neighborhood, city, or state.
• Requires direct observation or research into the
  plant and animals of the community.
• Requires understanding of the multiple
  interactions among the members.
• Would almost certainly include the human factor.

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Step 2 of great activity for kids

• Have them add or remove, increase or decrease one
  organism in their web.
• Construct a plausible explanation about what
  would be the factors that might cause this
  change.
• Discuss the short-term and long-term effects this
  change might have upon the other organisms and
  the entire web. (Possibly redraw the web to
  reflect these changes)
• Discuss how this change might be enhanced (if it
  seems to improve the web) or be avoided (if it
  seems a detriment to the web).
• Discuss how this relates to the world web as a
  whole and what our individual, community, and
  national responsibilities might be towards the
  ecosystems we affect.

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A fun computer simulation

• Quick interactive game Plants, Rabbits, and
  Foxes http//puzzling.caret.cam.ac.uk/game.php?gam
  efoodchain

A fun non- computer simulation

• A non-technical interactive game
• From the Sept. 23rd Webinar
• Oh Deer PowerPoint

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For further information and ideas, check these
out on the Wiki

• IRC Food Chains and Food Webs
• IRC Producers, Consumers, and Decomposers
• IRC Interactions within Ecosystems
• IRC Environmental Conditions that Affect
  Survival and Adaptations
• IRC Human Contributions to Extinctions of Some
  Species