Ecological Classification and Food Chains

GAME

  • A game to understand ecological relationships and food chains.

Diatoms, Killer Whales, Copepods, Herring, Salmon

  • Various marine organisms featuring in the game.

GAME RULES

  • Tagging Mechanism:
       - Objective: Avoid being eaten by a predator.
       - You may only tag the organism that you "eat" in the food chain.
       - If tagged, organisms lose energy chips as follows:
         - Diatom → gives up 1 energy chip.
         - Copepod → gives up 2 energy chips.
         - Herring → gives up 4 energy chips.
         - Salmon → gives up 8 energy chips.

Results

  • Organisms and their corresponding energy circles accumulated:
      - Diatom
      - Copepod
      - Herring
      - Salmon
      - Killer Whale

ECOLOGICAL CLASSIFICATION

Lesson 8.3

Reflection on Consumption

  • Pear Deck Interactive Slide: Students encouraged to reflect on their dietary intake that day.

Interaction with Partners

  • Share dietary choices and discuss the original source of energy for the food consumed.

Ecological Classification

Trophic Level

  • Definition: The specific position an organism occupies in a food chain.

Ecosystem Structure

  • Autotrophs (Producers):
       - Define: Organisms that produce their own food through processes like photosynthesis.
       - Example: Phytoplankton.

  • Heterotrophs (Consumers):
       - Primary Consumers: Heterotrophs that feed on producers (herbivores).    - Secondary Consumers: Feed on primary consumers (carnivores).    - Tertiary Consumers: Feed on secondary consumers.    - Decomposers and Detritivores: Organisms that recycle nutrients by breaking down dead organic material.

Trophic Levels Explained

  • First Trophic Level (Primary Producers):
      - Example: Plants (e.g., Alpine meadow flora, phytoplankton).

  • Second Trophic Level (Primary Consumers):
      - Example: Herbivores (e.g., Butterflies).

  • Third Trophic Level (Secondary Consumers):
      - Example: Carnivores (e.g., Ravens, Weasels).

  • Fourth Trophic Level (Tertiary Consumers):
      - Greater carnivores (e.g., Mackerel, Tuna).

  • Examples of Decomposers: Bacteria, fungi, dung beetles.

Motivation Behind Consumption

  • Question for Discussion: Why do other organisms consume each other?

Energy Flow in Ecosystems

  • Key Concept: All energy flows through ecosystems in one direction, primarily from producers to consumers.

Autotrophs/Producers

  • Alternate Term: Autotrophs, which translates to "self-eating."

  • Process: Convert sunlight and CO₂ to organic material, enabling other life forms to derive energy.

Consumer Types

Primary Consumer

  • Description: Heterotrophs that feed directly on producers, considered herbivores.

  • Example Explanation: Basic level consumers in the food chain.

Secondary Consumer

  • Description: Heterotrophs that consume primary consumers; categorized as carnivores.

Tertiary Consumer

  • Description: Heterotrophs that primarily eat secondary consumers, emphasizing the multi-tiered nature of food chains.

Detritivore

  • Definition: Organisms that consume recently dead organic material.

Decomposer

  • Definition: Organisms that break down dead plant or animal matter, playing a pivotal role in nutrient cycling within ecosystems.

Classification Exercises

Student Exercises

  • Scenario Examples:
      - Leaf-eating ant?
      - Fox that eats rabbit?
      - Hawk that eats a lizard that eats insects?
      - Frog that eats flies?
      - Caterpillar that eats leaves?
      - Hawk that consumes a snake that preys on a mouse which feeds on grasshoppers?

Reflective Questions

  • What trophic level are plants at?

  • What is another word for producers?

  • What do we call animals that do not make their own food?

Food Chain

  • Definition: A direct, linear representation of feeding relationships within a community.

  • Example Task: Create a food chain using the following organisms: Rabbit, Grass, Coyote, and label their trophic levels.

Food Web

  • Definition: An extensive network of interconnected food chains within an ecosystem.

  • Note: Arrows indicate the direction of food movement.

Examples of Food Webs

  • Desert Biome Food Web:
      - Includes organisms like bacteria, tarantulas, rabbits, and hawks.

  • Grassland Food Web:
      - Features scavenger interactions (vultures), herbivores (zebras, elephants), and carnivores (hyenas, cheetahs).   

Practice Task

  • Create a food web using designated species from the next slide, ensuring it includes at least three food chains.

Final Activities

  • Work Time:
      - Complete Microbe Hunt Lab or EdPuzzle for homework.