KEY CONCEPT Food chains and food webs model the flow of energy in an ecosystem.

Notice the arrows. Are they pointing in the right direction? DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK Why would the arrows be pointing in this direction?

The arrows point in the direction that energy flows!!!! DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK The Desert Cottontail gets its energy FROM the Grama grass The Harris’s Hawk gets its energy FROM the rabbit

A food chain is a model that shows a sequence of feeding relationships. A food chain follows the connection between one producer and a single chain of consumers within an ecosystem. DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK

A food web emphasizes complicated feeding relationships and energy flow in an ecosystem.

Arctic Marine Food Web

African Grassland Ecosystem

Desert Ecosystem

Wetland Ecosystem

Chaparral Food Web

Temperate Forest Ecosystem

Create-A-Food Web Pg. 410 Must have a title Producers must form the base of the web Arrows show direction of energy flow Organisms must have multiple feeding relationships Label each organism (Bird, wolf…) Label producers/consumers

Food Web: Bill Nye (21m)

At your table please describe these types of consumers: Herbivores? Carnivores? Omnivores? Detritivores? Decomposers?

Consumers are not all alike. Herbivores eat only plants. Ex: grasshopper Carnivores eat only animals. Ex: Lion Omnivores eat both plants and animals. Ex: Bears Detritivores eat dead organic matter, including feces (not including scavengers) Ex: Worms, slugs, sea stars, some flies, millipedes Decomposers are detritivores that break down organic or dead matter into simpler compounds. Ex: bacteria, Fungi carnivore decomposer

Specialists are consumers that primarily eat one specific organism (they only eat one thing) Ex: Bamboo is 99% of a panda’s diet Generalists are consumers that have a varying diet (they eat a lot of different things) Ex: Gray wolf eats elk, moose, deer, and mice

Trophic levels are the nourishment levels in a food chain.

Tertiary consumers: Carnivores that eat carnivores Ex: owl eating a mole ENERGY Secondary consumers: Carnivores that eat herbivores Ex: mole eating a grasshopper Primary consumers: Herbivores that eat producers Ex: grasshopper eating grass Producers: Produce their own food Ex: plants

Omnivores, such as humans that eat both plants and animals, may be listed at different trophic levels in different food chains. If you are eating a salad you are….? a primary consumer (omnivore eating a producer) If you are eating a hamburger you are….? a secondary consumer (omnivore eating a herbivore) If you are eating shark soup, you are….? a tertiary consumer (omnivore eating a carnivore)

Balance Within A Food Chain (4m14s)

Finish: Create-A-Food Web Pg. 410 Color code and label if it is a producer and/or type of consumer Producer Primary consumer Secondary consumer Tertiary consumer MUST HAVE A KEY!!!

Create-A- Trophic Level Pyramid Homework Create-A- Trophic Level Pyramid Pg. 86 (On your own) Think of an example of a food chain Create a trophic level pyramid using this food chain Include an Example of a(n): producers primary consumers secondary consumers tertiary consumers Make it realistic!