Warm up

• What is an ecosystem?

• What is a community?

Warm up

• What is an ecosystem?• What is a community?– One of the main points about an ecosystem is the

interaction between biotic and abiotic factors. – A community is groups of populations interacting

with one another.

Investigation 4, Part 2

Mono Lake Food Web

Objective

• Students will understand food webs as evidenced by completing an accurate portrayal of the Mono Lake Food web

Mono Lake

• One way the organisms in the Mono Lake system interact is by eating each other. (Nom, nom….Lunch!)

• This is called a feeding relationship.• I have sets of cards of important organisms from Mono

Lake.• Each card contains:

– Photo– Common and scientific name– Life cycle and population dynamics– How it gets food– It’s role in the ecosystem

Mono Lake Cards

• Organize the cards, picture side up.• Use the arrow strips to show feeding

relationships between the organisms. (Who eats who?)

• Every organism should be included in this chart.

• If an organism is involved in more than one feeding relationship, indicate that with more than one arrow

Arrow Direction

• Do spiders and flies have a feeding relationship?

• Who gets eaten?

• How do you represent that relationship?

– Fly Spider

Arrow Direction

• Do spiders and flies have a feeding relationship? – Yes

• Who gets eaten?– The spider eats the fly

– Fly Spider

– The arrow goes from the fly to the spider even though the spider eats the fly. The arrow represents the energy of the fly going into the spider.

You may begin

This is what your web should have displayed

Food Chain

• In an ecosystem, many organisms survive by eating other organisms.

• The benefits of the food eaten by one organism can then move to one and then another organism as each one is eaten.

• The path that food takes from one to another organism is called a food chain.

• Draw the arrows in:

• Planktonic aglae Brine shrimp

• California Gull Coyote

Food Web

• I saw lots of organisms in your groups that were connected by more than one arrow.

• Some organisms like phalaropes eat more than one organism.

• Some organisms like brine shrimp are eaten by many organisms.

• When you connect all the arrows, the arrows cross each other in complicated ways.

• A diagram that shows all the feeding relationships is called a food web.

Types of Organisms Questions

• What types of organisms do not eat other organisms?

• How do they survive with out eating?

• Organisms that make their own food are producers. They make food that is consumed in an ecosystem.

• In the Mono Lake ecosystem, the producers are algae.

Types of Organisms Answers

• What types of organisms do not eat other organisms?– The two kinds of algae

• How do they survive with out eating?– All living things need food/energy to survive, so they

must make their own. • Organisms that make their own food are producers.

They make food that is consumed in an ecosystem.• In the Mono Lake ecosystem, the producers are

algae.

Types of Organisms

• Producers like algae make their own food, but animals like brine shrimp and gulls do not.

• How do brine shrimp and gulls get food?

• Organisms that eat other organisms are called consumers.

There are many types of Consumers:

• Take out your journal and jot some notes about these:

• Primary or first level consumers• Secondary or second level consumers• Tertiary or third level consumers• Fourth Level consumers

Types of Consumers

• Consumers that eat producers are primary or first-level consumers.

• Which animal is the primary consumer?

• Consumers that eat primary or first-level consumers are secondary of second-level consumers.

• Consumers that eat secondary or second-level consumers are tertiary or third-level consumers.

• Consumers that eat tertiary or third-level consumers are fourth-level consumers.– And so on……..

Another Type of organism

• Some things never get eaten. • They die natural deaths.• These dead organisms are broken down and

consumed by microorganisms called decomposers.

• Bacteria and fungi are decomposers. • Everything that is not eaten by a consumer is

eventually eaten by a decomposer.

Revisit your Food Web

• This time show the LEVEL of the organisms in your web.

• Producers on the bottom.• Primary consumers are the next level up, etc…

Some are Tricky

• Red-necked phalaropes– Eat both brine shrimp and brine flies making them

secondary consumers.– Also eat planktonic algae making them primary

consumers.

Another Tricky example

• California gulls– Eat mostly brine shrimp and flies.– Given the chance will eat eggs and chicks of snowy

plovers and Caspian terns.

Question:

– How can we show these dual roles on our charts?– What about decomposers? How should we show

them?

Finish up Lab sheet 21.

Wrap up

• Let’s talk about the questions on the sheet