Field of BeansDetermining the Interactions of Organisms

TEKS 8.11A – Describe producer/consumer,

predator/prey and parasite/host relationships as they occur in food webs.

7.5C – Diagram the flow of energy through living systems, including food chains, food webs and energy pyramids.

Objectives Estimate the size of various populations

Create a food web and

Construct pyramids of energy of organisms within a terrestrial ecosystem.

Field of Beans

Pre-Lab

Producers/Autotrophs Plants that make their own food through

photosynthesis by the Sun’s energy.

Consumers/Heterotrophs Animals that have to eat other

organisms for food to get energy.

3 Types of Consumers

Herbivores – Animals that only eat plants

Omnivores – Animals that eat plants and other animals

Carnivores – Animals that only eat other animals (meat)

Decomposers/Saprotrophs Organisms that

feed on and get energy from decaying organic matter (excrement and dead organisms)

Speeds up the decaying process and puts nutrients back into the soil.

Food Chain Simple model that shows one pathway

of how matter and energy move through an ecosystem.

Energy Pyramid An ecological

pyramid that shows the flow of energy between organisms within an ecosystem.

Types of Pyramids

Trophic Level The position in a

food chain or energy pyramid that an organism occupies based on what it eats.

Trophic levels within a food chain. Primary consumer

Secondary consumer Tertiary consumer

Quaternary consumer Fifth level consumer

Sixth level consumer …and so on…

*Organisms can be more than one type of consumer depending on what all they eat.

Primary Consumer The 1st consumer in a food chain that

eats the producer Only gets 10% of the energy created by

the producer.

Secondary Consumer The second consumer in a food chain

that eats the primary consumer. Only gets 10% of the 10% of energy = 1%

Tertiary Consumer 3rd consumer that eats the secondary

consumer. Only gets 10% of the 1% of the energy

from the secondary consumer = 0.1%

Food Web A complex network of many

interconnected food chains and feeding relationships.

Most animals eat more than one kind of food in order to meet their energy needs therefore are part of more than one food chain.

Color code your food web Color code the arrows on your food web

according to the key below. Glue your food web into your journal

and illustrate the key as shown below.

Number 1-6 and Complete the following in your journal.1. List an organism that is a producer.

Cactus, mesquite tree, grasses

2. Name 2 secondary consumers. Toad, rat

3. Is the rattlesnake a secondary or tertiary consumer? It’s a secondary and a tertiary consumer

4. Would the praying mantis be considered a carnivore or a herbivore?

A carnivore because it only eats other animals

5. Where would you place bacteria and fungi in this web? Why? Anywhere, bacteria and fungi are decomposers so they break down

any decaying organic matter.

6. If the producers in this food web have 140,000 kilocalories of energy, how much would be available to the primary consumer?

14,000 (only 10%)

Part I

Introducing the Field of

Beans

Part 1: Introducing the Field of Beans1. Look at the picture of the organisms that

you were given and glue it into your journal.

2. Read the descriptions of each organism on the class copy of “Animal Descriptions.

3. Using each animal’s description, accurately construct a food web by connecting the organisms on your picture using arrows showing how energy is transferred from one organism another.

Color Code your arrows on your food web using the key below

Part II

Sampling the Field of Beans

Population Sampling The process of taking a small group of

organisms that is representative of the entire population. The sample must have sufficient size to warrant statistical analysis.

This is how biologists estimate the population of different species in an area.

Part II: Sampling The Field of Beans

Random Sampling A method of population

sampling where sample sites are

selected at random to be

counted.*Each square represents a

sample size in an area that is 100 square miles

Part II: Radom Sampling the Field of Beans To the right is an area

of land. Rather than send 100 students out to count the organisms in the entire area, the teacher sent 5 to randomly sample the population. Students counted the organisms in the labeled sections.

Pre-Lab questions Complete the following in your journal.

1. Determine and record the size of the population using random sampling by counting the organisms in the bolded areas.

Each dot represents an organism

Pre-Lab Question #1 There are 9

organisms in the 5 sample sites.

9/5 = 1.8 organisms

Sample site = 1/36 (there are 36 blocks in the entire area)

1.8 x 36 = 64.8 organisms total

Pre-Lab Question #2 Compare your

estimation to the actual size of the population. Count everyone of the dots

in the entire area.

There are a total of 40 organisms. Our estimation was more than the actual #.

Pre-Lab Question #3 List at least 2 ways to

improve this method of sampling.

Increase the number of samples taken.

Increase the area covered by each sample site.

Spread the samples out across the site more evenly.

Pre-Lab Question #4 In a forest that measures 6

miles by 6 miles, a sample was taken to count the number of red oak trees in the forest. The number of trees counted in the grid is shown. The grids where the survey was taken were chosen randomly. Determine how many red oak tress are in this forest using the random sampling technique.

Pre-Lab Question #4 con’t 35 trees counting in 5 sample sites

Divide 35 by 5 = 7

There are 36 total sample sites Multiple 7 x the 36 total sites = 252

, = 7

7 x 36 = 252 red oak trees

Pre-AP: Field of Beans Sampling Lab Activity Materials

Beans Organism Identification cards 2 Dice Butcher paper divided into 12 plots Calculator Data Table 1

Procedures1. Your “Field of Beans” is divided into 12 sections.2. Roll 1 di and then identify and count the number of

organisms in that sample site and record in Data table 1

3. Roll 1 di 2 more times and record the numbers in the data table. If you get the same number as before, roll again. (do not recount the same sample site)

4. Roll 2 dice 3 times identifying and recording in data table 1.

Use the Organism Identification Cards to identify what organism each bean represents.

Data Table 1 Sample site (Roll only 1 Di) (Roll 2 Dice) Total

Number x100 Organism

1 2 3 4 5 6 Avg.

Ants * Bobcat Burrowing owl Cacti and century plants ** Coyote Gopher tortoise Grasshoppers *** N. grasshopper mouse Ord’s kangaroo rat Praying mantis Red tailed hawk Southern plains woodrat Texas toad Texas horned lizard Western rattlesnake *1 ant bean = 250 ants ** 1 plant bean = 200 plants *** 1 grasshopper bean = 100 grasshoppers

NOTE!!!*1 ant bean = 250 ants

** 1 plant bean = 200 plants

***1 grasshopper bean = 100 grasshoppers

Procedures Con’t Once you have counted and recorded all of the

organisms in each of the sample sites, find the AVERAGES (mean) of each organism and record it in Data Table 1 under “Avg”. (Add up the total number organism found in each sample site and divide by 6)

Do not round your averages Multiple your averages for each organism by 12

and record that in Data Table 1 under “Total Number x 12” Round this number to the nearest whole number

Part III

Constructing the pyramids

Part III – Constructing the Pyramids Energy Pyramids

Pyramid of Numbers vs. Pyramid of Biomass Pyramid of

numbers simply shows the total number of organisms in each population.

Pyramid of biomass is based on the total amount of biomass (living matter) of each population.

Biomass The total mass of a specific organism in

a given area or ecosystem. Mass of living things in an area

Calculating Biomass Look at Data Table 2 and multiply the

“Total Number” of each organism with the Mass given on the table.

Biomass = Number in population x Average mass of organism

Record the Biomass of each organism in Data Table 2 under “Biomass”

Complete the following in your science journal

#1. Draw a food chain and energy pyramid with the organisms below. You may draw a triangular pyramid or a pyramid composed of rectangles. Identify the producer, and level of each consumer.

Blue birdCaterpillarSparrow HawkOak Tree

Practice Uses the data table below to create a

pyramid of numbers and pyramid of biomass

Your food chain should look like this

Oak Tree Caterpillar Blue Bird Sparrow Hawk

Your energy pyramid should look like either one of these.

Oak Tree

Caterpillar

Blue bird

Hawk

Hawk

Blue bird

Caterpillar

Oak Tree

Your pyramid of numbers should look something like this.

1

20

5000

1

Your pyramid of biomass should look like this.

1200g

900,000g

10,000g

12,000g

Part III – Constructing the Pyramids Materials:

Data Table 2 Highlighter Calculator

Procedures: Record the total # of organisms that you

calculated in Date Table 1 into Data Table 2 under the column labeled “Total Number”.

Food Chain:

Pyra

mid

of

En

erg

yP

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Nu

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Pyra

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Bio

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Set up your next

notebook page as shown.

Procedures Con’t Using Field of Beans food web, locate a food

chain that consists of at least 5 trophic levels. You must have had them in your Data table 1!

Draw the food chain in your journal. Using your food chain, your are going to

construct 3 pyramids. Using a highlighter, highlight the rows that

contain the organisms that you selected in your food chain on Data Table 2.

1. Pyramid of Energy

100%

10%

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0.1%

0.01%

90%

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Copy everything provided on this page.

Label each section with the appropriate category: Producer and Primary through Quaternary consumer

Write the name of the organism from your food chain in each corresponding section.

2. Pyramid of Numbers

5, 842, 000

708, 000

354, 000

10

10

Construct your pyramid of numbers by starting with the bottom layer, in this case, the producers in your food chain. Draw the bottom layer of the pyramid as a horizontal rectangle. Continue to draw the remaining layers proportional to the previous layer. As you can see below, the rectangles DO NOT have to be smaller

than the row below. As you are drawing your pyramid of numbers…

Using your data in Data Table 2, write the total number of organisms in each box of the pyramid as shown below

Write the name of the organism (from the food chain) next to its corresponding part of the pyramid.

3. Pyramid of Biomass

Use your data from Data Table 2, start constructing this pyramid with the bottom rectangular layer. Continue to draw the remaining layers proportional to the previous layer. Remember to keep the layers in order of the food

chain regardless of the size of the layer.

Example Data

Food Chain 5 Trophic Levels

1. Cacti2. Grasshopper3. Grasshopper mouse4. Owl5. Snake

Pyramid of NumbersTotal Numbers:

0 – rattlesnakes

20 – burrowing owls

30 – grasshopper mice

8000 – grasshoppers

22,000 - cacti, trees, and plants

Pyramid of Biomass

Conclusion Questions

Answer the conclusion questions in your

journal using COMPLETE Sentences and use proper academic

vocabulary

Vocab: Biomass Sustainability Competition Predation Biodiversity Populations Migration

Adaptation Death/extinction Consumers (1st, 2nd,

3rd, 4th) Producers Biotic and abiotic

resources Energy flow/pyramid Food chain/web

1. Would you and partners agree that your

population sampling was an accurate reflection of your “field of beans”? Explain why or why not.

Based on your Sampling, does your “field of beans” have a high or low diversity? Justify why you believe it’s high or low.

2. Compare and contrast your pyramid of

numbers and pyramid of biomass. How are they alike/different? Why is it important to look at both

before making a conclusion about the sustainability of the area?

What makes it sustainable?

3. Which organism(s) in the food web has

the most numerous sources of food? List the organism(s) and food sources.

Why is it important for them to have multiple food sources?

4. List any organism that has a single food

source, and make a prediction as to what would happen if the food source for the organism you listed is removed.

5. Describe how a natural disaster, like a

drought or grass fire, would affect an herbivore, carnivore, and an omnivore in this biome.

5. Explain why an ecosystem with high

biodiversity will have better recovery/ sustainability after a natural disaster that an ecosystem with low biodiversity.