Overview:

The Peppermint Beetle

Preparation Time 50 minutes
Activity Time 50 minutes
Grades K-3

In this activity students will be able to explore their sense of smell and discover why smell is important to insects.

Concept: Organisms adapt to changes in the environment according to the genetic and behavioral capacity of their species.

Skills: reasoning, discussing identifying relationships and patterns, concluding

Purpose:(objective)

Students will (1) describe various ways insects use their sense of smell, (2) explain why some insects use scent marking, and (3) identify the importance of the sense of smell in our daily lives.

K
Knowledge and Skills and Student Expectations
TEKS Common to all Scientific Principles
(3) Critical Thinking and Decision Making (a) make decisions using information
(4) Tools (a) use senses as tools of observation

Grade 1
Knowledge and Skills and Student Expectations
Systems
(9) Living Organisms-Basic Needs
(a) identify characteristics of organisms that allow basic needs to be met
(b) compare examples of how organisms depend on each other for basic needs

Grade 2
Knowledge and Skills and Student Expectations
Systems
(9) Living Organisms-Basic Needs
(b) compare examples of ways organisms depend on each other and their environments

Grade 3
Knowledge and Skills and Student Expectations
Systems

(8) Living Organisms Needs- food, water, light, air, waste disposal, environment
(d) describe how organisms modify environment to meet their needs
(9)Adaptations Increase Survival of Species
(a) observe and identify characteristics that allow survival
(b) analyze adaptive characteristics

Materials:

Small bottle of concentrated flavoring ( peppermint, cinnamon, wintergreen, etc.), Cotton balls, Ball of yarn, Flagging materials or rags to mark boundaries, Several baby food or small jars with lids, several organic liquids or substances with strong distinctive

WARNING: Read the label on all items before deliberately inhaling them. Many substances such as nail polish remover, white out, and rubber cement are harmful to inhale.

Getting Ready:

BACKGROUND: Taste and smell are chemically activated senses and are closely related , we are actually smelling much of what we think we are tasting. For a substance to be smelled and tasted, it must first be dissolved on the membrane of the olfactory area in the nasal passages. That's why a person whose nasal passages are blocked because of a cold cannot smell or taste food very well. The ability to respond to chemicals (smell or taste) is probably one of the earliest senses developed by organisms. It is especially important in the insect world. When foraging worker ants find food, they leave a scent trail for other ants. The ants touch their abdomens to the ground and secrete a substance that is detected only by their antennae. The better the food source, the more scent markings the ant will leave on the trail. If another animal accidently crosses the scent trail and breaks it, the ants become disoriented and confused. To define an area or territory, many animals/insects mark objects with scent from special glands. Scent-marking can be used for finding a mate or for establishing an area for family, shelter, and food supply. Animals/insects often defend their territory from intruders, especially members of the same species.

GETTING READY:In preparation, flag or mark boundaries in a wooded area and "scentmark" on the same line. Preferably, mark at least one tree per pair of students. Scent-mark the trees by moistening a cotton ball with peppermint oil ( or other aromatic flavoring) and rubbing it on the bark around the tree at the nose level of a student of average height. Mark the trees close to the time the students will do the activity because the peppermint oil will evaporate. Cut lengths of yarn long enough to be tied around the tree trunks. Provide several lenghts of yarn for each pair of students.

Motivate:

Tell the students about an insect called the peppermint beetle (name it after whatever scent you have chosen to use). The beetle has been discovered to live in the area and has recently visited the school ground. (The area where you have the activity set up.) This flying beetle is famous for the scent it occasionally marks on trunks of trees. Be creative with your story.

Activity:

1. Ask your students how their sense of smell is important to them. Did they ever have a cold and lose their sense of smell? How did it feel? Did it affect your sense of taste? Could your sense of smell save you from dangerous situations? (detect gas, smoke, rotten food) At this point you might want to have the students explore their sense of smell in more depth by doing the enrichment.

2. Next, ask students how different animals rely on their sense of smell. Do these animals rely on smell more or less than people do? What purpose does smell serve for these animals? (It helps them find food, detect danger, find a mate, and identify another animal's territory.) You might want to allow students tims to go to the library and research how animals/insects that interest them use their sense of smell.

3. Now that they have more background about animals/insects and smells they will work in teams to find the trees that the beetle has marked.

4. At the activity site, divide the group into pairs, and give each pair several lenghts of yarn. ( If your site has relatively few trees, use larger teams so that you have more trees than teams.) Tell each team to use their noses to find trees that the beetle visited. If they find a tree that both team members agree is scent-marked, they should tie the yarn around the tree. Teams should continue searching for scent-marked trees; they need not check trees that have already been identified.

5. When all the trees have been found, have the students walk the scent trail left by the beetle. Ask the students to consider why the beetle marked those trees. Could it be to attract a mate, or define a territory? Where might the beetle's trail lead? To a food source? Its home? Or nowhere in particular?

Going Further (ENRICHMENT): Make "mystery jars" to test how well students can recognize smells. Collect baby food jars or other small containers (film canisters are a safe choice for very young students.) Put a wad of cotton in each jar. Collect liquids with strong distinctive smells such as perfume, vanilla, vinegar, or food flavorings. Pour a few drops of each liquid aromatic into different jars or place solid aromatic substances such as cloves, lemon peels, or garlic into film canisters or jars covered with paper. Poke a hole in the lid of each jar and screw lids down. Label the jars A,B,C, etc. Let the students smell each jar, and have them write down what they think each smell is and where they've smelled it before. You can also try putting the same scent in two different jars and see if the students can find and pair with the same scent. Afterward, ask the students if certain smells triggered certain memories.

Closure:Review with the students all that was done in the activity and ask questions to check for understanding.

Assessment:Ask the students to name animals/insects that also use scent to mark objects. How do they do this? (urine, special scent glands) Why might they do this? (To identify themselves to other members of their species, to attract a mate, to mark their territory.) Do animals/insects publicize their territories using methods other than scent-marking? What are they trying to protect in marking territory? (Food, water, shelter, family.) Do people mark their territory? ( Fences, hedges, signs.) Ask the students to think of ways that people use their sense of smell. Ask them if they could use their sense of smell to find food. For example, could you find a pizza in the kitchen with the lights out? Why is the smell of food important?

Connections: To put into social studies you could have the students plot the trees on a piece of paper making a map of the ground. Then they could plot the path of the beetle on their map incorporating directions of North, South, East and West correctly.

Lesson adapted fom Project Learning Tree Environmental Education Activity Guide

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