Montana State University

Insect Mouth Parts

Subject: Life Science, Insects, Insect Morphology
Classtime: 2- 50 minute class periods
Grade Level: 2-3

Integration & Introduction:

This is a series of classroom activities that teach students about the diversity of structure within the insect world and how those structures affect insect behavior. Students observe, compare, and describe – both verbally and in writing – how different insects are able to eat different types of foods and thus live in diverse environments where those foods are found. Students learn that closer inspection of small living things like insects reveals significant clues to diet and habitat. Having students draw insect structures encourages the visual arts, as well as closer observation of the natural world outside the classroom. Writing individual stories and journal entries strengthens student ability to develop and communicate science concepts. A legend from the Ojibwe people about how a fly defeated a fearsome moose shows that even the very small among living things can have a great effect on the surrounding world.

Learner Outcomes:

Students should be able to:
  • Observe and compare the structure of different types of insects, both the entire insect body and closer views of insect mouth parts.
  • Realize that body structures can affect the behavior, diet, and habitat of living things.
  • Recognize that native cultures not only honor and respect magnificent creatures such as the horse and the bison, but also the small ones like the fly.

Content Standards:

  • Science as Inquiry Content Standard A: Abilities to do scientific inquiry
  • Life Science Content Standard C: The characteristics of organisms
  • Life Science Content Standard C: Life cycles of organisms

Problem/Purpose:

The purpose of this activity is to teach students about structural diversity among different types of insects, as illustrated by the shapes and uses of insect mouth parts. Students will observe and describe mouth-part structures from a number of insects and learn that structure can influence how the insects use their mouths. Students also will learn from American Indian legend that insects, though usually very small, can greatly affect much larger animals.

Background:

The Ojibwe people originally lived in what is now Canada. Eventually many lived in the forests around two of the Great Lakes, Huron and Superior. There they hunted and fished and grew their own crops. Today many live in the Upper Midwest area of the United States, both off and on reservations.

Insects are in the kingdom Animalia and in the phylum Arthropoda, that is, the animals with jointed legs and external skeletons. Class Insecta contains an unknown number of insect types, but scientists know that there are more kinds of insects than all other kinds of animals put together. All adult insects have three pair of legs and three principal body segments or parts – head, thorax, and abdomen. As they grow and mature during their respective life cycles, insects change physical form in a process called metamorphosis. Insects are highly successful animals because, as a group, they have adaptations that allow them to live in every type of environment. They can live above ground, underground, in the water; they can fly, carve tunnels in wood and dirt, and swim. Many insects affect human societies, either through beneficial ways like bees making honey or through destructive ways like termites destroying houses or beetles eating crops.

Insects live throughout our world and are familiar to all students. One of the reasons that insects are able to live in so many environments is the vast diversity of insect morphology or body structures. These include mouth parts that insects use to eat and drink, whether they chew, suck, or absorb their foods. Mouth parts are also used by insects to bite humans and other animals.

Materials/Technology:

  • Insect structures activity – hand-held magnifying glass, white drawing paper, colored pencils, insect specimens (flies, bees, grasshoppers, caterpillars, etc.)
  • Eating tools activity – M&Ms, individual boxes of juice, pudding cups, fruit roll-ups, fruit gelatin cups, applesauce, gummy insects (for a snack); chop sticks, drinking straws, tweezers, pieces of bread, small coffee stirrer
  • Journals and pencils

Safety, Handling, Disposal:

Remind students not to touch the fly bodies used in the classroom, as flies can carry germs (i.e., microorganisms like bacteria and viruses) that might make people sick. Place insects for observation in small paper cups or in other containers that allow easy viewing of insects without handling. Also caution students that if they observe living insects outside the classroom, many insects can bite.

Vocabulary:

  1. Head - Insects feeding and sensory center
  2. Thorax - Middle section of an insect
  3. Abdomen - group of segments containing the digestive and reproductive organs
  4. Metamorphosis - insect going through different froms from egg to larva to adult
  5. Life Cycle - The process of an insect going through all stages of its life

Procedure:

  1. Ask students to pretend that they are a fly in their house or yards. Have each student write a story about what they would do and where they would go as a fly. Stories will be read aloud in class.
  2. Read the Ojibwe legend about how the fly saved the river and then ask students to discuss the story:

    Many, many years ago when the world was new, there was a beautiful river. Fish in great numbers lived in this river and its water was so pure and sweet that all the animals came there to drink. A giant moose heard about the river and he also came there to drink. But he was so big and he drank so much that soon the water began to sink lower and lower.

    The beavers were worried. The water around their lodges was disappearing. Soon their homes would be destroyed. The muskrats were worried too. What would they do if the water vanished? How could they live? The fish were very worried. The other animals could live on land if the water dried up, but they could not. All the animals tried to think of a way to drive the moose from the river, but he was so big that they were too afraid to even try. Even the bear was afraid of him.

    At last the fly said he would try to drive away the moose. All the animals laughed and jeered. How could a tiny fly frighten a giant moose? The fly said nothing, but that day, as soon as the moose appeared at the river, he went into action. He landed on the moose’s foreleg and bit sharply. The moose stamped his foot hard and each time he stamped, the ground sank and the water rushed to fill the hole. Then the fly jumped all over the moose, biting and biting and biting until the moose was in a frenzy. He ran wildly back and forth on the banks of the river, shaking his head, stamping his feet, snorting and blowing. But he could not get rid of that pesky fly.

    At last the moose ran from the river and did not come back. The fly was very proud of his achievement and boasted to the other animals, “Even the small can fight the strong if they use their brains to think!”

  3. Give each student a magnifying glass, drawing paper, and colored pencils. Have them draw the different insects provided in the classroom, including fly, butterfly, mosquito, and caterpillar, ant or grasshopper. They will draw two pictures for each insect – one of the whole insect, the second of the insect’s mouthparts. Students will hang drawings around the classroom or in the hallway and discuss in class the structural differences among the various insects.
  4. Give students science journals to record their experiments and observations about how different insects collect food differently:
    • Ask students to pretend they are an insect that hasn’t had anything to eat all day. How do you think you would eat your favorite foods if you found a table full of human food?
    • Explain to students that not all insects eat food in the same way. Use the example of how human babies and adults do not eat food the same way. Why is that true?
    • Tell students that not only do insects eat in different ways, they also eat different types of food. Some insects chew food, so they eat things like grass and leaves. Some eat soft food like vomit and decaying garbage. Others suck in their food and live on liquids like blood, water, and juice.
    • Place the food items on a table: M&Ms, individual boxes of juice, pudding cups, fruit roll-ups, fruit gelatin cups, applesauce, gummy insects (for a snack). Also arrange on the table the tools to use as different types of mouth parts: chop sticks, drinking straws, tweezers, pieces of bread, small coffee stirrers.
    • Show students the eating tools available and allow them to choose which insect they would like to be:
      • Chop Sticks – caterpillars, grasshoppers, ants
      • Small coffee stirrer – mosquito
      • Straw – bees and butterflies
      • Bread – fly
    • Ask students to form a hypothesis about which food they will be able to eat with their utensils.
    • Give the students the opportunity to eat the various food items with the utensils assigned to them.
    • Discuss as a class the problems found while trying to eat different foods with different tools (mouth parts).
    • Make certain that students have recorded their various observations throughout this experiment in their science journals.

Conclusions:

Example:
The type of mouth parts an insect has determines how the insect eats and therefore what type of foods the insect is able to consume.

Assessments:

Student drawings of insect structures

Participation in class/group discussions

Science journal entries

Student stories about being a fly

Follow-up quiz on student observations: Quiz Example:
  1. Draw a picture of a butterfly. How does the butterfly eat its food?
  2. Draw a picture of a fly. How does a fly eat its food?
  3. Draw a picture of a mosquito. How does a mosquito eat its food?
  4. Draw a picture of a grasshopper. How does a grasshopper eat its food?


Student research on what foods different insects eat and why (Internet and/or books)

Extensions:

Note the differences among insects found outside the classroom, especially their wide variety of structures and the different foods they eat.

Observe the different places outside and indoors where flies like to live. Why do they live in those particular places? Ask students to discuss why specific types of insects are found in specific environments (e.g., bees in gardens or hayfields, flies near garbage dumps or picnic tables).

Discuss how human mouth parts are able to eat so many different types of food. Why is this possible?

How do different insects affect humans, that is, the day-to-day lives of the students? Some insects are considered “bad” insects, others “good insects.” Why? How do mouth parts of insects affect how those insects interact with humans?

References/Resources:

  • Insect Anatomy - http://www.earthlife.net/insects/anat-head.html
  • Insect Identification - http://fciig.ifas.ufl.edu/insik.htm
  • Free Dictionary - http://encyclopedia2.thefreedictionary.com/
  • Insect anatomy - http://www.livescience.com/insects/
  • Insect life cycle - http://www.kidfish.bc.ca/insects.htm#cycle1
Author: Kelly Concho
Campus ToolsStudent E-MailDesire2LearnMy InfoMy MSU PortalMy Passwords