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Teaching Guide
Guide Title
Growing Prairie
Indentifying Species
Follow Your Nose
Quiz
Image of Ladybug

As you saw in Raven's World, conservationists like Peter Raven face many challenges in their fight to maintain biodiversity. In a rapidly changing and industrializing world, these scientists are working to insure that the richness of species survives for future generations. Their work is important, because extinction not only reduces the number of species here on Earth, it also compromises the stability of our delicate ecosystem in which all species are interdependent.
note to educators

 

Take a look at these beautifully diverse insects and spiders. These images are printed on the United States postal stamp Classic Collection. There are twenty different species presented in this stamp collection - a great offering for the biodiversity activity below.These images can also be found online:

OBJECTIVE
This activity page will offer:

  • understanding of human hand structure and function
  • appreciation of the complexity and range of hand motions
  • exploration in which to apply critical observation skills

PART 1 - GROUPING

MATERIALS

  • print out of Insect & Spider stamp block page
  • scissors

PROCEDURE

  1. Work with a partner to examine a printout of this page of insects and spiders.
  2. Use your scissors to carefully cut out and separate each of the twenty animals.
  3. Divide these images into two groups, A & B. Write down the characteristic upon which an animal is placed into either group.
  4. Select a different characteristic to divide group A into two sub-groups. Write down this characteristic. Pick another characteristic (or the same one you used for A) to divide group B into two sub-groups. Write down this characteristic.
  5. Continue dividing the groups using identified features until every insect or spider is sorted into its own unique category.

QUESTIONS

  1. What was the first characteristic you used to divide the group? Why did you pick this one?
  2. What characteristics did you use to continue dividing the groups up? Why?
  3. How many features did you need to separate all twenty organisms into their own distinct group?
  4. What class do and flies belong to?
  5. What class do spiders and ticks below to?

PART 2 - MAKE A KEY

  1. Both partners select any four of the insects and spiders.
  2. Divide them into two groups (each containing two animals), similar to what you did in the first part of this activity. Record the features that you selected to define your groups.
  3. Take a look below. This is a taxonomic key that can be used to distinguish between the black widow, yellow garden spider, monarch butterfly, and monarch caterpillar

    I
       Ia
    Animal has 4 pairs of legs
    go to II
       Ib
    Animal has 3 pairs of legs go to III


    II
       IIa
    Animal l has a hourglass marking black widow
       IIb
    Animal has light pattern on its abdomen yellow garden spider

    III
       IIIa
    Animal has bright orange wings monarch butterfly
       IIIb
    Animal has a long worm-like body monarch caterpillar

  1. Now create your own taxonomic key to distinguish between the four animals you selected and described in steps one and two.
  2. Trade your four stamps and your key with your partner and examine each other's work. Does the key work?


QUESTIONS

  1. How many characteristics are used to differentiate organisms in each step of this key?
  2. What are the two possible outcomes associated with each statement within a key?
  3. How many statement pairs are needed to distinguish between four species?
  4. Did your key work for your partner? If not, what might have been done to improve it?

EXTENSIONS

CHALLENGE

Working with a partner, create a large format key that differentiates between all of the invertebrates illustrated on the page of stamps. Paste the picture of each insect or spider along side of its name when it is identified in the key.

TRANSECT STUDY

Are you aware of the different types of animals and plants that live in your surroundings? What are the most common organisms? Which are the largest? Which ones are affected by seasonal changes? In order to best quantify and qualify the types of organisms that inhabit a specific area, scientists use a technique called a transect study. During this type of investigation, a representative region is examined for organisms. Within the bounds of the transect, species are collected, identified, and counted. The results of this small collection are then used to help make a "best guess" about the biodiversity of the entire region. One common type of transect uses a square frame (1 ft by 1 ft) to set the boundaries of the study. The frame is placed at given intervals along a transect route. The organisms that fall within the open frame are included in the study. With your instructor's approval, perform a transect study of a neighborhood field or school playing ground.

TRANSECTING THE LIMIT

Although a transect is a valuable tool in generating a list of representative species, it may have limited application in projecting species numbers for a given ecosystem. Due to the spotty and sometimes random scattering of organisms, the sample may be skewed. Think about it.
How would you design a sampling technique to insure that you have a fair census of species in a 1,000 square meter field. Assume that the field has similar characteristics throughout.
How many 1-square meter transects would you need to insure a representative sample that can be used to project realistic numbers?
How would you locate these samples?
How might the number of samples affect the reliability of your survey?
What characteristics set the "tradeoff" between too few and too many samples?

HOW DIVERSE ARE YOUR SURROUNDINGS?

As a class compile a list of the animals and plants that are found within a mile of your school. You may need to use field guides, local resources, taxonomic keys, and species lists to help identify these organisms. Once you've compiled your list, organize the species into the taxonomic groups you have studied in school. When the list is complete, have your instructor email it to us. We'll post your diversity list with the other lists we receive from schools around the world.

ARTFUL CONNECTION

Create a montage of images that illustrate the concept of biodiversity. You can collect these pictures from old magazines, print outs, or discarded books. In addition to this colorful display, create a separate key that identifies each organism. To produce the key, make a reduced outline drawing of your poster. Position the name of each organism over the appropriate outline.

NOTE: You can find examples of this type of identification scheme in field guides, natural history books, and selected ecosystem illustrations in issues of National Geographic.

WEB CONNECTION

Biodiversity and Biological Collections Web Server
This site has links to several areas of biodiversity and biological collections

Phylogeny Study
An interactive and friendly database on biodiversity that offers a rich library of species photos

Canada's Digital Collections Program
A virtual exhibit on the biodiversity of insects

Department of Entomology;Texas A&M University
Texas A&M lesson plans on biodiversity and more


Answers

The activities in this guide were contributed by Michael DiSpezio, a Massachusetts-based science writer and author of "Critical Thinking Puzzles" and "Awesome Experiments in Light & Sound" (Sterling Publishing Co., NY).

Academic Advisors for this Guide:
Corrine Lowen, Science Department, Wayland Public Schools, Wayland, MA
Suzanne Panico, Science Department, Fenway High School, Boston, MA
Anne E. Jones, Science Department, Wayland Middle School, Wayland, MA

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