In this unit, the students will explore some
basic ecological (energy transfer, predator-prey relations, abiotic-biotic
interactions, etc.) concepts using spiders. They model real scientific
processes while caring for and studying spiders both in the classroom
and in the field. At the end of this unit, students will be able to:
- define the predator-prey relationship.
- identify links in the food chain/web
and distinguish between producer, consumer (primary/secondary), and
- give examples of how predators and prey
put selective pressures on each other contributing to coevolution
in an arms race of which can catch and which can avoid being caught
- discuss regulation of numbers of prey
- describe ways in which all organisms
interact with the environment and with other organisms (abiotic and
- describe how an event which affects
one organism affects others, directly or indirectly.
- group organisms by how they obtain their
food (energy)-- for example, sit and wait, ambush, stalk, etc.
- explain how the science process and
experimentation is used to answer questions.
- identify plants as the base of all food
- outline the steps used in a mark and
recapture study to determine population numbers.
- identify the assumptions behind a mark
and recapture study and identify appropriate situations this would
be used for.
- apply concepts to new situations.
Find out what students already know about spiders.
Make a list on the board. Things they might
say: 8 legs, many eyes, poisonous, dangerous, black widows are dangerous,
there are big wolf spiders and tarantulas, make webs, eats bugs. Ask
students to write at least one question concerning spiders. Collect
and read through some of them. Do not offer answers to their questions.
Write the questions down on butcher paper or some other permanent record
to be referred to later by the students for ideas for their experiments.
Add to this list as questions and new ideas arise in class.
Be comfortable and relaxed in the presence of
spiders. Model appropriate handling of spiders and respect for living
organisms. Spiders really aren't as dangerous as most people believe.
Most are reluctant to bite--why should they waste good venom on something
too big to be eaten?! Still care and caution should be taken because
of possible allergic reactions to a spider's bite and venom. However,
spend some time to build student confidence. Let the students enjoy
a pet tarantula. Hold it to show off during class. If students want
to hold the tarantula have them come in during lunch or after school
when there is not so much excitement. Jumping spiders are easy to handle,
do not readily bite, and can be held in front of students to show off.
Show pictures or slides. Have fun!