## Escape! Survival of the Fittest Grasshopper

### Lois WalshBay District Schools

#### Description

Lab Activity: Student teams design a paperclip grasshopper and measure its ability to survive a prey by either jumping high, far, or with a distracting behavior. Students relate the ability to survive to the changing attack of predators.

#### Objectives

Adds, subtracts, multiplies, and divides real numbers, including square roots and exponents using appropriate methods of computing (mental mathematics, paper-and-pencil, calculator).

Selects and uses direct (measured) or indirect (not measured) methods of measurement as appropriate.

The student understands the mechanisms of change (e.g., mutation and natural selection) that lead to adaptations in a species and their ability to survive naturally in changing conditions and to increase species diversity.

#### Materials

- Paper clips
- Lab Directions & Data table
- Metric rulers
- Meter sticks
- Calculators
- String, optional

#### Preparations

2- Prepare data sheets and directions
3- Gather materials
4- Make model for demonstration(optional)

#### Procedures

Since the benchmark is so broad this lab activity is an intermediate step addressing the part of the standard: understanding a species' ability to survive naturally in changing conditions.

(A) Set the Stage:
Remind students of the predator-prey relationship. Emphasize that survival is based on fight or flight.
Brainstorm with students for solutions to this scenario: If a bird spotted a grasshopper for dinner and was about to capture it, how might the grasshopper survive? Allow for students' responses. Give them another scenario with a change of conditions such as the predator is a snake (or a frog or a human). Allow for students' responses.
Conclude by reminding students that in studying such a relationship the variables should be limited or controlled. In the lab students look at three of the possible survival techniques of flight:
-jump high
-jump far
-jump with a distracting or unexpected behavior (to confuse the predator.)

(B) Overview of the lab:
1. Divide students into groups of two to four. Each group member creates a grasshopper out of a paperclip that can escape by jumping high, far, or with a distracting behavior. Students may need to experiment with their designs, practice jumping and then test them.(The teacher may show a model grasshopper design or the teacher may allow the students to discover it themselves.) The main idea is to use the paperclip like a spring by compresing it with your finger against the table top and releasing it; this will make it 'jump'.
2. Students challenge the other members of the group by measuring and recording their grasshopper's jumping ability. Students should use the ruler and meterstick and may have to practice observing the height of the jump. Students may need the suggestion when measuring distance to mark the jump and then measure it. Students may need guidance in describing the distracting behavior of the grasshoppers.
3. Each grasshopper should jump three times and the averages calculated. The best grasshopper of each survival technique will be determined and recorded in the data.

(C) Conduct the Experiment:
Hand out lab directions and data sheet. Assign students to groups and work areas. Students collect materials and report to assigned area. They conduct the experiment, cleanup, and return materials. They return to their seats and complete their lab reports.

(Note to Teacher)
In design student can pull apart or widen the paperclip (too many bends and the paperclip will break). Some will rebend it making their own design and can even wrap it around a pencil to make a spring. Students need to practice in making it jump. Some hints in this area: - try bending at greater or lesser angle and see how it jumps. - try making it jump with the smaller curve on the table top and then the larger curve on the table top. The student element in making it jump is the biggest factor. Pushing down quickly on the edge is the most common way. It should spring and flip on release. Some students will try hitting or thumping the paperclip. They may need help or reminders in calculating averages with the calculator, in using the decimal place, and in writing the unit of measurement(cm). Peer teaching is great here!

(D) After/ Wrap it Up
After students have their results and put up equipment they will need to reflect on the activity and answer the questions on the lab report. The questions would include 1)identifying ways a prey can survive a predator,2) analyzing the averages and determining the best survivors, and 3) applying the three survival skills to a given condition and determining the effect. A class discusssion based on the questions, and conclusion reached in the lab may follow before or after lab reports are graded and returned. The discussion can also include the advantages and disadvantages to both predator and prey of each survival skill.

#### Assessments

Assess students informally while working and formally from the lab report.

- have a grasshopper that can jump
- list 5 ways a prey can survival
- have a summary statement of a prey's survival ability
- have cause and effect of prey survival to conditions
- use meterstick appropriately; horizonally for distance and vertically for height
- use and record centimeters to 10th place
- use calculator properly( in proper sequence)
- have correct calculated answers for average

Note: Circulate and formatively assess students as they use the technology tools (calculators). Provide assistance for students who are experiencing difficulty and monitor accordingly.

#### Attached Files

1 page Student Lab worksheet     File Extension: pdf