LIMITING FACTORS CHALLENGE - American Heart Association

LIMITING FACTORS CHALLENGE
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Description: Students will compete to collect the limiting factors they need to survive while avoiding predators
and disease.
Learning Objectives:
• Students will learn the effect of limiting factors on population sizes.
• Students will learn the effect of predator-to-prey ratios on population sizes.
• Students will learn the effect of disease on population sizes.
Activity Time: Day 1 – 60 minutes; Day 2 – 20 minutes
Materials:
Directions:
Day 1:
• 10 Limiting Factor Cards (five food and five air) per student (see attached)
• Colored armband (one per every 10 students)
• A different colored armband (1)
• Four hula hoops
• Six cones
• Whistle
• Open space/gymnasium
Set up:
• Prepare the playing field by designating one end of the field as the starting side,
setting up two cones to mark the starting line. Create a rectangular area
out of the four remaining cones on the other end of the field. Place the
four hula hoops throughout the field. Place all of the limiting factor cards
on the ground in the rectangular area at the end of the field.
Activity:
• Begin by discussing the effect of limiting factors on populations.
Emphasize the following:
– When there are enough limiting factors (air, food and space)
in an environment for all the organisms living there,
population sizes stay steady.
– When limiting factors are depleted, populations die out.
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LIMITING FACTORS CHALLENGE
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– When the ratio of predators to prey in an environment increases, the prey population declines
more quickly. Disease is a natural way for population sizes to stay in check.
– If a population is not reproducing, depleted limiting factors, increased predator-to-prey ratios,
and disease will eventually wipe out the population.
Select students to be predators (about one predator for every 10 students is needed). Give them a colored
armband to wear. Assign one student to be “disease.” Give him or her the other colored armband. All other
students will be prey.
• The goal of the game is for every prey to start at the starting line and run across the field to get five
food cards and bring them back to the starting line and then get five air cards and bring them back
to the starting line. (The students must make two trips from the starting line to the rectangular area
and back.) They may grab only one type of card at a time (i.e., air or food), but they may grab more
than one of that type of card at a time.
• If the prey are tagged by a predator or disease, they are out.
• If the prey are about to get tagged by a predator or disease, but they are near a hula hoop, prey
may step inside the circle to get 10 seconds of safe time. If a prey is in the hula hoop for more than
10 seconds, he or she is out. The rectangle containing the limiting factor cards is also a safe zone,
where prey cannot be tagged.
• After five to 10 minutes, depending on the kids’ energy levels, blow the whistle to end the round.
Take a count to see how many prey have made it back to the starting line with five food cards and
then five air cards without being tagged by a predator or disease. They have survived to make it to
the next round. Students who did not survive will be named judges, helping you enforce the rules.
• Take away two food and two air cards for every prey that originally began the game. The rest of the
cards go back into the rectangular area at the ending line.
• Play will continue with the prey who survived the first round. This round will be more
difficult because there will not be enough limiting factors for everyone.
As before, prey who get tagged by predators or disease will be out. At the
end of the round, take a final count of prey who have survived by getting
back to the starting line with five food cards and then five air cards.
• For the final round, remove all but one hula hoop from the field,
and take away one more food and one more air card for every prey
that originally began the game. Play resumes with prey that have
survived the first two rounds. End the round when you have
10 minutes of class time left.
• Conduct a quick discussion of what happened during
the game, pointing out what happened to the prey when
the limiting factors decreased.
The National Football League and the American Heart Association are proud to work together to produce What Moves U.
www.WHATMOVESU.com/teacher

Day 2:
• During class, discuss the science behind the activity. Discuss how what happened during
the activity shows how limiting factors control a population; if a population gets too big,
the environment naturally decreases that population. Point out that when the ratio of
predators to prey in an environment increases (as more students dropped out of the game),
the prey population declines more quickly. Disease is also a natural way for population
sizes to stay in check.
Extend the Activity: Have students journal what they learned through this activity.
Modification: Allow for shorter playing time and complete the activity and discussion in one day.
Note: Could be team taught with physical education teacher.
Submitted by Maria Boulmetis, Flat River Middle School, Coventry, Rhode Island
Correlation to National Curriculum Standards:
Correlation to National Curriculum Standards:
Content Standard B:
• Structure and function of living things
• Populations and ecosystems
Content Standard F:
• Populations, resources and environments
From NSES http://newton.nap.edu/html/nses/6d.html#csa58
LIMITING FACTORS CHALLENGE
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The National Football League and the American Heart Association are proud to work together to produce What Moves U.
www.WHATMOVESU.com/teacher

LIMITING FACTORS CHALLENGE
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FOOD
FOOD
FOOD
FOOD
FOOD
AIR
AIR
AIR
AIR
AIR
The National Football League and the American Heart Association are proud to work together to produce What Moves U.
www.WHATMOVESU.com/teacher