Dragon Evolution: A Kinesthetic Way to Model Allele Frequency Changes
One of the challenges I faced in teaching evolution to SBI3U was making an abstract concept something
the students could grasp. Evolution is a subject fraught with misconceptions and can be a very hard process to
imagine. Like all of science, there is a particular language that surrounds this topic and was important for my
students to understand. In order to make this a more accessible area of study, I developed a kinesthetic activity
to demonstrate how natural selection can act on a species and affects allele frequency. This activity was
developed as a follow-up activity to a wonderful Dragon Genetics Lab developed by Dr. Pamela Esprivalo Harrel
that can be found at: http://www.cpet.ufl.edu/wp-content/uploads/2013/03/Dragon-Genetics-Lab-Principlesof-Mendelian-Genetics.pdf. The dragon genetics lab is a great consolidation activity that I used at the end of the
genetics unit. My students loved their dragons so much that we decided to bring them along into our
exploration of evolution.
Teacher’s Notes
Basic Understanding:
Evolution is a change in heritable information passed on through generations. It is important for students to
realize that evolution happens at the level of a population rather than the individual and that a variety of
selective factors can influence evolutionary change, such as natural selection, kin selection, and artificial
selection.
Supplies:
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A copy of the alleles printed and cut out (2 for each student plus extras)
Plastic forks
Plastic spoons
Paper cups (or ½ a petri dish)
Dragon baby (with a hole in the mouth cut out)
Lentils (used as dragon food)
Construction paper (same and different colours from the lentils)
Clock or timer
Chopsticks
Cooked spaghetti
References:
Dr. Pamela Esprivalo Harrell, University of North Texas, developed an earlier version of "Dragon Genetics" which
is described in the January 1997 issue of Science Scope, 20:4, 33-37. Copyright 2005, Bob Farber, Central High
School, Philadelphia, PA
http://www.cpet.ufl.edu/wp-content/uploads/2013/03/Dragon-Genetics-Lab-Principles-of-MendelianGenetics.pdf
Baby Dragon Drawing drawn by Jonas Nelson http: //www.elfwood.com/~nelson/Baby-dragon.3078408.html
Story:
Baby dragons need to be fed by their parents until they are old enough to catch their own food. Their
prey (Lentils) can be camouflaged or found in the open (based on the colour of the construction paper). Having
fangs makes it easier for dragons to catch their food. This is a recessive trait, so dragons with the genotype ff
will be given a plastic spoon and those with Ff or FF will have a plastic fork. Without using any other implements
(hands, scooping, etc), you must catch your baby dragon enough prey to keep it growing until it reaches
adulthood and can reproduce. To keep your baby dragon alive, it needs to be fed at least 50 lentils. You will
have 1 minute to catch the prey and feed it to your baby. Good luck.
Classroom set up:
1. Each student will be given at random, 2 alleles (either f, F) and will have to determine their phenotype
and collect an appropriate implement to catch their prey.
2. Start a chart on the board outlining the allele frequencies.
3. In groups of 2-4, place a pile of lentils on the construction paper (taping it down helps prevent cheating).
Have the students balance their paper dragon baby over a paper cup (or ½ a petri dish) and set a timer
for 1 minute. The students will have to compete for resources and need to feed their dragon baby at
least 50 lentils to survive. They can try to support as many as 5 dragon babies/ generation. Note: if you
are feeding more than one baby, assume they are genetically identical.
4. At the end of round one, find out how many dragon babies survived and write Generation 1 allele
frequencies on the board.
5. The students will then be challenged to find a mate; they give this partner one of their alleles at random
and find out what their new phenotype is. Explain that they are now representing generation 2.
6. Repeat steps 3-5.
7. This can be done for as many generations as you have time for. Keep track of the number of babies that
survive and the allele frequencies.
8. If the parent is not able to feed their baby enough lentils, their babies don’t make it to adulthood and
they stop playing.
Extensions:
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Adding in ideas such as kin selection (if a student chooses to feed another student’s dragon and
more than one baby survives because of kin selection you can keep playing)
Increasing competition (fewer lentils or more players at each station)
Introduction of mutations; these can be positive (two spoons), negative (you go blind), or
neutral (you have webbed feet and have to sit with your heels together)
Change the prey to cooked spaghetti and watch what happens to the allele frequencies
At the end of the lab, encourage student discussion based on the questions on the lab sheet and have
them graph the allele frequencies based on class data.
Discussion topics: Dwarfism is the result of a dominant allele; why is this allele not more frequent in our
species?
Alleles
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
f
F*
F*
F*
Webbed
Feet
Blind
F*
f2
f2
f2
f2
Legend:
FF or Ff = No Fangs, Dominant (grab a fork) F*F, F*f = No Fangs, Mutation Dominant (grab a chopstick)
ff = fangs, recessive (grab a spoon),
ff2 = fangs, mutation, recessive (2 spoons)
Webbed feet F, Webbed f = Dominant,
Blind = Dominant, Keep eyes closed and use whatever
keep heels together , use appropriate utensil
utensils the F or f alleles dictate
Dragon Babies –Use an exactoknife to cut out their mouths
Student Sheet: Dragon Evolution
Dragons are evolving as we speak. This lab will help us determine how allele frequencies can change
because of natural selection. Having fangs is a recessive trait in dragons. Those dragons with fangs tend to
have an easier time hunting the prey available in our local dragon grounds. Your goal as a dragon is to pass
on your genetic material to the next generation. You do this by feeding your babies until they are strong
enough to hunt on their own and have their own little dragons. Your goal as a dragon parent is to feed your
babies and get them to the next generation.
1. Collect your materials: a dragon baby, dragon baby “stomach” (1/2 a petri dish), and a genotype.
2. Determine your phenotype and collect the appropriate “utensil”.
3. Station yourself at a hunting ground; remember, you can’t use your hands, you can only use the end
of your hunting apparatus to collect the food and feed your baby.
4. You will have a set amount of time to collect food and feed your baby dragon.
5. Each baby needs at least 50 lentils to keep it alive – if you don’t keep at least one baby alive, you
have not passed on your genetic material and you are no longer part of the evolution game.
6. Note how many babies of each genotype survived to adulthood and calculate the allele frequency.
7. If your baby survived to adulthood, your dragon can look for a mate, assume it has the same
genotype as you do. Find another dragon that has survived in the classroom and randomly select
one allele from each partner. After combing alleles, determine what your phenotype will be and
repeat steps 2-6.
8. For extra success, if you are confident, try to have more than one dragon baby (up to 5 at a time),
see if you can keep them all alive! Note: If you feed multiples, note that they are genetically
identical
9. After a few generations, look at the allele ratio in the class and determine the effect of spontaneous
mutations on dragon survival.
Legend:
FF or Ff = No Fangs, Dominant (grab a fork)
F*F, F*f = No Fangs, Mutation Dominant (grab a chopstick)
ff = fangs, recessive (grab a spoon)
ff2 = fangs, mutation, recessive (2 spoons)
Webbed feet F, Webbed f = Dominant, keep heels together , use appropriate utensil based on F alleles
Blind = Dominant, keep eyes closed and use appropriate utensil based on F alleles
Data Collection
Name:
What is your Genotype?
What is your Phenotype?
Generation Genotype
Phenotype
How many of
your babies
survived?
Genotypes of
the babies
Allele
frequency
Remember, evolution happens at a population level – place all data on the board
Questions:
Is it evolution if a trait is not passed from one generation to the next?
Did all of the mutations help/hinder you?
What are some potential challenges you faced in keeping your dragon baby alive?
What do you think would happen if they weren’t able to hunt their lentil prey and instead could only hunt
cooked spaghetti?
Graph the allele frequencies on a different sheet of paper