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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
CASE TEACHING NOTES
for
“When Wilma Met Fred: A Human Evolution Case”
by
Bruno Borsari, Biology Department, Winona State University
INTRODUCTION / BACKGROUND
Objectives
This case is a modified version of “The Dating Game: A
Case Study in Human Evolution” by Shoshana Tobias and
Clyde Freeman Herreid, published as part of the National
Center for Case Study Teaching in Science’s case collection in 1999. It is organized primarily as a case, but also as
a game that is played by all of the students in class. For the
game, students anonymously take on the role of a specific
hominin and need to select the appropriate mate in the
diverse populations of the genus Homo that lived during
the Pleistocene (1.6 million years ago to 10,000 years ago)
by paying attention to clues given by the instructor.
The case is a “clicker case.” It is presented in class
using a series of PowerPoint slides that are punctuated by
questions (aka “clicker questions”) posed by the instructor
that the students must answer. Through the PowerPoint
slide, students are introduced to the Pleistocene epoch
and then to Pleistocene hominins. The Pleistocene is a
geological epoch of great interest for human evolution
because during this time-frame our ancestors evolved all
of the characteristics that make us distinctively humans.
The focus of the case is on the physical and cultural differences among this group of hominins. This information prepares students for the game that is played in class,
which requires that they understand and can differentiate
among the traits of early humans of the genus Homo.
The case is designed to be taught at the end of an
evolution unit of the curriculum. Though not essential
for this exercise, it would be useful if students were familiar with concepts such as genetic drift, mutation, gene
flow, and nonrandom mating, and have basic knowledge
of evolution. With this background, the instructor could
pursue issues such as what forces might have driven the
evolution of specific traits in early humans.
Developed for a non-majors’ introductory biology
course, the case is also suitable for courses in evolution,
natural history, biological anthropology, and general biology for majors with modifications.
Through this case study, students will practice the
following skills:
• Understand the environment—both physical and
social—in which early humans and their recent
ancestors evolved and how this has led to what we
think of as uniquely human characteristics.
• Learn the physical and cultural differences among
early hominins of the genus Homo.
Case Teaching Notes for “When Wilma Met Fred” by Bruno Borsari
Misconceptions
• The extinction of early hominins was necessary to
allow the evolution of modern humans.
CLASSROOM MANAGEMENT
This case was written for an introductory biology class
(non-majors) with 180 students and access to a student
response system (“clickers”). It can be completed in a single
50-minute class period. Students in my class normally
work in permanent groups, but the case can be used with
or without such groups.
The case consists of a PowerPoint presentation
(~1.3MB) that is shown in class. In addition, there are
several handouts associated with the case. One of these
handouts students complete as homework, while the
others explain the game and assign students a species
role to play. There is also a handout that is used by the
instructor when the game is played. The handouts are
included at the end of these teaching notes.
The PowerPoint slides tell the fictitious story of a
group of students who have traveled abroad with their
instructor, who is a paleontologist, to Tanzania to learn
more about the origin of humans. The case concludes
with a classroom game that mimics modern TV shows
where people look for an “ideal soul mate.” Students
prepare for the game in advance, but the game is played
in class. To prepare for the game, students are assigned a
species beforehand, which they do not disclose to anyone
else in the class. Their homework assignment (see pre-
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
class assignment handout at end of notes) is to research
that species. In class, the game challenges students
to identify in the audience mates of the same species
through a set of characteristics/clues that are disclosed
by the instructor in a “quiz” show format. The game
is entertaining at the same time it is educational, and
facilitates student learning of the often challenging topic
of human evolution. It assesses their knowledge after they
have researched the main traits of one species on their
own and after being challenged by the clicker and openended questions proposed by the case up to this point.
At the beginning of class the instructor will distribute
the handout to each student making sure that the
information given to one is not disclosed to other students.
ancient Lake Turkana but in Ethiopia) have been
found that put the origin of Homo sapiens back to
195,000 years ago (http://www.eurekalert.org/pub_
releases/2005-02/uou-toh021105.php).
Optional Video Recommendation
The following links to a short video clip of less than 5 minutes
long from the History Channel about the Neanderthals:
http://www.youtube.com/watch?v=WgV6OzauVmE&
feature=related This is an excellent documentary that I
recommend showing to students to complement this topic,
perhaps at the beginning of the class period following this
case to reinforce learning about the physical and cultural
characteristics of this early human species.
Some Considerations for the Instructor
Teaching the Case
There are two current hypotheses for the evolution of
humans: the multiregional hypothesis and the “Out-ofAfrica” hypothesis, which are covered in most introductory
biology textbooks (see also http://anthropology.si.edu/
humanorigins/faq/Encarta/diversity.htm). The second
hypothesis (which this case supports) is the one usually
favored now because the genetic as well as fossil evidence
supports it better.
It is also important to point out that all four
hominin species considered in this case never lived
together. However, Homo habilis and Homo ergaster/
erectus probably overlapped in Africa, and Homo
neanderthalensis and Homo sapiens definitely overlapped
in Europe, while Homo erectus and Homo sapiens
probably overlapped in East Asia.
In addition, it is important to make a clear
distinction between “early hominids” and “humans” or
“modern humans”:
• “Hominidae” are now considered to be extinct and
extant humans, chimps, gorillas, and orangutans,
although it used to mean only extinct and extant
humans (which are now the sub-tribe Hominina
along with chimpanzees).
• “Human” refers to Homo sapiens, a convention used
by many, though not all, researchers in this field.
There used to be a distinction between “modern
humans” and archaic humans. The instructor
should be referring to archaic humans when
telling students that the first humans appeared
about 160,000 years ago (Slide 11) as opposed to
saying modern humans evolved 100,000 years ago.
However, now archaic humans are considered to
be Homo heidelbergensis and new fossils (not along
The class before the case, students are given an assignment
(see pre-class assignment handout at the end of these
notes) to select one of the four species considered in
the case (H. habilis, H. erectus, H. neanderthalensis, or
H. sapiens ) and to research and retrieve information
(individually) about that species with particular emphasis
to the following traits: origin, height/weight, build
(body type), climate/habitat in which the species was
mostly established, time range, diet, use of fire, ability
to make tools, brain size, communication skills, and any
other distinguishing feature.
At the beginning of the next class, the instructor
distributes a handout (either Table 1 or Table 2,
depending on the student’s gender) to each student,
making sure that the information given to one is not
disclosed to any other students. With Table 1, given to
male students, a checkmark on one of the four columns
of the handout indicates the species of the genus Homo
each male student is going to be, without disclosing this
information to anyone else. Similarly, all of the female
students are given a handout (Table 2), which contains a
list of 10 important traits each woman is going to select
for the choice of her mate. This information also is not
disclosed, so that nobody knows which species of Homo
each student is.
Case Teaching Notes for “When Wilma Met Fred” by Bruno Borsari
Characteristics of the Pleistocene
Slide 2 presents the first clicker question (CQ#1), which
is intended to verify whether or not students know that
Charles Darwin and other scientists also considered the
origin of humans.
Slide 3 recounts how students taking a field course
in Tanzania appear to have discovered some hominin
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
remains. This slide can be read out loud by a student
selected at random.
Slide 4 presents the second clicker question (CQ#2),
which is aimed at assessing whether students know
where Tanzania is and why the class described in the case
story traveled there.
Slide 5 presents the third clicker question (CQ#3),
which further engages students in the case by asking
whether they know what the Pleistocene was.
Slides 6–10 present the main characteristics of
the Pleistocene. This information can be read by the
instructor and expanded upon, if desired (3–5 minutes).
More specifically, Slide 6 describes when the Pleistocene
occurred within the earth’s natural history. Slides 7–9
provide more information about the Pleistocene epoch.
This is where the instructor should point out that the most
recent glaciation is the last of four major glaciations that
occurred over the past 425,000 years of the Pleistocene.
This event began about 100,000 years ago and ended
about 10,000 years ago. It was characterized by several
mild spells that allowed early human migration and
habitation at higher latitudes for thousands of years
(especially in North America).
Human Evolution
Slide 11 presents the “Out-of-Africa” theory. Africa is
considered by most scientists to be the cradle of human
origins and for decades it has been a primary center for
studies about human evolution.
Slide 12 presents the fourth clicker question of the
case (CQ#4), which evaluates the students’ knowledge
of fossilization.
Slide 13 continues the story. A student can be
selected at random to read the slide out loud.
Slide 14 invites students to join the other students
who have been studying the same species of hominin and
share their collected information about it. Allow students
to discuss their findings in groups for 5 to 7 minutes. In the
meantime, write the name of the species being considered
on the board and invite group leaders to come and report
(write) the information under each species’ name.
Slide 15 presents the fifth clicker question (CQ#5),
which asks students to classify the hominin found in the
case story.
Slide 16 presents the sixth clicker question (CQ#6),
which connects the students’ answer to CQ#5 to what
they have learned so far about Homo erectus.
Slide 17 presents the characteristics of H. erectus.
The students’ information transcribed on the board
Case Teaching Notes for “When Wilma Met Fred” by Bruno Borsari
about H. erectus is compared to the information on the
slide. At this point, corrections, comments, and remarks
are solicited to make sure that the class has learned some
physical and cultural characteristics about this species.
Slides 18–20 list the characteristics of the remaining
three species of the genus Homo. The instructor
continues to facilitate class discussion as the students’
notes written on the board are compared with the
information presented in these slides.
Slide 21 presents a timeline for when these various
hominins were alive.
Slide 22 shows the trends in cranial capacity over
time and presents the seventh clicker question (CQ#7),
which challenges students to analyze the data (and their
correlation) presented in the graph.
Slide 23 presents the eighth clicker question (CQ#8),
which asks students about the leveling off of recent brain
sizes. If the instructor wishes to, this slide presents an
opportunity to discuss further the difference in brain
size between H. neanderthalensis and H. sapiens. The
literature suggests that H. neanderthalensis had a larger
brain than H. sapiens, although at least one reference says
that H. sapiens’ brain was as large as H. neanderthalensis’
when the two species coexisted with one another, but
that it is smaller now. The reason given is that our brain
became more compact and more efficient so that it used
less energy (brains are considered to be energy hogs). This
conclusion is inferred from behavior, which is what the
instructor should bring out in discussion. Directional
selection within each species led to a larger brain—up to
a point. What anatomical change could have occurred
to allow a smaller brain with more “brain power”? If
you have already looked at the nervous system or even
the evolution of mammals, the students might be able
to come up with increased convolutions of the cerebral
cortex in answer to this question, which would provide
more surface area despite the volume being the same or
smaller than before.
Slide 24 proposes three open-ended questions that
students are told to discuss with their neighbor/s in
small groups. Each group selects a question to discuss
within a three-minute time frame. After this time, the
instructor solicits answers from the student groups. You
may want to select at random students that will report
on the outcome of their discussions.
Slide 25 shows a phylogenetic tree of our ancestors
that can be used by the instructor to summarize and/or
reiterate the main information learned to this point, and
asks about coexistence of Neanderthals with H. sapiens.
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
The “Mating/Dating” Game
Slide 26 sets up the game that is played in class. The
women (“Wilma”) in class select the “right” mate
(a “Fred” of the same species) by paying attention to
which males respond to which statement about various
species characteristics is being announced by the
instructor. How this works is, the instructor reads out
loud statements referring to attributes of a certain Homo
species as described in the Handout for Instructors (see
end of notes) for 35 attributes. When listening to this
information, the men to which the statement applies
stand up, look around, wave at the audience, and then
sit down. In this way, game participants (women in
particular), by paying attention to who is standing up
and waving at certain points in the proceedings, can
hone in on who would be their match-mate. It takes
about 25 minutes to do this. At the end, give students
half a minute to cross the classroom and reach his/her
mate and verify (by disclosing the handout) that both
students belong to the same Homo species. You win if
you connect with the “right” mate. Extra credit could
be rewarded for the first three couples that reach the
instructor and show him/her the handout indicating
that both partners belong to the same species.
Epilogue
Slide 27 reviews the common descent theory, while slide
28 reminds students that we are all connected to African
ancestors.
Slides 29–32 continue the theme of common descent,
and cites the remarkable discovery of Ardipithecus ramidus
in Ethiopia announced in a series of 11 papers published
in the October 2, 2009, issue of the journal Science.
ANSWER KEY
in Relation to Sex (2 vols). London: John Murray.
(Reprinted in 1981 by Princeton University Press)
Diamond, J. 1992. The Third Chimpanzee. The Evolution
and Future of the Human Animal. New York:
HarperCollins.
Fleagle, J. G., T.M. Brown, J.D. Obradovitch, and
E.L. Simons. 1986. Age of the earliest African
anthropoids. Science 234:1247–1249.
Finlayson, C. 2005. Biogeography and evolution of
the genus Homo. Trends in Ecology & Evolution
20(8):457–463.
Hill, K. 1982. Hunting and human evolution. Journal of
Human Evolution 11:521–544.
Leakey, R.E., and R. Lewin. 1978. People of the Lake.
Mankind and its Beginnings. New York: Doubleday
& Co., Inc.
Lewin, R. 1986. New fossil upsets human family. Science
233:720–721.
Lovejoy, C.O. 1981. The origin of man. Science
211:341–350.
Pilbeam, D. 1984. The descent of hominoids and
hominids. Scientific American 250:84–96.
Rak, Y. 1986. The Neanderthal: A new look at an old
face. Journal of Human Evolution 15:151–164.
Ranzi, C. 1982. Seventy Million Years of Man. Rizzoli
Editore-Milano, Italy.
Strickberger, M. W. 1990. Evolution. Boston: Jones &
Bartlett Publishers.
Stringer, C.B. 2003. Human evolution: Out of Ethiopia.
Nature 423, 692–695. doi:10.1038/423692a
Stringer, C.B., and P. Andrews. 1988. Genetic and fossil
evidence for the origin of modern humans. Science
239:1263–1268.
•
Answers to the questions posed in the case study are
provided in a separate answer key to the case. Those
answers are password-protected. To access the answers
for this case, go to the key. You will be prompted for a
username and password. If you have not yet registered
with us, you can see whether you are eligible for an
account by reviewing our password policy and then
apply online or write to [email protected]
Acknowledgements: This material is based upon
work supported by the NSF under Grant No. due0618570. Any opinions, findings, conclusions, or
recommendations expressed in this material are those of
the author and do not necessarily reflect the views of
the NSF. I am grateful to the comments of anonymous
reviewers that helped tremendously to increase the clarity
and quality of this case.
REFERENCES
Copyright held by the National Center for Case
Study Teaching in Science, University at Buffalo, State
University of New York. Originally published January 25,
2011. Please see our usage guidelines, which outline our
policy concerning permissible reproduction of this work.
Arensburg, B., A.M. Tillier, B. Vandermersch, H.
Duday, L.A. Schepartz, and Y. Rak. 1989. A middle
Paleolithic human hyoid bone. Nature 338:758–760.
Darwin, C. 1871. The Descent of Man, And Selection
Case Teaching Notes for “When Wilma Met Fred” by Bruno Borsari
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
PRE-CLASS ASSIGNMENT
for
“When Wilma Met Fred: A Human Evolution Case”
Your assignment is to independently research one of the four species of the genus Homo that will be considered in this
case: H. habilis, H. erectus, H. neanderthalensis, or H. sapiens. Select one and then, working on your own, research and
collect information about it with a particular emphasis on the following traits:
• Origin
• Height/weight
• Build (body type)
• Climate/habitat in which the species mostly established
• Time range
• Diet
• Use of fire
• Ability to make tools
• Brain size
• Communication skills
• Other distinguishing features
NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
THE GAME
for
“When Wilma Met Fred: A Human Evolution Case”
The class game described in this handout is an important feature of this case.
The women in the class (Wilma) will have to select the “right” mate (a “Fred” of the same species) by following attentively
the dynamics of the game and paying attention to who responds to which statements made by the instructor describing
attributes of particular species of the genus Homo.
The men in the class will each be given a separate handout that will have a checkmark in one of the four columns of
a table indicating the species of the genus Homo each male student is going to be. When you get your species role
assignment, do not show it to anyone else. Similarly, all of the women in the class will be given a handout that contains
a list of 10 important traits each woman is going to select for the choice of her mate. One of the species will be checkmarked. This information as well should not be disclosed so that nobody knows which species of Homo each student is.
The instructor will read out loud statements referring to attributes of a certain Homo species. When listening to this
information, the men in the class who posses those traits will stand up when the trait is read out, look around, wave at
the audience, and then, sit down. In this way, game participants (women in particular, but also men), by paying close
attention to who is standing up and waving at particular points in the process, will be able to pick out who is their match.
It will take about 25 minutes to accomplish this. At the end, half a minute will be dedicated for each individual to reach
his/her mate and verify (by disclosing the handout) that both of you belong to the same Homo species.
You win if you connect with the “right” mate.
NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
HANDOUT FOR MALE STUDENTS
for
“When Wilma Met Fred: A Human Evolution Case”
Category
H. erectus
H. habilis
H. sapiens (us)
H. neanderthalensis
Range
China, Europe,
Africa
First found in
All over
Tanzania; some put
Kenyan material into
H. rudolfensis
Europe, western Asia.
Ht/wt
1.6–1.8 m. M: 65
Kg.
Less than 1.6 m.,
very light.
Modern – as in
European
1.7m., 65–80 Kg.
Build
Same as human.
Lighter than humans
Modern
Very muscular.
Climate/habitat
African savannacold Europe.
All over, especially
warmer regions
Cold N. Europewarmer Israel.
Time Range
1.5 mya–200,000 ya. 2.0–1.6 mya
160,000 ya–to present
120,000–28,000 ya.
Diet
Small game, plants,
nuts, fruit, some
large game.
Marrow, scavenging,
seasonal vegetation.
Hunting, fishing, wild
grains, plants, big
game. Cooked.
Plants, nuts, fruit, big
game animals.
Use fire?
Yes; cooked food.
?
Yes; hearths.
Yes; cooked food on
hearths.
Tool making?
Hand axes, scrapers.
Simple stone tools.
Varied material,
innovation.
Advanced, little
variation
Brain size
750–1140 cc.
560–700 cc.
1040–1595 cc.
1400–1800 cc.
Communication
skills
?
?
Art, language, ritual,
music.
Probably; used some
rituals.
Distinguishing
characteristics
Heavy brows, strong First evidence of
jaws and teeth.
stone tools.
Innovation, math,
complex tools with
regional differences
and dialects.
Agriculture, religion,
warfare.
Heavy brows, sloping
forehead, large
nose and lower jaw.
Evidence of clothes,
burial ceremonies.
NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
HANDOUT FOR FEMALE STUDENTS
for
“When Wilma Met Fred: A Human Evolution Case”
ATTRIBUTES LIST OF MY MAN OF CHOICE: H. erectus
1. You are about 1.75 m. tall, modern build, strong face, heavy brows and strong jaws.
2. Your brain size must be between 750 and 1140 cc.
3. You can build hand axes and scrapers.
4. You lived between 1.5 million years ago and 200,000 years ago.
5. You do not need to impress me by inventing “new things.”
6. You must be able to use that hand ax to protect me/us from predators and enemies.
7. I do not care whether you can or cannot tell me that you love me.
8. You must be able to build me a fire when I get cold.
9. When you take me out to dinner I want to go eat small/large game, plants, nuts, fruits.
10.
…………and I like my food to be cooked.
ATTRIBUTES LIST OF MY MAN OF CHOICE: H. habilis
1. You are less than 1.6 m. tall and very light.
2. Your brain size must between 560 and 700 cc.
3. You know how to build simple stone tools.
4. You lived between 2.0 and 1.6 million years ago.
5. You do not need to impress me by inventing “new things.”
6. You must be able to throw rocks to our enemies in order to protect me.
7. I do not care whether you cannot tell me that you love me.
8. Just sleep close to me when I get cold at night.
9. When you take me out for dinner I want to eat small game, plants and soft fruits.
10.
…………and I like my food raw.
ATTRIBUTES LIST OF MY MAN OF CHOICE: H. neanderthalensis
1. You are about 1.7m. tall, stocky, muscular, heavy brows, strong jaws, large nose.
2. Your brain size is almost 1800 cc.
3. You know how to build wood and stone tools.
4. You lived between 120,000 and 35,000 years ago.
5. You must be able to impress me by inventing new things (jewelry, tools).
6. You are strong enough to protect me but when in danger you call out for help.
7. I do not care whether you can or cannot tell me that you love me.
8. You must be able to build me a fire and give me hides to wear when I am cold.
9. When you take me out for dinner I want to eat mammoth and big game.
10.
…………and I like my food to be cooked.
ATTRIBUTES LIST OF MY MAN OF CHOICE: H. sapiens
1. You are about 1.55–1.8m.tall.
2. Your brain size between 1095 and 1595 cc.
3. You are the most creative in designing and building tools.
4. You lived between 100,000 years ago and present time.
5. You must be able to impress me by inventing “new things” all the time. You are so creative!
6. Your creative mind is very effective in protecting me from enemies and danger.
7. You are capable of overwhelming me by sweet, loving words.
8. You must be able to build me a comfortable shelter to protect me from the cold.
9. When you take me out for dinner I want to eat meat, fish, wild grains, plants, big game.
10.
………….and I like my food to be cooked.
NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
HANDOUT FOR INSTRUCTORS
for
“When Wilma Met Fred: A Human Evolution Case”
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
I do not care whether you can or cannot tell me that you love me.
Your brain size must be between 750 and 1140 cc.
You must be able to build me a shelter to protect me from the cold.
You lived between 120,000 and 35,000 years ago.
When you take me out to dinner I want to eat small or large game, plants, nuts, fruits.
You are about 1.55 to 1.8 m. tall.
You must be able to impress me by inventing new things (jewelry, tools).
You are so creative and capable of inventing new things all the time.
You are less than 1.6 m. tall and very light.
You lived between 1.5 million years ago and 200,000 years ago.
When you take me out for dinner I want to eat mammoth and big game.
You must be able to cook my food.
You can build me wood and stone tools.
You lived between 2.0 and 1.6 million years ago.
You are good at throwing rocks at our enemies so that you can protect me.
Your brain size is between 1095 and 1595 cc.
You must be able to make me a fire and cover me with hides when I am cold.
You are about 1.75 m. tall, modern build, strong face, heavy brows and strong jaws.
You must be able to build simple stone tools.
You are capable of overwhelming me with sweet, loving words.
You do not need to impress me by inventing “new things.”
Just sleep close to me when it gets cold at night.
You lived between 100,000 years ago and the present time.
You can build hand axes and scrapers.
You do not need to cook my food as I like it raw.
Your brain size is almost 1800 cc.
When you take me out for dinner I want to eat meat, fish, wild grains, plants, big game.
You must be able to use a hand ax to protect me from our enemies.
You are about 1.7 m. tall, stocky, muscular, have heavy brows, a strong jaw, and large nose.
You must be able to build me a fire when I get cold.
You are the most creative in designing and building tools.
Your brain size must be between 560 and 700 cc.
Your creative mind is very effective in protecting me from enemies and danger.
When you take me out for dinner I want to eat small game, plants and soft fruits.
You are strong enough to protect me but when in danger you can call out for help.
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