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Family That Walks on All Fours
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Classroom Activity
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Activity Summary
Students use a viewing guide while watching a program about members
of a Turkish family who walk on four limbs and discuss program
themes after watching.
Learning Objectives
Students will be able to:
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copy of the "Handwalkers Raise Questions" student handout (PDF
or
HTML)
Background
In early 2005, scientists discovered five of 11 siblings in a
Kurdish family living in southern Turkey who walked on all fours.
Uner Tan, the Turkish scientist who first reported the discovery,
believed that studying the family could shed light on evolution. He
suggested the family members were a "throwback" to a much earlier
time in human prehistory. Many scientists disagreed with his
conclusions.
A team of German scientists thinks there may be one or a few genes
responsible for bipedality. Most scientists believe that a complex
trait like walking upright is a consequence of changes to many genes
over a long period of time.
Some scientists believe that brain damage caused by a genetic
mutation may have influenced how the family members walk (all five
siblings are mentally handicapped). Some scientists also think that
environmental influences played a role, including the idea that the
siblings may never have made the transition from an infant "bear
crawl" they used to move around.
In this activity, students will track four themes within the program
and prepare a presentation sheet on each assigned theme and consider
some of the ethical issues of studying and filming this family.
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Organize students into four teams. Assign each team one of the
following themes to take notes on as they watch the program:
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Possible reasons for why some family members are handwalkers.
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Treatment of the family by outsiders (e.g., villagers,
scientists, and film producers).
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Neurological tests that were performed and the conclusions
drawn.
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Interactions among family members and the beliefs they hold.
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Distribute a copy of the student handout to each team before
viewing. Discuss appropriate background information with
students, and explain that sensitive issues related to culture
and physical challenges faced by the family are addressed in the
program.
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Show the program and have students individually take notes on
the theme their team has been assigned.
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After watching the program, have students meet in their teams to
discuss their notes. Have each team prepare a presentation sheet
that includes information and ideas from each team member.
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Have teams share their presentation sheet and any questions that
came out of their teamwork. (See Activity Answer on page 4 for
possible theme presentation material. Accept all reasonable
answers.) Ask students in the rest of the class if they agree
with what the team has presented. If students don't agree, ask
them to explain why and provide evidence from the program that
will support their opinions. Based on the evidence presented in
the program, which of the hypotheses presented do students think
best explains the siblings' condition? Why?
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To conclude, discuss some of the ethical issues related to
studying and filming a family with challenges such as those of
the family in the program. Assign each team one or two ethical
issues to explore. Ask students to include in their discussion
how studying this family may be helpful to scientists and
others, and how it could be both helpful and hurtful to the
family. Have teams share what they discussed.
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As an extension, have students research and present information
on Turkey and Turkish culture.
Suggested points related to themes listed on the student
handout:
Possible reasons for why some family members are handwalkers.
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One scientists thinks the family members are "throwbacks"
exhibiting traits that have resurfaced after being absent for
generations.
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Most scientists do not believe that ancient genes resurface in
living organisms.
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A team of German scientists believe there may be a gene or small
set of genes for bipedality. Many scientists believe bipedality
cannot be traced to a single gene, thinking that evolution
usually proceeds more gradually and involves many mutations.
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Some scientists think that brain damage may contribute to the
five siblings' inability to walk on two legs, although others
with this sort of damage have been known to walk on two legs.
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Some scientists think that environmental factors played a large
role in how the family members walk.
Treatment of the family by outsiders.
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Family members experienced isolation and ridicule from members
of their community. Children threw rocks at family members, who
were outcasts because of their challenges. After they rebuilt
their house and ran out of water, they received no assistance
from the community.
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The visiting scientists and film crew placed a spotlight on the
family, perhaps adding to the local tension.
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The crew and scientists working on the film brought the family
walkers and parallel bars, arranged for them to work with a
physical therapist, and took them to the beach.
Neurological tests that were performed and the conclusions drawn.
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The neurologist gave family members simple tasks to complete. A
discrepancy arose between how well the siblings performed in
front of the neurologist and the skills they exhibited in
private. For example, Safiye didn't perform well using a
pegboard, but later she was observed tying her scarf.
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MRIs were used to study family members' brains. It was
discovered that Huseyin, Hacer, and Safiye each had a shrunken
area in the middle of the cerebellum. However, the
presence of a small cerebellum may not be enough to explain why
these siblings walk on all fours, as other people with a similar
condition can walk upright.
Interactions among family members and the beliefs they hold.
Family members cared for and supported each other. -
The family believed God was testing them, and that they would be
rewarded after death for doing God's deeds in life.
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The family is Muslim and does not believe in evolution. The
father felt being compared to other species was degrading to his
family.
Web Sites
NOVA—Family That Walks on All Fours
www.pbs.org/nova/allfours/
Find articles, interviews, interactive activities, and resources in
this companion Web site to the program.
Cerebellum
www.sci.uidaho.edu/med532/cerebell.htm
Explains the cerebellum's role in walking.
Laboratory of Neuroimaging
www.loni.ucla.edu/About_Loni/education/AB_Cerebellum.shtml
Describes the function of the cerebellum.
Turkish Culture Foundation
www.turkishculture.org
Provides information on many aspects of Turkish culture.
Books
The Brain Explained
by Daniel Drubach. Prentice Hall, 2000.
Describes the structure and function of different parts of the brain
and disorders that can affect the brain.
Turkey
by Chris Eboch. Lucent Books, 2003.
Includes information on the geography of Turkey and Turkish culture.
The "Handwalkers Raise Questions" activity aligns with the following
National Science Education Standards (see
books.nap.edu/html/nses).
Grades 9-12
Science Standard C
Life Science
Biological Evolution
Classroom Activity Author
Developed by WGBH Educational Outreach staff.
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