A Cutting Decision
Running head: A CUTTING DECISION
A Cutting Decision: A Review of Computer Based Alternatives to Dissections
Alix Gray Burdett BSc, BEd
University of British Columbia
A paper for ETEC 500: Research Methodology in Education
April 2009
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A Cutting Decision
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Introduction
Dissection is an ancient and classical practice used to discover animal anatomy and
physiology (De Villier & Monk 2005). Our current understanding of animal anatomy is
owed to the practice of dissection. Indeed, the literal translation of the word anatomy is
“to cut up”. Historically, dissection was used in education for the professional training of
physicians and veterinarians (Hug 2005). Dissection was introduced in to general, nonmedical, education in the early 20th century (Kinzie et al. 1993). According the Kinzie et
al. (1993), dead frogs became available from American commercial suppliers between
1910 and1920 and frog dissection had become an established high school biology
laboratory by the 1960s. Orlans (1988) estimated that in 1988, 75-80% of American high
school biology students dissected frogs.
Starting in the late 1980’s a series of American judicial and legislative decisions
protecting the rights of students choosing not to participate in dissections has prompted
students, parents, teachers and administrators to reconsider the practice of dissection
(Orlans 1988). As a relatively new high school biology teacher, I am faced with the
decision of whether or not to include dissections in my course program. While I debate if
the pedagogical benefits of dissection outweigh the ethical problems, I am curious if
alternatives to traditional dissections can provide the same pedagogical benefits (without
the ethical implications). The purpose of this literature review is to help inform my
decision about whether or not to include traditional or alternative dissections into my
biology courses.
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Introduction to Literature Review
Literature debating the pedagogical and ethical implications of dissection in
biology education date back to the 1960’s. This debate has stimulated research into
alternatives to traditional dissections. Although not a prevalent area of research, there are
enough studies comparing alternatives to traditional dissections that this topic has
recently been reviewed. In his comprehensive review, Akpan (2001) examines the use of
simulations in biology education, including simulated dissections. Based on his analysis
of the available empirical research, Akpan suggests that, “…simulated dissection and
actual dissections typically lead to equivalent performance on achievement tests,
simulations used before actual dissections may enhance dissection performance, and
experiential simulations facilitate learning from subsequent didactic instruction.”
De Villiers & Monk (2005) also review a series of studies from the 1960’s to the
1990’s that investigated a variety of dissection alternatives. The alternatives studied
included physical models, film strips, stereoscopic slides combined with audiocassettes,
lecture only, videos and interactive video disks. De Villiers & Monk conclude:
What little research evidence there is points to the following conclusions:

Declarative knowledge is equal, if not better, when using alternatives to
dissection;

Guided learning, no matter whether with dissections or alternatives, brings both
gains in declarative knowledge and personal satisfaction;

Well-designed models, as substitutes for actual specimens, can produce equal
performance in skills; and
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
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The use of interactive experiences that learners can control at their own pace is of
benefit. (De Villiers & Monk, 2005 p. 589_
Akpan and De Villier & Monk’s reviews are comprehensive, but do not include more
recent studies conducted since 2000, or those that focus on computer based simulations.
In the following review, I will examine a collection of four studies, all conducted since
2000, that address the question of the value of traditional dissections, and compare them
to computer based alternatives. In the first paper reviewed, Hug (2007) conducts a
qualitative study questioning the pedagogical value of traditional dissections. The other
three papers are all studies that compare computer based alternatives to traditional
dissections.
Analysis and Critique
Hug (2007)
In her 2007 qualitative study, Barbara Hug wonders if the pedagogical return of
dissection is worth the ethical compromises that the practice can require. She asks “Is
dissection simply a procedural manipulation on the part of students? Or does it succeed in
bringing meaning to the content of the (larger) lesson?” To address this question, Hug
examined videotape taken in three American middle school classrooms during dissections
of a yellow perch and a sea lamprey. The dissections were part of a larger lesson on
ecological interactions. To produce a descriptive synthesis of the lessons, Hug divided the
lessons into three phases (setting up, carrying out, and making sense of the tasks) and
analyzed each based on criteria concepts of “worthwhile” (appropriate content was
highlighted) and “meaningful” (students make connections to previous experiences).
In her analysis, Hug found that in all three phases of the lesson, a focus on the
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procedural logistics overshadowed the teachers’ ability to highlight appropriate content
and the students’ abilities to make connections. Hug concludes that it is unclear if
dissection added depth to the students' understanding of the structure and function of fish
body systems or of the larger ecological lesson. Hug adds, “If the curricular goal was the
observation of anatomical structures, and then sense-making about the implications of
their observations (i.e. connections to structure-function), the students could have
observed images, simulations, or demonstrations —without the killing of animals—or
perhaps observed animal dissection demonstrations.”
Due to the nature of qualitative studies, one needs to be wary of potential biases
of the author. An examination of Hug’s other publications (e.g. see Hug 2005) reveals
that she is has previously written opinion pieces that portray traditional dissections
negatively. As such, one needs to keep these biases in mind when considering Hug’s
conclusions in this study.
If we accept Hug’s conclusions that the pedagogical gains may not outweigh the
ethical problems with traditional dissections, and that alternatives should be considered,
then it would be prudent to examine the pedagogical implications of using alternatives.
The next thee studies all compare traditional dissections to computer based alternatives.
Kariuki & Paulson (2001)
In this quasi-experimental study, Kariuki & Paulson (2001) wonder if there a
difference in student achievement between students using a CD-ROM dissection tool
versus those dissecting preserved specimens. Their study sample included 104 general
biology students from a rural high school in Tennessee. The students all had the same
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teacher, but were spread over four classes. The students in each class were randomly
assigned into one of two groups; an experimental group or a control group. The
experimental group dissected an earthworm and a frog using a CD-ROM dissection tool
while the control group dissected preserved specimens. The measure of student
achievement was based on a test that was designed to probe student understanding of
structure and function of organs and ability to identify worm and frog anatomy. The
collected data was analyzed using a t-test. Kariuki & Paulson found that the control
group (i.e. those who dissected the preserved specimens) scored significantly higher on
the test than those students who used the CD-ROM. They conclude that these finding
suggest that the authentic task of dissection increased retention of knowledge relative to
the CD-ROM experience.
In their paper, Kariuki & Paulson included a detailed description of both the
school’s socioeconomic background as well as a detailed description of the ethnic,
gender, and age makeup of their sample. This detail provides the reviewer with a rich
context with which to judge the context of the study. Internal validity was supported this
study by good control measures and replication. All students had the same teacher, and
both groups were exposed to the exact same pre-lab preparation and post-lab review and
testing procedures. By dividing each of the four classes into control or experimental
groups, the effect was four replicates. To improve external validity, this study should be
conducted in other schools in different areas. The findings of this study are contrary to
the finding of many other studies comparing alternatives to traditional dissections, as in
the following three studies.
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Akpan & Andre (2001)
In this study, Akpan & Andre (2001) were interested in the effects of participating
in a computer based simulated frog dissection on learning frog anatomy. The study
included 80 seventh grade students in life science course a mid-west American middle
school. Each class was assigned to one of four experimental groups including, dissection
only (DO) or simulation only (SO). The other two groups engaged in dissection before
simulation (DBS) and simulation before dissection (SBD). Each group was administered
both a pre-test and a post-test and data was analyzed statistically. No significant
differences between groups was found in the pre-test data. Analysis of the anatomy and
morphology achievement posttest revealed that students in all groups improved their
anatomical knowledge from pre-test to post-test. However, the students in the simulation
only and the simulation before dissection groups improved more, with the simulation
before dissection group improving the most. Akpan & Andre conclude that while
computer based simulations may provide an experiential base that can improve
subsequent learning, the highest learning level is achieved when combined with real
dissections.
This study is rare in that the authors included an analysis of the limitations of their
own study. Who better to speculate on limitations than the author’s themselves. Some of
the limitations discussed include: homogenous sample (white, middle class), exclusion of
students with special needs, pretest effects on posttest results, time lapse between pretest
and post test and possible maturation in between and smaller sample size. Additionally,
because whole classes were assigned to groups (versus random assignment of individuals
within each class) this study represents a nonequivalent control group design., with
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potential threats to internal validity.
Predavec (2001)
This study focused on first year undergraduate biology students and rat
dissections. Practical classes were randomly assigned to an experimental “E-Rat” group
(n = 233) or to a conventional dissection group ( n = 168). The study investigated the
differences between the two groups on a rat anatomy test. A week after participating in
the activities, all students were administered a multiple choice test with questions based
on three formats: (1) text only, (2) pictures of structures and dissections and (3) real
dissected rats and prepared slides. Upon statistical analysis, Predavec found that the ERat group scored on average 7.4 % better than the conventional dissection group, with a
significant difference across all three question types. The strongest difference was found
in the picture based questions. Predevac speculates that the immediate responses and
feedback and clear representation of structures afforded by the E-Rat software may have
contributed to the increased success of the experimental group. Predevac conceded that
while E-Rat does not teach dissection skills, the pedagogical goal of the activity was to
teach rat anatomy. He concludes that this study supports the idea that alternatives can
equally (if not better) achieve the same pedagogical goals as conventional dissections.
The large sample size in this study reduces many confounding variables that may
exist between the preformed practical class groups. Good controls were used between the
groups including making sure both groups spent the same amount of time on their
activities. One possible confounding variable could be the “novelty effect” of using a
computer simulation afforded by the E-Rat software.
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Synthesis and Conclusion
A common theme that ties the four articles I reviewed is a general consensus that
conventional dissections have ethical problems, and thus pedagogical benefits should be
considered. The first article (Hug 2007) is a qualitative analysis of the pedagogical
benefits of conventional dissections. Hug concludes that the pedagogic return may not
outweigh the ethical concerns, and thus alternatives should be considered. The next three
articles, seek to consider alternatives by comparing the pedagogical benefits of computer
based alternatives to conventional dissections. The three studies I examined all used
quasi-experimental methods to investigate dissection alternatives for organisms including
earthworms, frogs and rats and at different age levels (middle school, high school and
undergraduate). All three studies focused on the effects on students achievement
(measured by tests), but also considered gender differences and student attitudes (not
discussed above). One thing I found strange is that none of the studies included a control
group where students did no dissection, real or simulated. Such a control group could
expose an argument for no dissections at all, especially because of the time required for
both types of activities.
The findings from the three studies are not in agreement, with Kariuki and
Paulson concluding that conventional dissections are best, Akpan and Andre concluding
that simulation before dissection is best and Predevac concluding that simulations are
best. Although other alternatives to conventional dissections have been studied and
reviewed, studies focusing on computer based simulations are scarce. Due to the
contradictory findings of studies I reviewed, more research is needed in to the
effectiveness of computer based alternatives on student achievement. (words: 2075)
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References
Akpan, J. P. (2001). Issues associated with inserting computer simulations into biology
instruction: A review of the literature. Electronic Journal of Science Education
[Online] 5(3). Available: http://unr.edu/homepage/crowther/ejse/ejsev5n3.html
Akpan, J.P., Andre, T.(2000). Using a computer simulation before dissection to help
students learn anatomy. Journal of Computers in Mathematics and Science
Teaching 19(3), 297 – 313.
De Villiers, R. and Monk, M. (2005). The first cut is the deepest: reflections on the state
of animal dissection in biology education. Journal of Curriculum Studies, 37(5),
583–600.
Hug, B. (2005) A reaction to de Villiers and Monk's 'The first cut is the deepest'. Journal
of Curriculum Studies 37(5) , 601-606.
Hug, B. (2007) Re-examining the practice of dissection: What does it teach? Journal of
Curriculum Studies, 40 (1), 91-105.
Kinzie, M.B., Strauss, R., & Foss, J. (1993). The effects of an interactive dissection
simulation on the performance and achievement of high school biology students.
Journal of Research in Science Teaching, 30(8), 989-1000.
Orlans, F. B. (1988) Debating dissection. The Science Teacher. 55, 36-40.
Predavec M (2001) Evaluation of E-Rat, a computer-based rat dissection, in terms of
student learning outcomes. Journal of Biological Education, 35, 75 - 80.