Cell Biol Educ 4(2): 128-131 2005
DOI: 10.1187/cbe.05-01-0057
© 2005 American Society for Cell Biology
Points of View: A Survey of Survey Courses: Are They Effective?
A Case for Nonsurvey Introductory Biology Courses
David Becker
Department of Biology Pomona College Claremont, CA 91711
Note from the Editors Points of View (POV) addresses
issues faced by many people within the life science education community.
Cell Biology Education (CBE) publishes the POV Feature to present two or
more opinions published in tandem on a common topic. We consider POVs to be
"Op-Ed" pieces designed to stimulate thought and dialogue on
significant educational issues. Each author had the opportunity to revise or
add to his/her POV after reading drafts of the other's POV.
In this issue, we ask the question, "Are survey courses still
viable for introductory biology?" The POV question is related to the
ones asked by the National Research Council in the recent feature by Jay Labov
(www.cellbioed.org/articles/vol3no4/article.cfm?articleID=132)
and continues to be a subject of debate by many science departments, not just
biology. Often the discussion is split not only by perceived value of the
survey course, but also by the size of the institution. Therefore, we present
four POVs, plus a framing POV to set the tone. The overview was written by
Arri Eisen, who is a senior lecturer in Emory University's Biology Department
and the director of the Program in Science & Society. Representing the
Anti-Survey, Large University is Janet M. Batzli, Associate Director of the
nontraditional Biology Core Curriculum at the University of Wisconsin at
Madison. The Anti-Survey, Small College perspective is presented by David
Becker, who is an Associate Professor and Magdalena R. and John P. Dexter
Professor of Botany in the Department of Biology at Pomona College. Presenting
the Pro-Survey, Large University perspective is Douglas M. Fambrough,
Professor of Biology at The Johns Hopkins Department of Biology and Scientific
Director of the Searle Scholars Program. Finally, the Pro-Survey, Small
College POV was coauthored by Mary Lee Ledbetter and A. Malcolm Campbell.
Ledbetter is a Professor of Biology at College of the Holy Cross and a 2003
NSF Director's Award recipient. Campbell is an Associate Professor of Biology
at Davidson College and a co-Editor-in-Chief of CBE. Readers are
encouraged to compare the authors' perspectives and share their thoughts and
reactions using the online discussion forum hosted by CBE at
http://www.cellbioed.org/discussion/public/main.cfm.
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OUR MOTIVATION
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In spring of 1998, the Biology Department at Pomona College changed from a
two-semester survey introductory biology sequence to a core set of three
courses, none of which is a traditional survey course. We had been wrestling
for several years with a number of issues regarding the survey courses,
including 1) what topics to include and exclude, 2) the perception by our
students that these survey courses were "like high school
biology," 3) the anonymity felt by students in the large (for us: 90-120
students) lectures, and 4) the impersonality of giving those lectures. We
finally made a breakthrough when we went through the exercise of starting from
scratch to design an introductory curriculum that 1) we would enjoy teaching,
2) would introduce our students to the fundamental principles and methods of
practicing biology, and 3) would excite our students about biology in
general.
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THE COURSES
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We decided that the first course would be centered on the thread that runs
through all types of biology: genetics (see
Table 1). Genetics is offered
in the spring semester so students can take the first semester of general
chemistry in the fall semester. The Introductory Genetics course (current text
is Genetics, Hartwell et al., or Principles of
Genetics, Snustad and Simmons, depending on section) starts with
transmission genetics, moves to the central dogma and molecular genetics, then
finishes with population genetics. This introduction to biology via genetics
sets the stage for the remaining two core courses: Cell Chemistry & Cell
Biology and Ecology & Evolution. Introductory Cell Chemistry & Cell
Biology covers basic biochemistry, membranes, membrane transport, action
potentials, intermediary metabolism, and a number of additional aspects of
cell biology. Introductory Ecological & Evolutionary Biology includes
evolutionary and population biology, behavioral and community ecology, and
conservation biology. Both Cell Chemistry & Cell Biology and Ecology &
Evolution are taught as sophomore-level courses (text for Cell Chemistry &
Cell Biology is World of the Cell, Becker [no relation], Kleinsmith,
Hardin, and the texts used for Ecology & Evolution are Essentials of
Ecology, Townsend, Begon, and Harper, plus Evolutionary
Analysis, Freeman and Herron). Students are introduced to primary
literature in both courses. The laboratory components of cell Chemistry &
Cell Biology and Ecology & Evolution emphasize the processes of
biology: hypothesis formulation, experimental design, performing experiments,
analysis of data, and communication of results. In each course, students
design projects, conduct experiments, and report (orally, in journal-article
format, and/or by poster; Figure
1) their findings. Upper-level courses are available as a
smorgasbord, each having either Cell Chemistry & Cell Biology or Ecology
& Evolution as a prerequisite. Thus, students may start taking upper-level
courses as early as the spring of their sophomore year.
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Figure 1. Poster session in Cell Biology & Cell Chemistry. Student pairs design
and carry out projects on photosynthesis in which they ultimately measure and
express rates of photosynthesis as light-dependent oxygen evolution. Projects
this year included ultraviolet B effects; comparisons among C-3 plants, C-4
plants, and Crassulacean acid metabolism plants; circadian rhythm effects;
elevated CO2 levels; and foliar iron application. Students present
their work to each other in a poster session, in which peer evaluation is an
important aspect. Their previous project (on succinate dehydrogenase) was
presented via oral presentations and in papers written in journal-article
style.
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Course Formats
For all three introductory courses, we opted for depth at the expense of
breadth. The primary objective was to get beyond the descriptive aspects to
more interesting and even unresolved issues. For Cell Chemistry & Cell
Biology, for example, this meant talking about mechanisms and strategies for
regulation of pathways and processes, while illustrating how models have
changed over time and giving multiple examples when there are competing
models. To the extent that we can, we describe seminal experiments to include
not only what we know about a topic, but also how we know
it. The goal is to get students to think critically about what they are
learning, gain an appreciation for the practice of biology, and find the
process exciting enough to continue in biology. In addition, this format is
much more interesting for us to teach. We want our students to understand that
we are not biologists because we like to memorize information, but rather
because we like to use the information to ask and answer questions about
biology.
All three courses were developed by the three subsets of the biology
faculty that teach them, and all three course designs were presented to and
vetted by the department as a whole. Even with different faculty teaching the
different sections, we felt it was desirable for content to be consistent. For
each course there is an "equalizer" that describes in some detail
the topics covered. Thus, those teaching Cell Chemistry & Cell Biology and
Ecology & Evolution know exactly the extent of genetics background their
students have when they enter each course. Likewise, for upper-level courses,
we know quite specifically to what topics the students have been exposed and
to what levels. Additionally we know they have begun to read the primary
literature, so we can opt to make heavy use of it at the outset in upper-level
courses.
Organismal Biology. I can hear the organismal biologists
moaning (or worse) as they read about our core course contents. This is an
issue that we discussed at length during the formulation of our introductory
curriculum, and the decision to omit organismal biology per se from the core
courses came with the following two conditions: 1) we would consciously choose
a variety of organisms for use in the labs for the three courses and would
spend appropriate time describing each organism, placing it in a larger
context; and 2) our majors are required to select at least one upper-level
course (with lab) that qualifies as organismal (addresses topics at the level
of the organism for a majority of the course). Examples of organismal courses
include Animal Physiology, Plant Physiology, Animal Behavior, and Comparative
Endocrinology. Personally, I don't feel that we have been successful in these
attempts to include biology studied at the organismal level. I expect that
next year we will take up the organismal biology issue again. Some biology
departments have four courses in their introductory/core sequences, and that
is one of the possible solutions we will discuss. To keep the small sections
in the introductory courses will be a challenge, however, if we add a fourth
course. Maintaining small class sizes was one of the issues that led us
originally to the sequence of three courses, and it remains to be seen if we
would be able to staff a fourth core course.
Small Multiple Sections. Just as significant as the course
content change, we also adopted the multiple-small-section model, à la
calculus. A full-time faculty member teaches each section, including the
weekly lab section. We currently teach four sections of Introductory Genetics
each spring, three sections of Introductory Cell Chemistry & Cell Biology,
and two sections of Introductory Ecological & Evolutionary Biology.
Section sizes are typically 24-32 students, which permits the classes to be
much more interactive. Because the faculty member teaches both class and lab,
he or she gets to know the students quite well and vice versa. Small classes
also permit more overt connections between classroom topics and lab
activities. Students and faculty alike are much happier with the small
sections, but a consequence of the increased staffing requirements is that
fewer upper-level courses are offered.
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DID WE SUCCEED?
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Beginning with a genetics course addressed the issue of our students' first
biology course not appearing to be a repeat of a high school class. Nearly all
of our students have taken biology in high school, and significantly more than
half have taken advanced placement (AP) biology. We did a study and an
experiment prior to 1998 to address the question of whether or not we should
place students who scored a 4 or 5 on the AP biology exam out of the first
course in our survey sequence. The study compared AP scores of students who
took the first survey course with the grades they earned in the course. There
was no correlation between AP score and college survey grade and, furthermore,
students who had not taken AP biology in high school fell in the same
distribution of grades as the students who had. We had no way to test our
hypothesis directly, but we felt that the familiarity of topics in the survey
course gave the students a false sense of competence, and our level of
expectation for their performance exceeded theirs. This disconnect between
performance and expectations resulted in a less-than-satisfactory situation.
The experiment we performed was to offer students who had scored 5 on the AP
exam the choice to skip the first course and enter the second one directly.
Skipping the first course overwhelmed the handful of students who selected
that option. They all performed quite poorly in the second course, probably
due to a variety of factors. They had not experienced the adjustment to
college biology courses (especially the labs and the exams), they were
first-year students in a class of sophomores and juniors, they had not been
through a semester of general chemistry, and they were making the general
adjustments to college life in their first semester on campus. Not
surprisingly, we do not place any students out of Introductory Genetics in the
new curriculum.
The smaller class sizes successfully addressed the other issues listed
above. Faculty and students engage with the material together in the classes,
with discussions in addition to lectures. Even the lectures can follow a more
Socratic method. Anonymity and impersonality have disappeared from our
introductory courses.
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QUESTIONS OF CURRICULAR FIT
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Nonmajors take the genetics course if they wish to take a biology course.
Consequently, a number of examples used and topics discussed are of practical
value and popular interest. For example, human genetic diseases are used
frequently as examples, eugenics is discussed, and both genetic counseling and
agricultural breeding applications are included in the quantitative genetics
and population genetics content. If a student is going to take a single
biology course in college, we feel genetics is the appropriate one, and
typically one-half of the students in the Introductory Genetics class do not
major in the three possible life science majors: biology, neuroscience, or
molecular biology.
One difficulty that arises as a consequence of our new introductory
curriculum is placing transfer students into the appropriate course.
Typically, there is some redundancy with introductory courses they have taken
elsewhere, but there is enough difference that in most cases the transfer
students are best served by taking all three of our introductory courses. We
have to consider transfer students on a case-by-case basis, and fortunately we
do not have large numbers, so this does not present a major challenge. At an
institution with larger numbers of transfer students, this would be a much
larger problem.
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THE BOTTOM LINE
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Overall, we are pleased with our nonsurvey introductory sequence of
courses, and we believe they meet our objectives better than their
predecessors—a two-semester sequence of survey courses. We are not
satisfied, however, with the current means to include organismal biology in
our curriculum, and we will address this shortcoming again in the near future.
It is impossible to determine the relative contributions by the structure of
the courses versus the small class sizes to the apparent success (student
satisfaction, faculty satisfaction, student success in post-Pomona
biology-related endeavors) of the curriculum. Undoubtedly, both are important.
What we particularly like are the increased level of student engagement with
the material in the courses, the opportunity to emphasize the processes of
"doing biology" in both class and lab, the increased depth of
coverage of the topics in the courses, and the closer relationship that
develops between teachers and students.
TOP
OUR MOTIVATION
THE COURSES