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Spring 2010
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catalyst
AMERICAN UNIVERSITY SCIENCE
College of Arts and Sciences
American University
4400 Massachusetts Avenue, NW
Washington, DC 20016
www.american.edu/cas
UP 11-149 American University is an equal opportunity, affirmative action university.
SCIENCE ISSUES—Darwin on Our Minds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inside cover
Rat Neuroscience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Burrowing into the Depths of Addiction
Science and Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
From the Chemistry Department to Capitol Hill
There is Grandeur in This View of Life (Part I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Evolution Science at AU
There is Grandeur in This View of Life (Part II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
The AU Survey
Postbaccalaureate Pre-Health Students . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
An Important Part of the AU Community
Invasion of the Cnidaria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Understanding Patterns of Distribution of Hydrozoan Jellyfish
Cool Science Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inside back cover
Catalyst Spring 2010 1
`
By Aleksandra Leszczynska,
international studies ’13
Katie Marks grabs the giant rat by the belly
and swings him back and forth as she
prepares to pose for her picture. I lift my
brow skeptically. “It relaxes him,” she notes,
with composure.
Here is a lab of 70 cocaine-drugged rats. Now,
imagine the task of daily vermin feeding, water
filling, and cage cleaning. “Yes, there is really
some inglorious grunt work involved,” says
Katie Marks, a second-year master’s degree
candidate in psychology (and one who does
the dirty work, too).
Yet, all goes in the great name of science. In
Marks’s case, the chores are part of a quest
to understand the workings of the brain. With
her 70 rats (and one pet companion named
Hanson; think Mmbop), Marks is researching
the cognitive deficits associated with addiction.
Marks has done other research, too, recently
winning an honorable mention for the National
Science Foundation’s Graduate Research
Fellowship Program. She scored in the 86th
percentile for her neurocomputational model
of drug addiction, in which she researched
and disputed a previous model of a subject’s
skewed ability to learn the actual value
of reward in addiction, based on overexpectation, and dopamine and chemical
changes in the brain.
The National Science Foundation award is
an honor and a phenomenal achievement
for Marks. At Murray State University in
Murray, Kentucky, where she graduated as a
psychology major and biology minor, Marks
had been intrigued by clinical neuropsychology
and planned work treating traumatic brain
injuries and neurodegenerative disorders.
What brought her to do research within
neuroscience in the first place?
“I am most fascinated with biology and the
physiology of how things work,” she said.
“I come from a family of engineers and I’m
interested in mechanics. And so, I became
fascinated with psychology and the exploration
of the human mind, but I wanted to understand
the biological basis of behavior, as opposed to
doing more theoretical research.” Marks notes,
however, there is not much that is concrete
about neuroscience, either.
After arriving at American University in
2008, Marks took a course on addiction with
Professor David Kearns and became intrigued
by the topic. She soon got involved with the
research lab. A year and a half later, she is
highly invested in addiction studies.
Her latest research, on impulsivity and the
chronic effects of cocaine, explores how the
brain changes after extended access to the
Catalyst Spring 2010 2
drug. Marks’s research focuses on a key
question: after a person ingests cocaine, what
happens to the brain in behavioral issues of
impulsivity, aggression, and social behavior?
Marks uses the rat animal model and she
hopes for the experiments’ results to shed
light on human addiction behavior: “At first I
was pretty skeptical . . . I thought there might
not even be an animal model of addiction; I
thought maybe it was only possible to monitor
in humans. But, we actually can model the
addiction pretty closely using rats.”
So what does the process look like? “We put
the rat in a little box, and there’s a lever he
can push—when he pushes the lever, he can
give himself a dose of drug,” Marks explains.
“It’s completely out of my hands how much
he takes.” With this self-administering model,
Marks and her lab team can manipulate
multiple parameters; for example, they can
integrate stimulus cues—such as turning on
a light that allows the rat to take the drug, or
playing a sound every time it presses the lever
to receive the drug. “So, he learns that the
sound means drug. And the question is, when
you take away the drug, what does the sound
cue do to him? Will he continue responding
to the sound? If you expose an abstinent rat
to that cue later on, will he redevelop that
cocaine addiction?”
Marks’s research is fully funded through
Professor Stan Weiss and David Kearns’
National Institutes of Health R01 grant (NIH’s
largest and most competitive award), and she
highly praises her experience at American
University. “It is incredible to get so much
support, for these professors to trust and
respect me so much,” she says. “I have
really enjoyed being at American. I love the
psychology community that I am in and I have
Photo by Andrew Frank
BURROWING INTO THE DEPTHS
OF ADDICTION: RAT NEUROSCIENCE
Marks, with her comprehensive psychology
foundation, explains that she came into
the addiction world with what she terms
a “more cognitive background.” “See, I
was thinking that addiction was [based on]
mainly thoughts and behavior—and really,
I was even considering the 12-step model
of spiritual malady approach. [The model
developed by Alcoholics Anonymous and
also used by other groups, such as Narcotics
Anonymous.] But, my findings have really
been eye-opening.” According to Marks, the
most surprising elements of the research have
been tracking the data, discovering the extent
to which addiction is biologically based, and
how in some cases behavior can even be
precisely predicted and modified. For example,
every time she places a rat on a schedule of
reinforcement of cocaine, the lab can predict
and graph with a high degree of accuracy the
subject’s behavior—how long it’s going to
take the rat to acquire the drug, how much it
will take that day, how stable it will be after
it is on the drug. Every day Marks and her
colleagues determine points of consolidation,
theorize, and put together new research
ideas to further the study. “There are rules to
prediction; the behavior follows a pattern.”
Katie Marks
been mentored strongly and embraced by
the professors.”
And her future plans and research? Marks
glows as she exclaims, “Well, I hope to
find the cure to addiction! Addiction is just
a fascinating world; it absolutely plagues
our nation and there really seems there’s
Catalyst Spring 2010 3
a biological basis to that that needs to be
discovered. I really want to be part of giving
someone some help, hope, and relief—I just
hope to contribute a little piece of something
to understanding this issue.”
SCIENCE AND POLICY—
FROM THE CHEMISTRY DEPARTMENT TO CAPITOL HILL
By Jordan Maidman, History ’11
Photo by Jordan Maidman
Policy. It’s the focus of many students at AU.
To people studying within the School of Public
Administration, this subject is animated and
dynamic. However, for American University
science majors interested in policy, the State
Department offers more than just politics. In
fact, a significant part of the department’s job
regards American environmental policy away
from mainstream politics.
James Girard, chair of the Chemistry
Department in AU’s College of Arts and
Sciences, embodies this broader role. As
a Franklin Fellow, his job is to coordinate a
report for the entire country regarding waste,
mining, and sustainable consumption and
production. Soon, he will have presented
his findings in Geneva, and afterward, at the
United Nations in New York City.
“Every two years, all UN countries submit
reports on sustainability and consumption,”
Girard says. As coordinator for this year, Girard
works with agencies around Washington,
D.C., ranging from the Environmental
Protection Agency to the Departments of
Labor and Defense. After the presentation
at UN headquarters in New York City, his
recommendation on how to proceed will reach
the halls of the U.S. Capitol, where elected
officials can enact them into law.
Throughout the past 20 years, sustainability
James Girard
and consumption have been two of the leading
issues in the United States. Most climate
change proponents argue that the United
States is lagging behind Western Europe in
sustainability. However, Girard’s research
shows that, “we are way ahead of most of
the Western world,” he says. “I’ve seen some
of the other countries’ reports, and am very
pleased with ours.”
However, the United States is far from perfect.
With regards to consumption, Girard says the
Catalyst Spring 2010 4
country is “crawling, but at least making some
progress.” He believes the best way to fix
this is through local action and environmental
knowledge. “An educated consumer is the
best consumer,” he says. U.S. citizens who
drive hybrid cars, for example, are leading
the struggle to consume less — their cars
use lithium batteries, a salient technology
renowned for energy efficiency. Unfortunately,
lithium is found in only a few places
throughout the world, “one of which [Bolivia]
is not so friendly with us, and if we’re going
As Girard points out, there is still much more
we as consumers can do to help reduce
consumption. The change in consumption
patterns starts on a small scale. “If people
knew how much electricity their appliances
used, they would probably be extremely
surprised,” he says. Consumers buying
appliances in the near future should make sure
they get an energy-star certified machine. The
higher price is easily mitigated by the amount
of money saved in the electricity required to
run it. But Girard recognizes that change costs
money, and if industry is going to lose profits
to become more environmentally conscious,
it will resist. The best way to combat this
resistance is to “either find a cheaper way to
produce these machines, or give a government
subsidy for it.”
But this change will not come easily, and it
must start with us students. If you have a
laptop computer, know where your batteries go
when they die. “I called up Dell to deal with a
leaky battery, and asked the guy who picked
up how they were recycled,” Girard says. “He
said they just throw them out.” That's the sort
of problem Girard faces every day. With all the
chemicals they contain, these laptop batteries
are ticking environmental time bombs. When
batteries just get thrown out, all the interior
components can leak. If those hazardous
components accumulate in the water, they
can cause immense problems for people and
surrounding wildlife, from cancer caused by
metallic agents to the destruction of a forest.
Photo by Andrew Frank
to go to an entire society only using lithium
batteries, we’re going to need a heckuva lot of
it," Girard notes.
Other countries have far more developed
programs for the disposal of batteries. In
Germany, for instance, “they require you
to pay a battery tax. You use it up, take it
back, and recoup the deposit,” Girard says.
Americans already have a similar program with
our plastic bottles. As for recycling batteries in
the United States, they can be returned to the
manufacturer, which can heat them up, flush
out the chemicals, reconstitute them, and get
a fresh new battery that works just as well as
the original. Unfortunately, it’s an expensive
process, but that’s where ordinary people
and the government step in. “We have to put
pressure on these companies to make change
happen. It may require government subsidies,
or maybe just a general boycott of the product
until a new, more environmentally conscious,
solution is implemented,” Girard says.
Catalyst Spring 2010 5
As students, we have a responsibility to take
care of our planet, making Girard’s job a little
easier. Turn your lights off when you’re not
in your rooms. Shut your computers down at
night or put them on hibernate. Don’t leave
every single appliance you own plugged
in all the time. Take the ideas that Girard is
researching and advocating, and implement
them into your lives. Real change requires
effort; small measures like these accumulate
when more people act, and that’s the real
change Girard wants.
THERE IS GRANDEUR
IN THIS VIEW OF LIFE (PART I) . . .
developmental biology and its applications
in evolutionary studies. In stressing the
significance of studying evolution, Angelini
gives the examples of drug resistance
in medicine and pesticide resistance in
agriculture. “Studying evolution is important
for our understanding of the world we live in,”
he says.
EVOLUTION SCIENCE AT AU
Evolution is arguably the most important
concept in biology. It unified the biological
sciences and provided the common ground
for scientists interested in such various
phenomena as heredity, development, and
behavior. Common ancestry and change over
time—or, in Darwin’s own words, descent
with modification—is the axiom, the central
principle of biology. Yet, evolution is not
without its own difficulties, contradictions,
and unknowns. There is much left to be
uncovered and explained. And that makes
evolution a rich field of inquiry and active
research. Let’s take a look at American
University’s own faculty to get a glimpse on
the exciting research that’s being done in the
evolutionary science and how it’s translated
into teaching material for students.
Professor David Angelini of the Department
of Biology is interested in the diversity of
life. Insect life, in particular. It is fascinating
to him, for example, that there exist about
350,000 species of beetles. How are they
different? Angelini is looking for an answer.
However, his research interest is not simply
in the morphological differences of insects,
but rather in the genetic mechanisms that
underlie the development of the morphological
diversity. “I’m interested in how animals
put themselves together,” says Angelini.
For example, the research that he conducts
in his lab focuses on what gene wingless
does in the fruit fly (which is a common
animal model used in genetics). Biologists
are known for their propensity to give genes
names for the lack of the particular gene’s
function. Thus, as the name suggests, the
gene wingless is responsible, among other
things, for development of wings, and when
the function is lost, for instance due to a
mutation, the result is the failure to develop
normal wings. It turns out that in the fruit
fly this gene helps make body segments and
specifies the three-dimensional axes of the
legs of the fly. His next question is: “What is
wingless doing in milkweed bugs in which it
is also found?” This question makes sense
to an evolutionist, who recognizes that the
two species share a common ancestor,
however distant. His research shows that in
milkweed bugs wingless is also responsible
for body segmentation, but, unlike in fruit flies,
knock-out of this gene (i.e., making this gene
inoperative) does not impair development of
normal legs. This suggests that wingless was
probably present in their common ancestor
and that over evolutionary time it assumed
slightly different functions in these species
(development of legs in one but not the other)
Photo source: Library of Congress
By Andrey Verendeev, psychology graduate student
Charles Darwin
while retaining other functions (e.g., body
segmentation). Why would one be interested
in this? Because that’s what evolution is.
Says Angelini, “It’s hard to watch evolution
in real time. But knowing what genes do in
existing species might tell us what happened
in evolution.”
Combining his interest in evolution and
development, Angelini teaches courses on
Evolution has also proved to be essential
in studies of behavior. For most of the past
century, psychologists have emphasized
the importance of learning, both Pavlovian
classical and Skinnerian operant conditioning.
Little attention was paid to the biology
of organisms whose behavior was being
studied. However, within the last 40 years
or so, a revolution took place in psychology.
Biological makeup and evolutionary history of
species have been recognized to put certain
constraints on learning. Professors Alan
Silberberg and Tony Riley of the Department
of Psychology, who both have been teaching
at AU for more than 30 years, witnessed this
development. “There was a movement away
from the solely environmental perspective
on the control of behavior,” says Silberberg.
“It became apparent that behavior, like
body structure, can be a consequence of
evolutionary forces.” Consequently, Silberberg
teaches classes on the evolution of behavior,
in which he discusses “how behavior of
animals is honed by evolution.”
Riley, chair of the department, who received
his initial training in the classical learning
theory, never heard of evolution or Darwin
until he took his first evolution class on a dare.
“I was bewildered,” says Riley. “By the end
of that class I was an evolutionist.” Indeed,
his later choice of graduate school was
much influenced by that class he took as an
undergraduate. At AU, Riley is the director of
the psychopharmacology laboratory and his
research focuses on taste aversion learning,
which is a good example of how evolution
shapes learning in animals. Taste aversion
learning, which occurs when an animal
associates taste with the gastrointestinal
distress, is stimulus-specific and can occur
over long delays, which is inconsistent with
the traditional learning theory but makes good
sense in the natural setting of the animal
allowing for the usual time-course of the
digestive function. “Evolution has remained
a passion and a hobby,” says Riley, who
also teaches a graduate seminar on the
development—evolution, so to speak—of
evolutionary thought. “You have to understand
evolution to understand the phenomenon of
life,” says Riley.
THERE IS GRANDEUR IN THIS
VIEW OF LIFE (PART II) . . .
THE AU SURVEY
By Andrey Verendeev, psychology graduate student
Do you believe in the theory of evolution,
not believe in evolution, or have no opinion
either way? This was the question a sample
of Americans was asked last year on the
eve of the 200th anniversary of Charles
Darwin’s birth. Thirty-nine percent said they
believed in evolution, 25 percent said no, and
the rest (36 percent) had no opinion. This
might sound encouraging, but one should
be cautious, given that the previous year 44
percent of surveyed Americans thought that
“God created human beings pretty much in
their present form at one time within the last
10,000 years or so.” The year 2009, apart
from being the bicentennial year of Darwin’s
birth, also marked the 150th anniversary of
the publication of On the Origin of Species, a
fact that did not escape the attention of various
scientific societies and individual scientists
and nonscientists alike. Most notably, Richard
Dawkins published yet another book on
evolution, which he entertainingly named
The Greatest Show on Earth and in which he
outlined the evidence for evolution. The book
is addressed to that portion of the American
and European public that continues to deny
the evidence for evolution, the history-deniers,
as he calls them. Another noteworthy book
written on the same subject is Jerry Coyne’s
Why Evolution is True. The journal Science ran
a series of monthly essays celebrating Darwin
and evolution. And National Geographic
produced a movie titled Darwin's Darkest
Hour, which describes the publication of On
the Origin of Species.
(continued on next page)
Catalyst Spring 2010 6
Catalyst Spring 2010 7
(continued from previous page)
POSTBACCALAUREATE PRE-HEALTH STUDENTS:
AN IMPORTANT PART OF THE AMERICAN UNIVERSITY COMMUNITY
By Zachary David Skaggs, premedical postbaccalaureate
Despite evolution’s virtually unanimous
acceptance in the scientific community,
recent developments show (for example,
the Kitzmiller vs. Dover Area School District
case) that the nonscientific “theory” of
Intelligent Design has made claims for equal
time in biology classes, a situation analogous
to requiring the teaching of alchemy in a
chemistry classes. This seems to threaten
both the integrity of high school science
classes and, eventually, the readiness of
students to engage in scientific inquiry in
university settings where the subject is given
its full credit. Polls also show that only 21
percent of Americans with a high school
degree accept evolution. This number rises
to 53 percent for college graduates and
74 percent for postgraduates. Thus, it was
naturally interesting to me to learn about
the state of affairs at American University.
In order to learn what attitudes students
at AU had on evolution, I asked three
different questions about the subject: on the
evolution of life, on the evolution of humans
beings, and on the theory of evolution
developed by Darwin. The informal AU poll
had approximately 260 answers in return
(both from undergraduate and graduate
students) and a 6 percent margin of error.
Encouragingly, the majority of AU students
accept the idea that “life evolved over millions
of years from less advanced forms,” with only
about 7 percent answering in the negative.
The number of students who disagree with
this statement falls to 5 percent when “human
beings” is substituted for “life.” (See charts.)
This is surprising, given the idea that humans
share a common ancestor with apes seems
particularly distressing to some people. Finally,
when asked about the theory of evolution as
proposed by Charles Darwin, some 81 percent
thought it was well supported by evidence.
Overall, these numbers seem reassuring and
are consistent with the general polls that
show that the number of people accepting
evolution increases to a majority on university
campuses. It is impossible to say, however,
whether AU students learn about evolution as
part of the university curriculum or whether
they come to AU already educated about
the subject. The Department of Biology, for
example, offers both undergraduate (e.g.,
The Case for Evolution) and graduate (e.g.,
Evolutionary Mechanisms) courses on the
subject. The Department of Psychology also
has something to offer: undergraduate and
graduate classes and seminars that teach
students about evolution and its importance
in studies of behavior (e.g., The Evolution of
Behavior; Evolution of Evolution).
A philosopher once called evolution by
means of natural selection the greatest idea in
science. The theory of evolution has been so
well supported that it is on par with the theory
of gravity as far as scientific certainty goes.
The great geneticist Dobzhansky once said that
“nothing in biology makes sense except in the
light of evolution.” Undoubtedly, we have made
great progress in our understanding of life. But
the fact is, there are many people who deny
evolution in light of all the evidence available
or who have never even heard of evolution. It
took humankind several centuries to accept
the idea that Earth and other planets revolve
around the sun and not vice versa. Let’s hope
it will not take us that long to accept the fact
that we evolved over millions of years and
share common ancestry with all of life.
Though not your usual premed, Clark is far
from alone on campus. Many others have
recognized, after completing a humanities
degree, that their true calling is medicine—or
some related health field. There are currently
47 such “postbaccalaureate pre-health
students” at American University, enrolled
in courses such as organic chemistry and
physics that are required by medical, dental,
and veterinary schools across the country.
Lynne Arneson, adjunct professor of biology
in American University’s College of Arts
and Sciences, oversees postbaccalaureate
students in her capacity as premedical
programs coordinator. Describing her
advising role as her “primary focus,”
Arneson maintains that the life experience
postbaccalaureate students have
accumulated serves them well in navigating
the difficult path to medical school.
Photo by Andrew Frank
Elspeth Clark isn’t your typical premed.
She has already received her degree—in
linguistics from Cornell—and she’s spent
the past two years in Japan teaching English.
Yet the 27-year-old Clark currently finds
herself taking undergraduate cell biology and
biochemistry here at American University—
not to mention acting as a general chemistry
laboratory teaching assistant and volunteering
at Children’s National Medical Center—as
she works toward a career as a physician.
Lynne Arneson
Nonetheless, Arneson, who took over as
premedical programs coordinator in 2009,
personally provides a wealth of support
services for postbaccalaureate students
to help them along the way. In addition to
overseeing the creation of a committee letter
in support of each postbaccalaureate’s
application (“it turns the applicant from a
GPA and MCAT score into a living, breathing,
3-D person”), Arneson organizes healthrelated volunteer work; publishes a premed
newsletter, the Annual Checkup; enforces
application deadlines; and requires students
to attend mock interviews. “We keep track
of the administrative details so students can
focus on their studies,” says Arneson.
“I chose the American University
Postbaccalaureate Program because I wanted
structure and advising as I completed my
premed requirements,” says Adriana Ponce,
an ’08 graduate of Loyola Marymount
University, where she double-majored in
art history and political science. Ponce,
who appreciates the personal attention
she gets from her professors at American
University, also values the fact that “Dr.
Arneson’s door is always open.” In fact,
(continued on next page)
Catalyst Spring 2010 8
Catalyst Spring 2010 9
(continued from previous page)
Although most postbaccalaureate students
are pursuing human medicine or dentistry,
there are a few who are taking courses in
preparation for a career as a veterinarian.
Stephanie Abrams, an environmental
studies major at Skidmore College, is
one of them. She was struck by the care
and attention with which veterinarians
worked to save the life of her dangerously
ill kitten. She went on to shadow several
veterinarians before deciding to pursue a
veterinary career. While taking physics and
biochemistry at American University, Abrams
plans to volunteer at the National Zoo in
Washington, D.C., next semester. Abrams,
like Ponce, has a father who practices as
a physician—and a mother who practices,
too—but ultimately decided that caring for
animals was where her passion lays.
For all their hard work, Clark and company
have a lot to look forward to. American
University postbaccalaureate students
have gone on to attend some of the
most prestigious medical and pre-health
professional schools in the country. A partial
list of schools at which American University
postbaccalaureates have been accepted
INVASION OF THE CNIDARIA
in the past two years includes George
Washington University School of Medicine, the
University of Colorado Medical College, the
University of Maryland School of Medicine,
Virginia Commonwealth University School of
Medicine, the University of Tennessee Health
Science Center, the National Naval Medical
Center, the Uniform Services University
of Health Sciences, and the University of
Pennsylvania School of Dentistry. For the 2009
application cycle, the American University
Postbaccalaureate Program boasted an
acceptance rate of 85 percent for qualified
applicants, designated as those with a GPA
above 3.3 and MCAT scores above 8 per
section. “I think all of my students deserve
to go to medical school after everything
they’ve been through,” says Arneson.
UNDERSTANDING THE PATTERNS
OF DISTRIBUTION OF HYDROZOAN JELLYFISH
By Gabby LaBove, environmental studies, '13
Few people are willing to wake up in the wee
hours of the morning to drive hours away to
collect samples of minuscule jellyfish in fivefoot swells. But this early morning ritual has
become routine for Genelle Harrison, a graduate
student finishing her master’s degree in biology
at American University.
Photo by Genelle Harrison
While contemplating a career as a lawyer,
Ponce ultimately decided on medicine
after consulting with her family. Her father,
an interventional cardiologist practicing
in Los Angeles, helped her to realize the
joy that comes from caring for patients
in their time of need. Immediately after
graduating, Ponce applied to the American
University Postbaccalaureate Program,
where she is currently taking physics,
upper division biology, and biochemistry
courses. Ponce looks forward to a future
career as a physician, which she views as a
“vocation as opposed to a job”—a calling.
A notable difference between
postbaccalaureate programs and a typical
premed path is that the former occurs on an
accelerated schedule. While a premedical
student takes four years to complete
requirements, a postbaccalaureate student
does it in one or two years. Thus Clark, Ponce,
and Abrams will all be applying in fall 2010 for
matriculation in their chosen health graduate
school in fall 2011. “It’s a rare night that
I’m not studying, grading, or reading,” says
Clark as she prepares for the home stretch.
Harrison works with her two advisors,
Professor Kiho Kim from American University
and Allen Collins from the National Systematic
Laboratory of the National Oceanic and
Atmospheric Administration (NOAA), comparing
the DNA of hydromedusae (a type of jellyfish)
to infer invasive patterns between the
populations of different regions. Harrison has
traveled to estuaries in Louisiana, New Jersey,
South Carolina, Virginia, and Delaware in pursuit
of jellyfish, hydromedusae, and ctenophora
(samples have also been sent to her from
Brazil and San Francisco). These organisms
belong to the phylum Cnidaria, possessing
a characteristic most beachgoers are familiar
with—their sting.
Photo by Andrew Frank
Arneson teaches classes only before 10
a.m. or after 5 p.m. so that she can maintain
maximum availability for her advisees.
Blackfordia virginica
Harrison has had memorable—and
dangerous—encounters on some of
her jellyfish-collecting adventures. While
spearfishing a few years ago, she was stung
by a Portuguese Man-of-War, a colony of
jellyfish-like polyps and medusae notorious
(continued on next page)
Catalyst Spring 2010 10
Catalyst Spring 2010 11
(continued from previous page)
Although the hydromedusae samples Harrison
collects now are too small to inflict any harm,
it’s apparent that stings don’t scare her.
Harrison's studies began at the Florida Keys
College, where she received her degree in
technical diving and conducted shark research.
She received her BA in human ecology from
the College of the Atlantic in Maine. By the
time she began studying at AU two years
ago, she had worked with NOAA and Mote
marine lab in the Florida Keys on coral disease,
filmed a documentary on coral spawning, and
received a fellowship from NASA to work on
monitoring protocols for invasive species in
intertidal zones. After graduation, she was
offered a fellowship in Fort Pierce, Florida, at
the Smithsonian’s Marine Field Station studying
the biochemistry and genetics of marine
cyanobacteria (small photosynthetic bacteria).
This research was published in the Journal of
Applied Environmental Microbiology and was
followed with a job offer at the Smithsonian’s
Laboratory of Analytical Biology.
Funding from the Smithsonian Institution
and a Hemlinge Award has allowed Harrison
to begin her research on hydromedusae,
dividing her time between the Smithsonian’s
Laboratory of Analytical Biology and Kim’s
lab. Harrison compares the DNA of her
samples from one geographic region to
samples from other geographic regions. For
example, genes from an organism collected
in Virginia will be compared to organisms
collected in San Francisco to try and find
invasive patterns between the populations of
different regions. “The goal,” Harrison says, “
is to see if you can apply phylogeography to
understand the movement of invasive species.”
Phylogeography considers the geographic
distribution of populations to determine their
evolutionary history.
How does this work? Assume, for example,
there are three jellyfish DNA samples—one
from Delaware, another from New Jersey, and
the last from Maryland. A genetic comparison
shows that the samples from Delaware and
New Jersey are the most similar. Therefore, you
can deduce that the jellyfish frequently move
between Delaware and New Jersey.
In terms of Harrison's work, populations of
jellyfish that move between estuaries will
have higher genetic variation because they
are interbreeding with one another, while
isolated populations will be more genetically
similar because there is less biodiversity. After
extracting DNA from the samples, Harrison
uses polymerase chain reaction (PCR) to
compare the genetic differences between the
hydromedusae. PCR is a technique used to
amplify a specific genetic sequence millions of
times to use the DNA for further sequencing
and comparison.
Three mitochondrial genes and two nuclear
genes are targeted in this study. Mitochondrial
genes tend to evolve faster than nuclear genes,
which is vital to the progress of her research.
While the first introduction of hydromedusae to
Photo by Genelle Harrison
for their vicious venom. Her arm turned black
and she needed medical treatment, which she
never received. Instead, she continued fishing.
Harrison shakes the injury off as if it were a
normal occurrence, which, from the perspective
of a jellyfish collector, is relatively common. “I
thought I was going to have a cool scar, but no
such luck,” Harrison said.
Nemopsis bachei
the Americas is ambiguous, however, scientists
know that they were first described in the late
1800s. Therefore, Harrison must use genes
that evolved quickly (100 years is a very short
period of time in evolutionary history) to find
genetic changes between hydromedusae in
different geographic regions. This will ultimately
show whether or not the populations are
isolated or freely moving between regions.
Trying to find genes that evolve at different
rates is still experimental in cnidarians, and
there is no comprehensive answer to finding
the appropriate genes to answer a specific
question. Therefore, using both nuclear and
mitochondrial genes plays an essential role
in the research because they evolve at
different rates.
This could provide alternative interpretations
of the hydromedusae population’s genetic
patterns. But if an overlap exists, the genes
could also reinforce commonalities between the
populations.
(continued on inside back cover)
Catalyst Spring 2010 12
EDITORIAL
Science Issues—Darwin on Our Minds
The presidential election of 2008 was an explosive year for politics and ideologies. Obama's first year
in office saw the rise of the health-care reform debate and renewed party politics, which put sensitive
scientific issues in the forefront in the American living room once again. The ban on stem cell research
Mission Statement:
A catalyst, as defined by scientists, facilitates chemical
reactions by bringing together substances that might not
interact in its absence. Similarly, Catalyst is one place
where all the sciences come together to relay exciting
was lifted and a renewed push for a greater space exploration budget is currently taking place. In the
scientific developments happening at AU, in the AU
midst of these revolutionary achievements, 2009 was foremost a celebratory year for the sciences.
community, and beyond.
With the 200th anniversary of Charles Darwin's birth in addition to the 150th anniversary of his seminal
classic on evolutionary thought The Origin of Species, 2009 was a year in which all members of the
human race had the chance to ponder the multitude of achievements of one man, his groundbreaking
theories, and the ardent debates he inspired.
Catalyst is a semiannual magazine created to promote
discourse and keep us up to date about how science at
AU affects and inspires us all. Our mission is to: serve
students and faculty in the sciences as a means to
inspire, inform, and promote discourse; share news and
With this in mind, the spring 2010 issue of Catalyst magazine will feature a thought-provoking article
accomplishments of students and faculty; inform students
by graduate student Andrey Verendeev, who surveyed several hundred students at American University
of timely and valuable opportunities; raise the profile of
on their opinions about evolution and contrasted his results to the national statistics on the American
the sciences at AU; and expose students outside of CAS
population's acceptance of Darwin's theories. After reading this issue, perhaps you might find yourself
to exciting science classes.
more intrigued by Darwin's reasoning in the absence of DNA analysis or his doggedness to find a
Our success will be measured by how useful and
solution to a puzzling intellectual problem. Maybe his detailed qualitative observations or his unceasing
informative you find this publication. So we want
curiosity in the world around him from mollusks to finches will inspire you in your own scientific
to hear from you!
endeavors.
Editors:
Whatever your thoughts on Darwin, natural selection, and creationism, this year will again witness a
reunion of human thought and scholarly discussion among those who unfailingly accept Darwin, those
who unequivocally reject him, and the spectrum of beliefs that lies in between. As students, we can
Shirin Karimi, literature and premedical studies ’11
Andrew Frank, biology and environmental science '11
catalyst.au@gmail.com
reflect on this year in humble appreciation of a young man whose stubborn refusal to commit to his
Faculty Advisor:
academics led to an impulsive journey on the HMS Beagle and a subsequent lifelong fascination for
Christopher Tudge
science and progress, a fascination that ignites passion even today.
ctudge@american.edu
Shirin Karimi, coeditor
Please submit letters to the editor to catalyst.au@gmail.com.
“The Hot Spot for Science Education”
Catalyst is published semiannually by the
Catalyst is supported in part through generous donations from alumni and friends of the College of Arts and Sciences.
College of Arts and Sciences
American University
If you wish to make a donation online, go to giving.american.edu. Select Make a Gift and choose the College of Arts and
4400 Massachusetts Avenue, NW
Sciences under Area of Benefit, then fill in the amount of your donation. At the Designation/In honor of window, key in Catalyst
Washington, DC 20016
magazine. Thank you.
www.american.edu/cas/catalyst
ON THE COVER
Inspired by the film Ace Ventura: Pet Detective, the cover features Professor Philip Johnson of the College of Arts and
Sciences' Department of Physics. Photo by Jeff Watts.
INVASION OF THE CNIDARIA
(continued from previous page)
Harrison shared one situation in which
her research has led to new discoveries
in her field. When collecting samples in
Lake Ponchartain, Louisiana, Harrison
found several blackfordia medusae. Its
scientific name, Blackfordia virginica,
explains why this was so strange.
Normally, this cnidarian is found in
Virginia. “No one had reported it there
before I found it this summer,” Harrison
said. But what makes the situation even
stranger is that there has been very little
genetic diversity within populations in
the geographic region. Normally, low
genetic diversity corresponds to isolated
populations, which contradicts the initial
presence of blackfordia in Louisiana.
Instead, this may mean only a few
individuals were introduced and have
begun to populate the estuary. But what
accounts for this movement between
regions? “Every answer raises 20 more
questions,” Harrison says.
While it is generally assumed that the
hydromedusae samples are invasive,
Harrison hopes her research will
provide information on monitoring the
movements of the cnidarians. It is
important to know where the organisms
are being introduced, where they
are spreading to, and their degree of
genetic diversity. When these results are
documented, management protocols can
be created to protect local zooplankton
populations upon which these organisms
feed. However, once an invasive species
has been introduced, it is incredibly hard
to eradicate.
COOL SCIENCE CLASSES
Student: Alisa Morse, film and media arts, ’11
Class: General Chemistry I: Professor Douglas Fox
Catalyst: What was your impression of the class
before you started attending?
concepts; it was applying them to create something.
I enjoyed the hands-on learning.
Alisa Morse: I knew it was going to be a lot of
lecture and independent studying. I was pretty sure
that it was going to be one of the more difficult
classes I would take at AU. At first I was intimidated
because I had taken chemistry in high school, and
I knew some of it would be review, and there would
be difficult components in the lab section. I was a
little intimated too by the fact that I would be in a
class with premed students and students who were
going to use chemistry in their profession. But I
knew I had good background knowledge, but was
expecting it to be hard.
Catalyst: What was your least favorite part of the
class?
Catalyst: Talk about some of the subjects you
covered in class.
AM: General Chemistry I covered all the basics:
nomenclature, stoichiometry, and structures.
General Chemistry did a great job functioning as an
introductory course.
Catalyst: Did you find the class to be more difficult
than other humanities classes?
AM: I did—mostly because mathematics and
chemistry were not my strong point. For me,
chemistry was more difficult because my mind
wasn’t mathematically inclined or chemistry
inclined, so I found it more difficult because the
logic didn’t always make sense to me, once I got
into higher levels. I also don’t memorize well!
Catalyst: What was your favorite part of the class?
AM: My favorite part of General Chemistry was the
lab section. I was actually able to put into practice
things I learned in class. It was not just writing down
AM: Stoichiometry was one of my least favorite
sections of the class but it is imperative. You need to
know it to do anything in chemistry.
Catalyst: Have you seen benefits from taking
General Chemistry?
AM: It’s kind of tricky because the benefits are
huge for people who have the sciences as their
major. As a film major, it’s a bit harder to explain.
The process of going through things that I learned,
especially problem solving, has helped me on a
film set. If I hadn’t taken a class like chemistry, I
probably wouldn’t have been able to solve some of
those problems. The basic knowledge of sciences
enriches my collegiate learning—it’s allowed me the
opportunity to go beyond the arts and allowed me
to realize there are so many things that go into the
mechanics of filmmaking and the technical aspects
of it.
Catalyst: Would you recommend this class to
anyone else seeking a science-related general
education class?
AM: I’d recommend it to anyone who wants a
deeper understanding of things that make up the
world around you and what causes neo-lighting and
other mechanics—it’s doable for anyone, especially
the way it’s taught at AU—it’s amazing where you’ll
find chemistry in your daily life. In photography
class there’s a huge amount of chemistry involved,
and even in filmmaking.
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