Experiences in Integrative and Comparative Biology
This installment of "Experiences" is a special one for me. We show here an essay from Dr. John Vernberg, who was the president of our society, then the American Society of Zoologists, in 1982. I first met John when I was a graduate student in the newly formed Marine Science Program at the University of South Carolina. Dr. Winona B. Vernberg was my major advisor and it was this remarkable husband and wife team that inspired all of us to embrace our passion for science and do it with good humor and healthy collaborations. And yes, I came to know and "love" the Gilson Respirometer pictured with the essay.
Lou Burnett, SICB Secretary
John Vernberg
To highlight specific
research experiences from a database of 49 years of pre- and
post-doctoral research endeavor is a daunting task. The research
path leading from submitting a dissertation to retirement was far
from being a straight line! However, there is a common thread which
links the apparent deviations in the direction of the path
represented by my different research projects. A fundamental question
originally stimulated my scientific efforts and it continued
throughout my career: What mechanisms enable an organism to live in
an environment consisting of a complex of interacting abiotic and
biotic factors? My research was not restricted to the study of a
given species but was problem directed. This proved to be an
adaptive opportunistic response by me because outside factors, such
as job location and family, dictated to a degree a new environment to
study with a new set of experimental animals. For example, my
graduate work was done at Purdue University studying the
physiological ecology of salamanders associated with the Ross
Biological Reserve. My first post-graduate "job" was at
Duke University which also had a forested reserve area. However, the
allure of the ocean with a high diversity of organisms and habitats
exerted an overpowering force pulling a Midwesterner to the shore
where the Duke Marine Laboratory is located.
At first I studied the
comparative tissue metabolism of several fish species in relationship
to their locomotor behavior. Perhaps, because I enjoyed the beach, I
took an interest in the intertidal zone. Not only was there an
appealing fauna assemblage, ranging from mammals to micro fauna, but
the rhythmic tidal action exposed organisms to daily aerial and
submerged environmental changes as well as marked seasonal changes.
One way of studying how
animals respond to their environment is to compare the physiological
responses of various species and/or different populations of one
species to various physical and biological factors. A few examples
of the comparative approach will briefly demonstrate this approach.
Dr. Richard Tashian and I began a study on the ecology and physiology
of latitudinally separated species of fiddler crabs, genus Uca
which Dr. Winona Vernberg and I continued. Studies ranged from
determining and comparing functional responses of adults and
developmental stages at both the organismic and tissue/cellular
levels of various species from tropical and temperate zones. In
addition, interspecific competition of species at the area of their
overlapping geographic ranges was conducted to determine the role of
behavior and physiological responses in limiting the distribution of
species. Although our studies predated the current intense interest
in the impact of global warming, the results are relevant. Naturally
it was necessary to study populations of fiddler crabs along the
Atlantic coast from their most northern limits in Massachusetts to
their southern limits in southern Brazil and Argentina. Winona and I
accepted this scientific mandate, after all someone had to do it!
Seriously, we found the experience greatly broadened our thoughts on
ecophysiological phenomena (and to answer the urge to satisfy our
need to honor the creed of the United States Navy "to see the
world" which was instilled in us during our period of service in
World War II).
Our latitudinal studies
expanded to include the offshore fauna when an oceanographic ship
(R/V Eastward) became available. Working at sea on a 120-foot vessel
is a real research experience! Now we could compare metabolic
patterns of species characteristic of colder water north of Cape
Hatteras with that of species inhabiting the warmer waters associated
with the Gulf Stream.
Another bend in our
research path resulted when we focused our attention on the question
of how environmental factors influenced the physiological ecology of
both a parasite (trematodes) and the various hosts that the parasite
inhabits when completing its life cycle.
How does the genome of
an individual animal enable the organism to function in the wide
range of habitats it encounters which may vary from anaerobic to
free-living aerobic and/or cold-blooded to warm-blooded hosts? Also,
what impact does the parasite have on the host? These studies
involved metabolic measurements, determination of survival rates of
intact organisms, and behavioral studies. Unfortunately the
techniques of present day molecular biology and genetics were not
readily available to us during this period of our research careers.
These studies, which
have been described in greater detail in our various publications,
are presented here to demonstrate that our research experiences have
been exciting to us and totally unexpected based on the knowledge of
the environment we had when finishing graduate school. As
technological advances are made, the researcher has an opportunity to
expand his/her horizons and some day to look back and remember the
high points with more clarity than the frustrations.