Experiences in Integrative and Comparative Biology
SICB members like a good story about an expedition, a field experience, a lab experiment, or another researcher! To spice up our newsletter, I have asked some of the leaders of SICB to relate one or two experiences that might be of interest to the membership. This issue features Ron Dimock, SICB Treasurer and Linda Walters, SICB Program Officer.
Lou Burnett, SICB Secretary
Ron Dimock, SICB Treasurer
I've always really
My fondness for clams
started with Mya arenaria that I consumed in large quantities
from 'clam shacks' in New Hampshire and Maine as a kid. When I
got to college, I had the good fortune to become immersed not only in
clams, but invertebrates at large, in the company of the likes of
George M. Moore, Lorus and Margery Milne, Emory Swan, Art Borror,
Alan G. Lewis and others at the University of New Hampshire. Having
never once considered being pre-med, I saw my career appear before me
during a summer course in the Natural History and Taxonomy of Marine
Invertebrates with Norman Meinkoth, a visiting professor from
Swarthmore. The road trip to Lubec, Maine, Passamaquoddy Bay and the
fringes of the Bay of Fundy, with 30 ft+ tides and a couple cases of
beer shared with 3 traveling companions turned me on to marine
At the urging of Art
Borror, and a growing interest in diving in water other than the Gulf
of Maine, I ended up at Florida State University with Mike Greenberg,
who taught me experimental biology and hooked me with comparative
physiology/integrative biology. A master's thesis that required
only the hearts of oysters enabled my wife and me to eat more
Crassostrea bodies, fixed every way imaginable, than any one
should, so much so that she refused to eat oysters for years after.
With the fauna of the Gulf under my belt (literally), we moved to
Santa Barbara, the tutelage of Demorest Davenport, and the
opportunity to spend a summer at Friday Harbor sharing a lab with
then graduate student, Dennis Willows. The rest, as they say, is
history, ultimately involving 35+ years of teaching invertebrate
biology at Wake Forest University and more than 20 summers teaching
the marine invertebrate course at the Duke Marine Lab on the North
But the salinity of my
blood, and of my clams, was becoming diluted living 5 hrs from the
coast. My fondness for bivalves continued unabated, but unionid
mussels are not the gourmet item of choice. However, they have given
me the better part of a full career, serving first as hosts to
symbiotic water mites and my Davenport-inspired experimental approach
to symbioses, and later to functional morphology, development and
even shades of immunology and molecular biology as my focus shifted
to the host mussels and their bizarre life history. I mean really,
what quirk of intelligent design would house Pac Man-like mussel
larvae in water tubes of mom's gills, to be released to become
temporary parasites on the fins or gills of an unsuspecting fish host
that has been conned into upstream transport and the avoidance of
being a larva swept down to the sea?
Mussels have taken me
from the 1000-year old canals of The Netherlands, complete with
shards of 17th Century clay pipes, and lots of broken
glass, to the Australian Outback where every second living thing is
poisonous or can eat you. Along the way I've had the good fortune
to nudge a number of neophytes along the path to discovery and
satisfaction that has been good to me for nearly 40 years.
A Baker's Dozen
Dimock, R. V., Jr., and J. G. Dimock. 1969. A possible "defense"
response in a commensal polychaete. Veliger 12: 65-68.
Dimock, R. V., Jr., and D. Davenport. 1971. Behavioral specificity
and the induction of host recognition in a symbiotic polychaete.
Biol. Bull. 141: 472-484.
Pruitt, N. L. and R. V. Dimock, Jr. 1979. The effects of temperature
and eyestalk extracts on oxygen consumption of the crayfish Cambarus
acuminatus (Faxon). Comp. Biochem. Physiol. 62A: 631-634.
Dimock, R. V., Jr. 1983. In defense of the
harem: intraspecific aggression by male water mites. Ann. Entomol.
Soc. Am. 76: 463-465.
Dimock, R. V., Jr. and C. Davids. 1985. Spectral sensitivity and
photo-behaviour of the water mite genus Unionicola. J. Exp.
Biol. 119: 349-363.
Tankersley, R. A. and R. V. Dimock, Jr. 1992. Quantitative analysis
of the structure and function of the marsupial gills of the
freshwater mussel Anodonta cataracta. Biol. Bull.
Polhill, J. B., V., and R. V. Dimock, Jr. 1996. Effects of
temperature and pO2 on the heart rate of juvenile and adult
freshwater mussels (Bivalvia: Unionidae). Comp. Biochem. Physiol.
Edwards, D. D. and R. V. Dimock, Jr. 1997. Genetic differentiation
between Unionicola formosa and U. foili
(Acari: Unionicolidae): cryptic species of molluscan symbionts.
Invert. Biol. 116: 124-133.
Schwartz, M. L. and R. V. Dimock, Jr. 2001.
Ultrastructural evidence for nutritional exchange between
brooding unionid mussels and their glochidia larvae. Invert. Biol.
Dimock, R. V., Jr. 2000. Oxygen consumption by juvenile Pyganodon
cataracta (Bivalvia: Unionidae) in response to declining
oxygen tension. pp. 1-8. In, R. A. Tankersley, D. I. Warmolts, G. T.
Watters, B. J. Armatage, P. D. Johnson and R. S. Butler,(editors.
Freshwater Mollusk Symposium Proceedings, Ohio Biological Survey,
Fisher, G. R. and R. V. Dimock, Jr. 2002. Ultrastructure of the
mushroom body: digestion during metamorphosis of Utterbackia
imbecillis (Bivalvia: Unionidae) Invert. Biol. 121: 126-135.
Rogers-Lowery, C. L. and R. V. Dimock, Jr. 2006. Encapsulation
of attached ectoparasitic larvae of freshwater mussels by epithelial
tissue on fins of naive and resistant host fish. Biol. Bull. 210:
Rogers-Lowery, C. L., R. V. Dimock, Jr. and R. E. Kuhn. 2007.
Antibody response of bluegill sunfish during development of acquired
resistance against the larvae of the freshwater mussel Utterbackia
imbecillis Develop. & Comp. Immunol. 31: 143-155.
Linda Walters, SICB Program Officer
When I began my faculty
appointment at the University of Central Florida in Orlando 10 years
ago, I decided that I would use my training in marine ecology to
address both basic and applied questions on how humans are impacting
the coastal environment, especially in Florida. Currently in my lab,
my students and I are looking at how recreational boat wakes are
causing the decline of intertidal oyster reefs and restoration of the
same, ballast water disinfectants, dispersal and DNA forensics of
invasive flora and fauna, and the ecology of coral larvae in situ. I
am presently on sabbatical and decided to spend my year addressing
two questions with marcoalgae that greatly interested me, but I did
not have time to pursue during the regular academic year. I first
spent two months in the St. Thomas at the University of the Virgin
Islands looking at foraging by the long-spined sea urchin Diadema
antillarum from the point of view of the algae. This keystone
herbivore has recently returned to the USVI and other locations in
the Caribbean after a 20+ year absence and resource managers are
eager to learn if this return will mean the end of algal blooms on
coral reefs. My colleagues and I ran simple feeding trials and found
this urchin is a very fussy consumer avoiding many species. With the
avoided species, the urchin usually shreds the biomass, creating many
fragments. These fragments can then attach to substrates and
continue growing as clones. There will have to be a really huge
increase in Diadema numbers to remove all of the unpalatable
macroalgae. From there, I went with my family to Australia for 4
months to look at vegetative fragmentation in the green alga Caulerpa
taxifolia. The invasive form of this macroalgae is listed as one
of the world's 100 worst invasive species. Australia is the only
country where both invasive and native populations of Caulerpa
can be found. I am running lab and field manipulations in New South
Wales (with invasive Caulerpa) and in Moreton Bay in
Queensland (native form) to determine the minimum viable fragment
size. While these experiments are still underway, I can say that
there are many significant differences between the two forms and the
invasive appears much better suited for dispersing, survival and
attachment. University of Queensland's marine lab is on North
Stradbroke Island and is one of the nicest facilities I have had the
pleasure of working at over the past 20 years. Additionally the
island is a wonderful, small community that is very safe, has
incredible sand flats and white sand beaches, and, according to my
10-year old son, has the best gelato on this planet!