Robert J. Marquis, Ph.D., University of Iowa
Email: c4833@umslvma.umsl.edu
Selected Publications
- Marquis, R.J. 1988. Phenological variation in the neotropical
understory shrub Piper arieianum: causes and consequences.
Ecology 69:1552-1565.
- Marquis, R.J. 1988. Intercrown variation in leaf herbivory and
seed production in striped maple, Acer pensylvanicum L.
(Aceraceae). Oecologia 77:51-55.
- Marquis, R.J., and G.O. Batzli. 1989. Influence of chemical
factors on palatability of forage to voles. Journal of
Mammology 70:503-511.
- Marquis, R.J., and S. Passoa. 1989. Seasonal diversity and
abundance of the herbivore fauna of striped maple Acer
pensylvanicum L. in western Virginia. American Midland
Naturalist 122:313-320.
- Marquis, R.J. 1990. Genotypic variation in leaf damage in Piper
arieianum (Piperaceae) by a multi-species assemblage of
herbivores. Evolution 44:104-120.
- Marquis, R.J. 1991. Herbivore fauna of Piper (Piperaceae) in a
Costa Rican wet forest: diversity, specificity and impact. In:
Plant-Animal Interactions, Evolutionary Ecology in Tropical and
Temperate Regions,
- P.W. Price, T.M. Lewinsohn, G.W. Fernandes, and W.W. Benson
(eds.). J. Wiley and Sons, pp. 179-208.
- Marquis, R.J. 1991. Evolution of resistance in plants to
herbivores. Evolutionary Trends in Plants 5:23-29.
- Marquis, R.J. 1991. Physiological constraints on response by
Ostrya virginiana (Betulaceae) to localized folivory.
Canadian Journal of Botany 69: 1951-1955.
- Marquis, R.J. 1992. A bite is a bite is a bite? Constraints on
response to folivory in Piper arieianum (Piperaceae).
Ecology 73:143-152.
- Marquis, R.J. 1992. Selective Impact of Herbivores. In: R.S.
Fritz and E.W. Simms (eds.) Ecology and Plant Resistance to
Herbivores and Pathogens. University of Chicago Press, pp.
301-325.
- Marquis, R.J., and H.M. Alexander. 1992. Evolution of resistance
and virulence in plant-herbivore and plant-pathogen
interactions: an integrative approach. Trends in Ecology and
Evolution 7:126-129.
- Marquis, R.J., and H.E. Braker. 1993. Plant/herbivore
interactions at La Selva: Diversity, specialization and impact
on plant populations. In: La Selva: Ecology and Natural
History of a Neotropical Rainforest, L. McDade, G.H. Hartshorn,
H. Hespenheide, and K. Bawa (eds.), University of Chicago
Press, pp. 261-281.
- Frazee, J.E., and R.J. Marquis. 1994. Environmental contribution
to floral traits in Chamaecrista fasciculata (Fabaceae:
Caesalpinoideae). American Journal of Botany 81:206-215.
- Marquis, R.J., and C.J. Whelan. 1994. Insectivorous birds
increase plant growth through their impact on herbivore
communities of white oak. Ecology 75:2007-2014.
- Marquis, R.J., and C.J. Whelan. Plant morphology and recruitment
of the third trophic level: subtle defenses? (in press,
Oikos).
Research Interests
The focus of my research is the ecology and evolution of plant
resistance to herbivores. Specifically, I have begun to elucidate
the factors which promote or constrain evolutionary changes in
plant resistance at the population level. Because herbivores are
considered pests on economically important plant species, and
because plant and herbivore interactions are often mediated by
parasitoids and predators (such as birds), research in this area
often has direct application to management and conservation
issues. When possible, I have designed my research to
incorporate both basic and applied aspects of the questions under
study.
Seasonal and geographic abundance of oak herbivores and their
associated parasitoids.
This is a project associated with an
experiment being conducted by the Missouri Dept. of Conservation
on the impact of various forest management plans on forest
productivity and biodiversity. We are monitoring herbivore
faunas of four oak species on 9 plots in se Missouri four times
during the summer. I was brought into this area of research
after a project looking at the impacts of insectivorous birds on
insect communities on oak, and in turn, the impact of plant
growth. This initial work, mostly natural history, will provide
the basis for more experimental studies in this system, looking
at the combined and interactive impact of plant chemistry,
parasitoids, birds on the herbivore community and subsequent
plant damage.
Response of plant enemies (both fungi and insects) to native
tree plantations in Costa Rica.
This a collaborative project
between four Costa Rican scientists, me and Beth Braker
(Occidental College). We are planting native tree species in
mono- and polycultures in abandoned pasture, early secondary
forest and primary forest to determine: a. how plant density
affects plant enemy population levels, and b. how to best plant
trees in abandoned lowland tropical pastures in order to make
them productive and avoid further destruction of primary forests.
Quantification of plant resistance traits in Piper.
In
collaboration with the phytochemist Kelsey Downum of Florida
International University, I am describing the plant traits and
genetic and environmental impacts on those traits which
contribute to plant resistance. Our goal is to determine the
causes of interaspecific variation in leaf herbivory levels in
Piper arieianum, and thus the potential for various traits of
this plant speciesto evolve in response to selection by its
herbivore species.
Correlates of interspecific variation in leaf damage in
Brazilian cerrado trees.
I have started a collaborative project
with Brazilian scientists to repeat work of P. Coley but in a
different tropical forest system. Our goal is to determine the
main factors which account for interspecific variation in leaf
damage and whether plant life history dictates different defense
regimes. In a followup more focused study, we have chosen one
plant species to determine the combined and separate effects of
pathogen and insect attack on plant fitness.
Population dynamics of a tropical clonal understory
treelet.
This is a longterm collaborative project with Nancy Greig looking
at how clonality may or may not contribute to survival of
understory plant species in the deep shade of a lowland tropical
wet forest.
Graduate Students
- Marie Ann de la Fuente (M.S.) has been measuring interspecific
variation in extrafloral nectar production as affected by
microenvironment, and subsequent influence on the ant community
and plant damage in a tropical tree species in Costa Rica.
- Cris Hochwender (Ph.D) is studying the combined and separate
impact of root, leaf, and seed predators, and pathogens on
fitness of the common milkweed (Aclepias syriaca).
- John Lill (Ph.D.) is studying the role of host plant and
insect enemies in determining life history variation in
oak-feeding insects of Missouri Ozarks.
- Kirk Stowe (Ph.D.) is doing selection experiments with
fast-cycling Brassicas to determine tradeoffs between defense
traits and ability to cope with non-herbivore stresses (water
deficits, for example).
- Eric Wold (M.S.) is studying the interaction between early and
late season herbivore faunas on white oak and the implications
for plant fitness.