|
Research
Interests
Research in my lab is aimed primarily at understanding the origins
and determinants of biological diversity in the islands of the Pacific.
Hawaii is the perfect place to base this work. This research has
been supported by NSF and other granting agencies and has generated
numerous publications, many in top-ranked journals (e.g., Evolution,
American Naturalist, Molecular Ecology). Non-marine snails (land
and freshwater) are the main focus of the various projects going
on in the lab. They offer many advantages for biodiversity research.
Projects in the lab fall in two general areas, focusing
on 1) origins and determinants of native biodiversity and 2) biology
of invasive species and their impacts on native biodiversity, as
follows.
Determinants
of native biodiversity
The study
of patterns of species diversification is developing rapidly, especially
in an evolutionary context, as a complement to the seminal but over-simplistic
"theory of island biogeography". Historical biogoegraphy
is now at the forefront of evolutionary biology as modern phylogenetic
methodologies are applied to questions of the geographic and evolutionary
origins of biological diversity. My research incorporates both ecological
and evolutionary approaches. Questions I am addressing are: what
ecological factors influence distribution patterns; what determines
numbers of species on particular islands and archipelagos; what
are the geographic and phylogenetic origins of Pacific island land
snails? These issues have become the central core of my research
over the last few years, funded in part by NSF and USGS/BRD, and
have incorporated modern molecular techniques of DNA analysis to
develop phylogenies that are the necessary prerequisites for answering
many of these evolutionary and ecological questions.
Conservation
and alien species
The fascinating diversity that has prompted the above research
is, however, disappearing. Thus, conservation of the unique island
faunas is of crucial importance. I am involved in three main areas
addressing conservation issues, focused not only in Hawaii but covering
the entire insular Pacific.
Invasion
biology
Invasion biology is one of the fastest-growing and important areas
of conservation biology. Much of my recent research has focused
on alien species, and especially on the patterns and processes of
faunal homogenization in Hawaii and throughout the islands of the
Pacific, the specific impacts of certain alien species, and the
worldwide pathways via which they are spread.
Apple snails
Dealing with alien species in general, led me to become involved
more closely with introduced crop-damaging freshwater snails ("apple
snails") in Hawaii and South-East Asia. These highly invasive
snails have the potential to cause enormous ecological damage. This
research is focused on two areas: 1) understanding the dynamics
of the invasions, using the snails as a model to address the underlying
causes of invasiveness; and 2) the systematics, phylogenetic relationships,
and biogeography of the family (Ampullariidae) to which the snails
belong.
Conservation
ecology
One of the most fundamental questions in conservation biology is
why some native species are more vulnerable to extinction (especially
in the face of alien invasions) than others. Ecological characteristics
of the species are obviously important and have prompted much speculation.
Among the native Hawaiian and Pacific snails, some seem less vulnerable
than others to the suite of threats they are faced with. In Hawaii,
the Succineidae are one of the groups seemingly least in decline.
We have begun to investigate reasons for the succineids' relative
immunity to these threats. Questions to be asked include the following.
Why are succineids in Hawaii still abundant? In fact only some of
them are; others seem very rare or gone; why is that? Is life-history
important? How does succineid life-history differ from that of better
known but more precarious species (e.g., Achatinellinae)? What are
succineid habitat and food preferences? Can they survive in non-native
habitat? Probably some of them can-why? What are the food preferences
of the alien predatory snail Euglandina rosea, which is one of the
major scourges of other native Hawaiian and Pacific land snails?
What are its ecological limits? Basic ecological research of this
kind is essential for understanding the potential for conserving
the native species and for directly addressing management options
Representative
Publications
Holland, B.S. &
Cowie, R.H. 2007. A geographic mosaic of passive dispersal: population
structure in the endemic Hawaiian amber snail Succinea caduca (Mighels,
1845). Molecular Ecology 16: 2422-2435.
Rawlings, T.A., Hayes, K.A., Cowie, R.H. & Collins,
T.M. 2007. The identity, distribution, and impacts of non-native
apple snails in the continental United States. BMC Evolutionary
Biology 7: 97 [14 p.] [published on line].
Cowie, R.H. & Holland B.S. 2006. [Guest Editorial]
Dispersal is fundamental to biogeography and the evolution of biodiversity
on oceanic islands. Journal of Biogeography 33: 193-198.
Cowie, R.H. 2004. Disappearing snails and alien
invasions: the biodiversity/conservation interface in the Pacific.
Journal of Conchology Special Publications 3: 23-37.
Lydeard, C., Cowie, R.H., Ponder, W.F., Bogan, A.E.,
Bouchet, P., Clark, S., Cummings, K.S., Frest, T.J., Gargominy,
O., Herbert, D.G., Hershler, R., Perez, K., Roth, B., Seddon, M.,
Strong, E.E. & Thompson, F.G. 2004. The global decline of nonmarine
mollusks. BioScience 54: 321-330.
Rundell, R.J.,
Holland, B.S. & Cowie, R.H. 2004. Molecular phylogeography of the
endemic Hawaiian Succineidae (Gastropoda: Pulmonata). Molecular
Phylogenetics and Evolution 31: 246-255.
Cowie, R.H. & Robinson, A.C. 2003. The decline of native Pacific
island faunas: changes in status of the land snails of Samoa through
the 20th century. Biological Conservation 110: 55-65.
Rundell, R.J. & Cowie, R.H. 2003. Growth and reproduction in Hawaiian
succineid land snails. Journal of Molluscan Studies 69(3):
288-289.
Cowie, R.H. 2002. Invertebrate invasions on Pacific islands and
the replacement of unique native faunas: a synthesis of the land
and freshwater snails. Biological Invasions 3(3)[2001]: 119-136.
Cowie, R.H. 2002. Apple snails (Ampullariidae) as agricultural pests:
their biology, impacts and management. In: Molluscs as Crop Pests
(ed. G.M. Barker), p. 145-192. CABI Publishing, Wallingford.
Cowie, R.H. 2001. Can snails ever be effective and safe biocontrol
agents? International Journal of Pest Management 47: 23-40.
Lach, L., Britton, D.K., Rundell, R.J. & Cowie, R.H. 2001. Food
preference and reproductive plasticity in an invasive freshwater
snail. Biological Invasions 2(4)[2000]: 279-288.
Asami, T., Cowie,
R.H. & Ohbayashi, K. 1998. Evolution of mirror images by sexually
asymmetric mating behavior in hermaphroditic snails. The American
Naturalist 152: 225-236.
Cowie, R.H. 1998. Patterns of introduction of non-indigenous
non-marine snails and slugs in the Hawaiian Islands. Biodiversity
and Conservation 7: 349-368.
Cowie, R.H. 1995. Variation in species diversity
and shell shape in Hawaiian land snails: in situ speciation and
ecological relationships. Evolution 49: 1191-1202.
[return
to top]
|
