Alan Hastings talks with
ScienceWatch.com and answers a few questions about
this month's Emerging Research Front Paper in the field of
Plant & Animal Science.
Article: The spatial spread of invasions: new
developments in theory and evidence
Authors: Hastings, A;Cuddington, K;Davies,
KF;Dugaw, CJ;Elmendorf, S;Freestone, A;Harrison, S;Holland,
M;Lambrinos, J;Malvadkar, U;Melbourne, BA;Moore, K;Taylor,
Journal: ECOL LETT, 8 (1): 91-101 JAN 2005
Addresses: Univ Calif Davis, Dept Environm Sci & Policy,
Davis, CA 95616 USA.
Univ Calif Davis, Dept Environm Sci & Policy, Davis, CA
Univ Calif Davis, Dept Math, Davis, CA 95616 USA.
Why do you think your paper is highly
The issue of spatial spread is central to many areas of ecology, and the
number of invaders spreading spatially throughout the world is increasing.
This is an issue of great applied interest because the cost to control
spreading invasive species is extremely high. For example, many insect
pests are spreading invasive species.
Conversely, the study of invasive species is providing insights into
general issues of ecology. Thus, the paper focuses on a central issue
common to both basic and applied ecology. Since any given invasion is
replicated essentially only once in nature, a synthetic approach can be
very useful in understanding the dynamics of a particular invasion.
Additionally, this is a paper where all 14 authors truly made substantial
contributions. Combining the insights of so many individuals with differing
perspectives produced a paper that is both broader and deeper than any one
individual could create.
Does it describe a new discovery, methodology, or
synthesis of knowledge?
"Future work on understanding other aspects of the
problem of invasive species, including impacts on other
species, will also clearly be important."
The paper focuses on the synthesis of knowledge in the area of the spread
of invading species. By bringing together recent theoretical developments
and empirical observations, we can understand both when simpler ideas can
explain rates of spread and also when underlying heterogeneities must be
Would you summarize the significance of your paper
in layman’s terms?
The paper begins with a review of classic approaches to understanding
spatial spread, which emphasized the simpler aspects of the problem that
would produce a constant rate of spread. More recent work has focused on
the complexities of the problem, such as the role played by long-range
dispersal and underlying heterogeneities. These change the dynamics of
spread in important ways.
How did you become involved in this research and
were any particular problems encountered along the way?
My colleagues and I have been looking at spread both from a general point
of view and also in the context of specific examples, such as the spread of
the cordgrass Spatina alterniflora, crabs, and various insects.
The paper grew out of a desire to combine the knowledge and insights that
came from many of us studying many different invasions from both an
empirical and theoretical viewpoint.
Trying to distill the most important insights, to integrate a vast body of
empirical studies, and to explain the theoretical work in a straightforward
fashion that elucidated how different conclusions depended on different
assumptions were the biggest challenges.
Where do you see your research leading in the
We are conducting research on both general and specific instances of
spread. Additionally, we are carefully working on adding economic
considerations, in order to understand how to design cost-effective methods
Understanding how to make management decisions in the face of limited
knowledge is a critical aspect of future work on invasions, as is extending
insights to include interactions among different species.
Do you foresee any social or political
implications for your research?
The spread of invasive species has very large economic consequences.
Understanding the dynamics of spread is a first step to understanding
potential impacts, and also for planning appropriate management. Future
work on understanding other aspects of the problem of invasive species,
including impacts on other species, will also clearly be important.
Alan Hastings, Ph.D.
Department of Environmental Science and Policy
University of California, Davis
Davis, CA, USA Web |
KEYWORDS: DIFFUSION; DISPERSAL; INTEGRO-DIFFERENCE EQUATIONS; INVASIONS;
REACTION-DIFFUSION; SPATIAL SPREAD; INVADING ORGANISMS; NORTH-AMERICA;
PLANT INVASIONS; DIFFUSION-MODEL; RANGE EXPANSION; HETEROGENEOUS
ENVIRONMENTS; BIOLOGICAL INVASIONS; LINEAR DETERMINACY; LOCAL ADAPTATION;