The Nature of Ecology
This article was originally published in the May 1999 issue of CLASnotes.
"Ecology" means
different things to different people: "environmentalism" to the idealistic
undergraduate (and most journalists and the public at large), "natural history" to
the avid bird watcher, and "inexpensive" to many university administrators.
It is, of course, none of these. Ecology is an integrative scientific discipline
concerned with the dynamics that result from interactions among organisms and
their environments. The dynamics are defined at a variety of scales (e.g.,
from physiological mechanisms up to community structure, from small-scale experiments
to large-scale patterns, and from short to long-term dynamics), and ecologists,
along with evolutionary biologists, seek to develop theory that organizes and
explains the diversity of life and the patterns that emerge across different
biological systems.
The complexity of nature provides us with endless patterns to explain; complexity, however, is also our affliction. Ecosystems consist of hundreds (if not thousands) of different species. Each species is itself extremely heterogeneous, consisting of individuals that can differ in their ecology (e.g., due to differences in age, size, or genotype) as much as can members of entirely different species. Because ecologists deal with heterogeneous systems, whose dynamics operate at different scales, ecologists must rely on a suite of tools and approaches; we are jacks-of-many-trades and seldom masters of a single technique. We not only often require high-tech tools (GIS, image analysis, laser-ablation ICPMS, DNA sequencing), but also a fleet of field vehicles and access to field laboratories and study sites with restricted public access (lest our equipment and experiments disappear). We also must be strongly quantitative, not only in the way we design experiments and evaluate the relative contributions of different ecological processes, but also in the way we apply statistical and mathematical models to make inferences about ecological dynamics.
My research and teaching programs emphasize the integrative and quantitative nature of ecology. I work in lakes and nearshore marine systems (e.g., the Florida Keys), and my research involves both laboratory and field study, experiments and observation, and real systems as well as mathematical models. My primary area of expertise is in the ecological effects of population "stage-structure." For example, fishes (and most other organisms) grow appreciably in size, and, as a consequence, the nature of their interactions with other species changes dramatically over their life time: largemouth bass compete with bluegill early in their life history but later prey upon them.
My colleagues and I have documented that the dynamics of these structured systems are grossly different than those of unstructured (i.e., homogeneous) systems, upon which most ecological theory is still based. Stage-structure also has implications at larger spatial scales: e.g., my research shows that bluegill, which shift habitats during their life history, couple the dynamics of nearshore (vegetated) habitats and offshore (open-water) habitats, which historically have been studied as if they represented two independent systems.
The implications of population structure are perhaps most compelling in applied settings; indeed, some of the classic "mistakes" in fisheries management have arisen through ignorance of stage-structured dynamics. To that end, Colette St. Mary (Zoology), Jacqueline Wilson (a graduate student in my lab) and I have begun projects looking at stage-structured interactions in marine fishes and the implications for the conservation of these fishes and the design of marine reserves. In this work, and my applied work on the statistical design of impact assessment studies, my first priority is to contribute to the theoretical foundations of the field. Indeed, this primary emphasis on theory (and the secondary emphasis on its application) is what uniquely distinguishes the Zoology (and Botany) Department from other biological programs on UF's campus. We provide the theoretical foundation in ecology and evolutionary biology necessary for the applications emphasized in other departments at UF.
Because of the uniqueness of each ecological setting, few ecological results can be "replicated." Instead, the heterogeneity of results becomes, itself, a template for research. The advancement of general theory lies in well-reasoned, quantitative synthesis that reveals the factors that account for these differences in results. To that end, I have championed the integration of ecological models and meta-analysis (the quantitative and statistical comparison of results from many different studies) as a powerful synthetic tool. I have accomplished much of this work through invitations to join and/or lead working groups sponsored by the National Center for Ecological Analysis and Synthesis (an NSF-sponsored center in Santa Barbara, California), which has culminated in a forthcoming Special Feature in the journal, Ecology. I also emphasize these issues in my graduate course, "Quantitative Methods and Ecological Inference."
If you are interested in learning more about my research and teaching program or the Zoology department in general, I encourage you to check out our Web site—my personal page can be accessed at www.zoo.ufl.edu/osenberg.
Credits
Writer
CLAS ecologist and zoology professor Craig Osenberg
Osenberg co-edited Detecting Ecological Impacts: Concepts and Applications in Coastal Habitats, a rigorous treatment of statistical, conceptual, and administrative issues related to the quantification of human impacts on ecological systems.
