Thursday, August 7, 2008: 1:30 PM-5:00 PM
104 B, Midwest Airlines Center
SYMP 21 - Environmental Fluctuation, Temporal Dynamics, and Community Processes
It is increasingly evident that adaptation to the frequencies, and not simply extremes, of environmental fluctuation can regulate the abundances of populations and thus the structure and processes of communities. In plants, temporal niche dynamics induced by non-catastrophic environmental fluctuation have been invoked as a regulatory agent in habitats as widely differing as desert annual communities, Great Plains grasslands, Mediterranean-type scrubland, and tropical forest trees. Appearance in such a diversity of communities suggests a ubiquitous presence in at least the plant world; the role of plants as mediators between above- and belowground ecological processes provides a potential for carry-on effects between, as well as within, trophic levels. The more commonly invoked mechanisms of niche differentiation pinpoint ways in which different species can coexist when they do different things in a spatial or seasonal context. Alternatively, spatio-temporal dynamics allow coexistence of species segregated in patches created by disturbance or edaphic variation. In contrast, temporal niche dynamics allow stable coexistence of interdigitated species that, by all usual measures, are extremely similar. In temporal dynamics, the population of established (reproductive) individuals is stable over time, with the competitive dynamic played out by seedlings and juveniles to produce recruitment alternating between species over years or decades or even to the extent of a century or more in particularly long-lived taxa. Temporal processes work within the interstices of spatial and spatio-temporal niches to pack multiple species into these more traditionally defined niche compartments. At this time, there are a number of different voices with differing stories of temporal niche dynamics in a range of habitats. Currently, the main division is between the pairwise, focused competition of differential sensitivity niche processes and the diffuse competition of multispecies temporal dynamics. The particular goal of this symposium is to bring together a significant sample of those differing viewpoints to create a public platform that will present a breadth of temporal niche actions. Speakers will present work that is either data-based or that addresses data-based applications of theory, with the intention of anchoring what has previously been seen as difficult theory to real-world systems. Our more general goal is to use this opportunity of direct interaction to begin the hard work of determining the parts of those different views that reflect real differences in process, versus differing manifestations of the same underlying principles.
Organizer:Colleen K. Kelly, University of Oxford
Co-organizer:Gordon A. Fox, University of South Florida
Moderator:Gordon A. Fox, University of South Florida
1:30 PM Introductory Remarks: When environmental fluctuation is not catastrophe
1:45 PMSYMP 21-1Temporal dynamics and species coexistence: Investigating the storage effect
Peter Chesson, University of Arizona, Stephen H. Roxburgh, University of New South Wales and CSIRO Forest Biosciences, Nancy J. Huntly, National Science Foundation, Jose M. Facelli, University of Adelaide - School of Earth and Environmental Sciences
2:10 PMSYMP 21-2Differential sensitivity: Focused competition, phylogenetic relatedness, and community structure
Colleen K. Kelly, University of Oxford, Michael G. Bowler, University of Oxford
2:35 PMSYMP 21-3Comparing the influence of climate variability on coexistence in four semi-arid plant communities
Peter B. Adler, Utah State University, Janneke Hille Ris Lambers, University of Washington, Jonathan M. Levine, UC Santa Barbara
3:00 PM Break
3:10 PMSYMP 21-4Seedling herbivory and the temporal niche
Mick Hanley, University of Plymouth, Rebecca J. Sykes, University of Southampton
3:35 PMSYMP 21-5Flowering phenology shaped by facilitation and competition among plant-pollinator interactions
Akiko Satake, Hokkaido Universiy, Yuuya Tachiki, Kyushu Univerity, Yoh Iwasa, Kyushu Univerity, Jaboury Ghazoul, ETH Zurich
4:00 PMSYMP 21-6Temporal variation in density dependence in an herbaceous community
Norma L. Fowler, University of Texas at Austin, Craig Pease, Vermont Law School
4:25 PM Panel Discussion: Detecting temporal dynamics
4:50 PM Concluding Remarks

See more of Symposium

See more of The 93rd ESA Annual Meeting (August 3 -- August 8, 2008)