 neutral diversity in a metacommunity network (from Economo & Keitt 2010) |
Biodiversity Dynamics in Spatial
Networks Biodiversity pattern and process manifest on levels of organization and spatiotemporal scales. I'm interested in how ecological and evolutionary processes interact in spatially complex landscapes to drive patterns at different levels of the hierarchy. My work has particularly focused on using network theory to represent the structure of geographic space, where nodes are ecological communities and links represent the movement of individuals among them. Over the last several years I have brought neutral theory into in this framework, investigating how the spatial structure of metacommunities drives diversity patterns. Looking forward, I want to understand how different dimensions of biodiversity, from nucleotides to community interaction webs, vary with isolation in a spatial network. This involves developing new theory but ultimately needs to be addressed empirically. Towards that end my colleagues and I are analyzing the biodiversity of two systems at multiple levels along an isolation gradient in the Pacific. The first system is the ants of the Pacific islands, which I describe below. The second is coral reef fish diversity in marine networks, a collaborative project I am pursuing with colleagues at the Field Museum and in Australia. I am also interested in a broader class of problems related to stochastic processes in biological networks, and have pursued some collaborative work in this area on RNA evolution. |
Publications:
|
--Economo, E. P.
(2011)
Biodiversity Conservation in Metacommunity Networks: Linking
Pattern and Persistence. The
American Naturalist. 177
(6) E167-180. PDF. --Leibold, M., Economo, E., Peres-Neto, P. (2010) Metacommunity Phylogenetics: Separating the Roles of Environmental Filters and Historical Biogeography. Ecology Letters. 13 (10) 1290-1299. PDF. --Economo, E. and Keitt, T.H. (2010). Network Isolation and Local Diversity in Neutral Metacommunities. Oikos 119: 1355-1363. PDF. --Economo, E., and Keitt, T.H. (2008). Species diversity in neutral metacommunities: a network approach. Ecology Letters 11(1): 52‐62. PDF --Cowperthwaite, M., Economo, E., Harcombe W., Miller, E., Meyers, L. (2008). The Ascent of the Abundant: How mutational networks constrain evolution. PLoS Computational Biology 4(7): e1000110. PDF |
 Poecilomyrma myrmecodiae. Poecilomyrma is Fiji's only endemic ant genus. New: Timeline of Fiji Ant Research (4.2 MB) |
Biodiversity
and
Biogeography of Pacific Island Ants The Pacific Islands are an amazing island world where thousands of small, isolated terrestrial ecosystems are separated by vast distances. Over millions of years, lineages have dispersed, evolved, and diversified through this network. More recently, humans have introduced a number of exotic species to the islands and these are having dramatic effects on native faunas. These forces combine to assemble the communities of ants we see today on each island. I'm interested in disentangling the processes underlying these patterns with integrative approaches. While ants in this region have been studied for over 100 years, and were the inspiration for E.O. Wilson's seminal work in the development of island biogeography theory, we have found that these island faunas are still remarkably unknown. My colleague, Eli Sarnat, and I have been broadly inventorying ant communities in the Fijian archipelago, and working on a taxonomic reorganization of the fauna. After several years of collecting and curation, our book length monograph detailing and updating the the fauna is now submitted. We are using these data to re-examine Wilson's ideas about the taxon cycle and patterns of community assembly. We also have compiled a thorough dataset on ant distributions across the Pacific, and are analyzing macroecological patterns of the native and invasive species. Looking forward, we are self-organizing with other Pacific myrmecologists to 1) develop and disseminate basic biodiversity data, species lists, etc., 2) use molecular approaches to reveal the evolutionary history of these island lineages and communities, 3) understand how ecological dynamics on a plot scale affect and are affected by biodiversity dynamics on a large scale, and 4) achieve greater synthesis with modeling approaches. New, Dec 2011! Lacey Knowles, Eli Sarnat, and I have been awarded a grant by the National Science Foundation to develop a regional Indo-Pacific phylogeny for Pheidole and test macroevolutionary and biogeographic theory. The project will start in 2012 and run for 2 years. More soon! Economo, E. (PI), L. Knowles (co-PI). NSF DEB 1141989. $378,522. "Evolving hyperdiversity in phenotypic, ecological, and geographic networks: testing the taxon cycle and alternatives in Indo-Pacific Pheidole." |
Publications and resources:
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--Economo, E. P., Sarnat E. M. Revisiting the ants of Melanesia and the taxon cycle: historical and human-mediated invasion of a tropical archipelago. Accepted. The American Naturalist. --Sarnat, E. M., Economo, E. P. The Ants of Fiji. Accepted. University of California Publications in Entomology. (88,000 word monograph) --Economo, E.P., Janda, M., Sarnat ,E. M. The island biogeography of native and invasive ant iversity reveals biotic resistance at large but not small scales. In Review. --Economo, E.P., Blanchard, B.*, Fasi, J., Sarnat, E.M. Checklist of the ants of the Solomon Islands and a new survey of Makira Island. In preparation. * undergraduate co-author --FijiAnts.org Our website about Fijian Ants and our projects there. (currently being updated, bear with us) --Fiji Page on Antweb. Antweb is fast becoming the dominant repository for biodiversity info on ants. -- Eli Sarnat's fantastic Pacific Invasive Ants Key (PIA). -- Checklist of the myrmecological holdings of the University of Michigan Museum of Zoology (a lot more than we thought, and hardly touched since the 50's). --Myrmecos blog post about our collecting trip to the Solomon Islands. |
