OOS 6-9 - Reconstructing tropical biodiversity with DNA data and its implications for conservation

Monday, August 8, 2011: 4:20 PM
16A, Austin Convention Center
Daniel Janzen1, Winnie Hallwachs1, John M. Burns2, Isidro Chacon3, Tanya Dapkey1, Andy R. Deans4, Marc E. Epstein5, Bernardo Espinoza3, Mehrdad Hajibabaei6, Jason P. W. Hall2, Paul D. N. Hebert7, Donald J. Harvey2, Ian J. Kitching8, Donald J. Lafontaine9, Jacqueline Y. Miller10, James S. Miller11, Jean-Francoise Landry9, Scott E. Miller12, Jose Montero3, Sujeevan Ratnasingham7, Robert K. Robbins2, Josephine J. Rodriguez13, Rodolphe Rougerie7, Michael J. Sharkey14, Alex M. Smith7, Alma M. Solis15, Bolling J. Sullivan16, Paul D. N. Thiaucourt17, David B. Wahl18, Susan J. Weller19, James B. Whitfield20, Keith Willmott10, Monty D. Wood9, Norman E. Woodley15 and John J. Wilson7, (1)Department of Biology, University of Pennsylvania, Philadelphia, PA, (2)Department of Entomology, National Museum of Natural History, Washington, DC, (3)Inventario, INBio, Santo Domingo de Heredia, Costa Rica, (4)Department of Entomology, North Carolina State University, Raleigh, NC, (5)Plant Pest Diagnostic Branch, California Dept. of Food & Agriculture, Sacramento, CA, (6)Biodiversity Institute of Ontario, University of Guelph, Guelph, ON, Canada, (7)Canadian Centre for DNA Barcoding, Biodiversity Institute of Ontario, Guelph, ON, (8)Department of Entomology, The Natural History Museum, London, United Kingdom, (9)Canadian National Collection of Insects, Agriculture and Agri-Food Canada, Ottawa, ON, (10)McGuire Center for Lepidoptera and Biodiversity, Florida Museum of Natural History, Gainesville, FL, (11)Department of Entomology, American Museum of Natural History, New York, NY, (12)National Museum of Natural History, Washington, DC, (13)National Center for Ecological Analysis and Synthesis, Santa Barbara, CA, (14)Department of Entomology, University of Kentucky, Lexington, KY, (15)Entomology, SEL, USDA, Smithsonian Institution, Washington, DC, (16)Private home, Beaufort, NC, (17)Private home, Paris, France, (18)American Entomological Institute, Gainesville, FL, (19)Bell Museum of Natural History, University of Minnesota, Minneapolis, MN, (20)Department of Entomology, University of Illinois, Urbana, IL
Background/Question/Methods: A biodiversity inventory of the 120,000 terrestrial ha Area de Conservacion Guanacaste (ACG) in northwestern Costa Rica has been running for 33 years and has documented at least 9,000 species of Lepidoptera (and their parasitoids and food plants) of the estimated 15,000 species. In 2003 the inventory began routinely DNA barcoding all voucher specimens for identification and cryptic species discovery. How has this additional identification and species discovery technique changed the inventory results, and what are the implications of this change for community structure, specialization, and trophic web characterizations of diverse species arrays?

Results/Conclusions: DNA barcoding of every vouchered specimen in the inventory has

1) allowed a far faster and more certain field identification of inventory specimens, irrespective of whether to an interim name or a “final” scientific name;

2) found that 10 to 50 percent of morphologically-named OTUs in ACG are in fact pooled specimens (and hence biologies) of two or more species if not segregated according to their barcodes or other traits;

3) found that this species-level confusion becomes more frequent the smaller or more inconspicuous, or less studied, the specimens of the species being inventoried, with the exception that sometimes the most prominent and well-known species also turn out to be complexes, in part because “everyone knows the name of that one”;

4) found that within some higher taxa of parasitoids of caterpillars, the concept of “generalist” is rendered close to non-existent due to finding that many, though not all, “generalists” under one morphology-based name are a sympatric complex of highly host-specific species;

5) found that, as a byproduct of 4) above,  three-layered trophic webs (plant-caterpillar-parasitoid) are much more specialist structured than “expected”; and

6) decided that

a) there are significantly more species in ACG than anticipated by an estimate based on centuries of taxonomists’ morphology-based intuition,

b) climate changes will impact these specialist-based arrays more severely than imagined, and

c) tropical ecology is perhaps somewhat shakily based largely on the biology of those species that have been separate long enough, or directedly selected long enough in directions readily visible to 2 m tall diurnal large mammals, to be morphologically distinguishable, while DNA barcoding all “species” allows summary studies to also include (yet species-level distinguish) those species that are selected to be or remain similar, or not separate long enough to be morphologically distinguishable.

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