Amoebozoans - "Slime Molds"
Badhamia melanospora, a myxogastrid.
The key objectives of my research are to develop a better understanding with respect to the global patterns of distribution as well as the ecology of two groups of Amoebozoans (Amoebozoa): the myxogastrids (Myxogastria) and the dictyostelids (Dictyostelia). These organisms are common and often abundant in association with decaying plant materials and soil where they prey on bacteria and other microorganisms such as fungi and algae. Through these activities they exert a significant yet understudied and underappreciated role in ecosystem health and function.
Myxogastrids
Myxogastrids are also known as "myxomycetes" or "plasmodial slime molds" and they have been found in association with decaying vegetation from every terrestrial biome examined to date. They exhibit a remarkable life cycle that consists of microscopic (amoeba) as well as macroscopic (plasmodium) feeding stages and the latter can ultimately produce fruiting structures that superficially resemble those produced by fungi. A substantial portion of our knowledge with respect to this group has been derived from studies conducted in temperate forests of the northern hemisphere; as such, more current work has been concentrated in other regions. Despite this recent surge of investigations, researchers have only scraped the surface and much more remains to be discovered. To learn more about projects involving the Laboratory for Amoebozoan Studies, explore the surrounding links.
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Dictyostelids
Dictyostelids (also called cellular slime molds) are a rather fascinating group of Amoebozoans that are common and often abundant in the soil-liter interface zone of the forest floor where they feed primarily on bacteria. The fruiting structures produced by members of this group contain spores immersed in a gelatinous matrix and as a result these spores are likely disseminated by water and other organisms that serve as vectors. Once a spore finds suitable conditions, an amoeba emerges, begins feeding, and divides ultimately producing a large population. When food becomes scarce, a chemical signal is emitted which causes all of the cells in the vicinity to aggregate and produce a structure often referred to as a slug (which resembles a multicellular organism) that may or may not migrate and then produce fruiting bodies. Even though these organisms have received a fair amount of study, surveys carried out in novel microhabitats often produce previously undiscovered species. In a similar fashion, much remains to be discovered with respect to their distribution and ecology.
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Forest Dynamics
One area of my research focuses on forest community dynamics with a particular emphasis placed across the central Appalachian Mountains. These forests have been subject to a complex interplay of climate change, natural disturbances, and considerable anthropogenic influences. As a result, old-growth "virgin" forests are rather rare and limited in their areal extent. Events such as extensive logging operations (late 1800's and early 1900's), the chestnut blight, and acid rain deposition have altered the composition and structure of these forests. In addition, changing global climate as well as continued anthropogenic assaults continue to alter the ecological associations within these forests in ways that we do not yet understand. It is important to study these forests and characterize their responses because they are valuable for many purposes; such as, aesthetics, biodiversity, carbon sequestration, and wood products.
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Field Work
INTERNATIONAL
COUNTRY YEAR(S) Barbados 2012 Belize 2009 - 2012 Brazil 2011 Costa Rica 1998, 1999, 2011, 2013 Kenya 2011 Mexico 1999 Peru 2012 Puerto Rico 1998, 2002 Russia 2007 Thailand 2008, 2011, 2012 |
UNITED STATES
STATE/REGION YEAR(S) Arkansas 2005-2008 Cumberland Gap National Historical Park 2008-2012 Great Smoky Mountains 1999, 2000, 2002, 2006, 2009-2012 Grasslands (CO, KS, ND, NM, OK, SD, WY) 2006-2008 New Mexico (Saguaro National Park, Desert) 2007 Ohio/Pennsylvania (Old-growth forests) 2003-2005 Oklahoma (Cross timbers forest) 2005 West Virginia/Virginia 1997-2007, 2009, 2011, 2012 |
The Laboratory of Amoebozoan Research is housed in the Cumberland Mountain Research Center located on the campus of Lincoln Memorial University.
This website is created by Adam W. Rollins. Any content, statements and/or opinions included in these pages do not necessarily represent the views of Lincoln Memorial University.
© Adam W. Rollins, Ph.D.
2017
© Adam W. Rollins, Ph.D.
2017