The plasmodial slime molds are fungus-like organisms usually present and often abundant in terrestrial ecosystems. Most of what is known about the assemblages of slime molds associated with particular types of terrestrial ecosystems has been derived from studies in temperate forests; relatively little information is available on assemblages associated with tropical forests. This research project seeks to characterize the assemblages of species associated with microhabitats and vegetation types not yet investigated in the Neotropics. Particular emphasis will be directed towards the assemblages of species associated with various microhabitats in the canopy of tropical moist forests and microhabitats potentially available to slime molds in tropical dry forests and other types of vegetation characteristic of more arid areas of the Neotropics.
The research will be carried out in three primary study areas: the Luquillo Experimental Forest in Puerto Rico, the Guanacaste Conservation Area in Costa Rica, and a portion of the state of Tlaxcala in eastern central Mexico. Specimens associated with specific microhabitats within each of these study areas will be collected in the field and obtained from moist chamber cultures prepared with samples of organic material from microhabitats being investigated. Most of the microhabitats to be investigated are accessible from the ground. However, gaining access to the canopy of a tropical forest is exceedingly difficult. Consequently, studies associated with various canopy microhabitats will be carried out in areas being subjected to active logging (i.e., samples will be collected from individual trees as soon as possible after a tree has fallen to the ground).
The data accumulated as a result of the research project funded by an earlier NSF grant provided evidence for a number of ecological patterns not previously reported for slime molds. The most important of these are that (1) species richness and [especially] relative abundance increase with decreasing (and not increasing, as might have been anticipated)with moisture conditions and (2) in tropical forests, distinct assemblages of slime moldsare associated with microhabitats that have no counterparts in temperate forests. The assemblages of slime molds associated these "new" microhabitats are characterized by the presence of significant numbers of species either new to science or previously considered to be exceedingly rare. It is anticipated that the research to be carried out during this project, which will include all of the major Neotropical vegetation types not previously investigated, will yield the data necessary to develop a fairly complete understanding of slime mold distribution patterns, ecology, and diversity in this region of the world. The project will include several undergraduates as active participants, and collaborations developed with scientists in Mexico, Puerto Rico, Costa Rica, England, Spain, Russia, and Germany will be continued.
