Norman J. Fashing
Research Interests and Projects
Ecology and BehaviourMy main interests center around arthropod behavior and ecology, especially mites. In this regard I have concentrated on the mite fauna of plant held waters (phytotelmata), e.g., the modified leaves of pitcher plants, inflated leaf axils of such plants as bromeliads and palms, water-collecting flowers such as Heliconia, internodal spaces of broken bamboo stems, and the water-collecting depressions of trees (treeholes). Research on phytotelm communities has taken me to the Pacific North West, U.S.A., to study the pitchers of the Cobra Lily (Darlingtonia californica), to the Cape York Peninsula, Far North Queensland, Australia, as well as to Thailand and northern Borneo, to study the mite inthabitants of the fluid-filled pitchers of Nepenthes species, to subtropical rain forests of Lamington National Park, Queensland, Australia and the tropical rain forests of Kakamega Forest, Kenya, to study water-filled treeholes, and to St. Georges Sound,West Australia, to study the West Australian Pitcher Plant (Cephalotus follicularis). In the Williamsburg area, however, the only phytotelm available for study is the water-filled treehole - most of my studies have therefore concentrated on this habitat.
Water-filled treeholes are in reality tiny ponds in the woodland ecosystem. They provide a unique habitat for a number of different organisms, many of them obligate inhabitants. The arthropod fauna is made up of only a relatively small number of common species in a given locality, and these include the same insect and mite families throughout the temperate regions of the world. Autumn-shed leaves provide the main energy source for the treehole community. Since they are physically small and harbor relatively few species, water-filled treeholes are excellent for studying community ecology.
Three species of mites are obligate treehole inhabitants in eastern North America, and I have studied their ecology and behavior for a number of years. Their life-history patterns are probably best summarized by stating that they emulate those species referred to ecologically as "K-selected" or "equilibrium species". Their feeding behavior is also quite interesting: one species utilizes suspended particulate matter (filter feeder), one grazes on fungal hyphae on surface of decomposing leaves, and one feeds on the decomposing leaves (shredder).
Although the biology of the mite inhabitants is fairly well known, few studies have been done concerning the insect inhabitants in the southeastern U.S. Even the exact species composition is unknown, and feeding behavior and trophic relationships need to be investigated. Such investigations require the development of techniques for rearing the arthropods on various potential food sources available in the treehole (e.g., leaves, fungi, other arthropods, etc.) as well as an examination of their mouthparts with scanning electron microscopy to determine if there is a correlation between diet and morphology. The ultimate goal is to develop a food web for the water-filled treehole community in eastern Virginia.
SystematicsEstimates indicate that only around ten percent of the mite fauna has been described. It is therefore not surprising that most of the species associated with micro-communities (e.g., phytotelmata, animal nests, etc.) are new to science. A part of my research effort is therefore directed toward describing new mite species associated with the micro-communities under study. I am currently describing the new species and, in some cases, new genera that inhabit the fluid-filled pitchers of Nepenthes pitcher plants in Thailand and Brunei. Species descriptions make excellent projects for students, especially undergraduates, interested in learning some of the techniques involved in scientific illustration.
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Last updated January 11, 2006