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Aquatic invertebrate biology is the primary theme of research in my laboratory that is operated as part of the Center
for Great Lakes Studies. The areas of greatest activity are centered on a broad array of basic and applied research.
Megaleaps in Invertebrate Evolution
A primary interest in our lab is understanding the evolutionary phenomena which lead to abrupt patches of
invertebrate diversity. The central premise is that vast retooling of invertebrate structure and function precedes
punctuated evolution which results in great diversity. These precursoral events were coined "megaleaps" in our lab. A great example is the surge from protozoan to multicellular life. The primordial protozoan stock that made this
advancement is believed to be a bottom dweller (e.g., amoeba) that was able to exploit large food sizes. Thus, the
switch from microphagy to macrophagy is thought to be concomitant with evolution of the early multicellular forms.
Moreover, for such a megaleap to have occurred at all presumes cell-cell communication and recognition were in
place. Megaleaps such as mesoderm formation, fundamental metamerism, reproductive novelties, and others
appear to have shaped the manner in which life functions. Do these same megaleaps place constraints on animal
adaptations? Is it possible to predict future megaleaps and the impact they will have? Another research activity involving perhaps the ultimate megaleap deals with understanding how one of primitive
earth's energy sources (lightning) interacts with atmospheric gases and substrates (e.g., water, clay, sand) to form
primitive life or at least its precursors. To this end, we have simulated natural lightning using controlled cold corona
discharges. This contrasts with other studies which have relied on uncontrolled sparks which by comparison are
simply not representative of natural discharges. This research has thus far resulted in three noteworthy
accomplishments, first the generation of a very homogeneous cold corona; second, carbon polymers and atomized
organics are produced; and third, their production using the cold corona is extremely fast, requiring only a few
seconds.
Graduate Studies
Students research based from my laboratory included 1) using Nuclear Magnetic Resonance (NMR) to enhance the
understanding of evolutionary relationships of aquatic invertebrates. 31PNMR spectral profiles suggest that
phospholipids are conserved to at least the family taxonomic level, 2) understanding the importance of
wetland/freshwater estuary interfaces, 3) elucidating lake sediment disturbances in changing lake water quality and
production, 4) determining the role of zebra mussels in shunting energy/material flow from the pelagic to the benthic,
and 5) determining the importance of dams in creating refugia for freshwater mussels.
Invasion by Exotics
The main emphasis in this research area is to better understand the consequences of invading species upon the
native, indigenous invertebrate fauna. Historically, exotics have had profound effects on molding community
structure. So great is the impact of some invasions that they can be delegated as "catastrophes" in much the same
way as massive glaciation, global volcanism, and others. The ecological catastrophe of invading species has
probably done more to alter communities than factors normally credited for these changes, such as predation,
competition, succession. What role do exotics play in shaping invertebrate communities? Is it possible to predict
native community changes based on the disturbance factors of an exotic?
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