| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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| here at the academy Under the MicroscopeJohn Patrick Kociolek John Patrick Kociolek has bagged his research quarry in granite-rimmed Sierra Nevada basins, along wave-swept shorelines of the Great Lakes, and in backwater sloughs of the Okefenokee Swamp. His samples push the Academy's holdings to over 55,000 specimens from some 15,000 locations, the third largest collection in the world. Yet the entire collection occupies a few cabinets along a single wall. Kociolek studies diatoms, unicellular aquatic plants that build ornate cell walls made of silica. Some diatoms resemble miniature snowflakes. Others look like chips of etched crystal. "These things live inside glass houses," Kociolek says. They are "aesthetically pleasing organisms to look at." These tiny jewels pack an ecological wallop. Together with other forms of algae, diatoms form the base of aquatic food chains, converting sunlight into edible energy. Organisms from nudibranchs to whales to humans all depend on their photosynthesis. Diatoms remain useful after they die. Over millennia, their tough silica shells accumulate into deposits of diatomite, a rock used in the manufacture of abrasives, chemical filters, and insulating materials. Fossil diatoms also provide a record of past ecological conditions for scientists to read. As G Dallas Hanna Chair and curator of diatoms at the Academy since 1989, Kociolek has spent a lot of time deciphering diatom stories. He specializes in diatom taxonomy and phylogeny. He defines species by noting systematic differences in the details of the cell walls. He scans the miniature silica landscapes, searching the ridges, pores, and horns for clues that could shed light on diatom evolution. Since 1993 Kociolek has also served as the Academy's Director of Research, turning his attention to the minutiae of research administration. One of his priorities is to foster multidisciplinary research at the Academy. Initiatives under discussion include a Center for Biodiversity Research and Information and an institutional database that would merge data from the Academy's various departments. Another project, designed to inspire a new generation of taxonomists, is a Summer Systematics Institute. Starting this summer, ten undergraduates will work on research projects with Academy scientists and attend lectures on systematics. If some of these students become diatom taxonomists, they'll have plenty to work on. Kociolek discovers new species on almost every collecting trip, even in seemingly well-studied places like Mono Lake. When he and a colleague surveyed Mono Lake's diatoms, "Something like five out of the eight most dominant taxa were new to science." He has also discovered new diatom species in a group of Sierra Nevada lakes north of Sierra City. He says diatom remains in the sediments of such lakes could be used to study the effects of gold rush-era deforestation on aquatic ecosystems. "Diatoms are very good indicators of water quality," Kociolek says. "You can look at quantitative and qualitative differences in the diatom communities over time, and relate them to environmental variables. The story is in the sediments. It just needs to be looked at." Scientists also use diatoms to reconstruct Earth's climate history. In December 1994, Kociolek hosted a National Oceanic and Atmospheric Administration-funded workshop at the Academy to plan a diatom "data cooperative" for paleoclimatologists. He says the cooperative would provide a consistent, reliable diatom taxonomy for building models of ancient climates. Kociolek's interest in aquatic biology surfaced early on; he recalls writing a paper on algae in the second grade. After starting college as a history major, a summer course on algae rekindled his interest in science. He did so well in the class that the instructor invited him to do a master's thesis at Bowling Green State University in Ohio. Another summer course, on diatom taxonomy, inspired Kociolek's Ph.D. studies at the University of Michigan and his subsequent research career. Kociolek relishes opportunities to share his love of aquatic science. He teaches summer courses on algae and diatoms at field stations in the Sierra Nevada and in Iowa, and enjoys showing diatoms to the public when the Academy holds open house. A favorite demonstration features Gomphoneis, a diatom that propels itself by squirting mucilage through a slit in its cell wall. "Here's an organism that's photosynthetic, but it's moving," Kociolek says. "Things are not easily broken down into plant and animal. The diversity of life is much greater than the simplistic way we usually think about things." Kociolek enjoys his work as Director of Research, but says he also likes to slip downstairs to the diatom collection. Gazing over bookshelves filled with rare old diatom texts, he muses, "The neat thing about taxonomy is that I can still get my history fix. I get to use this rich historical literature." But the stacks of venerable tomes contain big knowledge gaps. Kociolek estimates that far less than half of the world's diatom species have been described. He notes that diatomists have only had a few decades, since the development of the electron microscope in the 1920s, to build a detailed taxonomy. He tells his colleagues in mammalogy and ornithology, "There have been taxonomies for mammals and birds ever since there were people, so you've had one and a half million years to figure them out. Give us a million and a half years and we'll figure out the diatoms!"
David K. Hill is a freelance science writer in San Francisco. |
Spring 1995
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