Graduate Student Symposium 2012
Saturday, March 3, 2012
Biology/Physics Building Room 130, 9:00am to ~ 4:00pm
The EEB Graduate Student Symposium is an all day event where graduate students present their research to other graduate students and faculty. Any EEB graduate student can present: BSMS, masters, PhD, old and new students. New graduate students usually present research ideas or preliminary data, while those more ‘seasoned’ students present their most recent results, often in preparation for upcoming spring and summer meetings.
|8:30-9:00||Coffee & Tea|
|9:00-9:15||Dr. Kent Holsinger||Welcome address|
|9:15-9:30||Laura Cisneros||Effects of landscape structure on multiple dimensions of bat biodiversity|
|9:30-9:45||Vanessa Boukili||Refining ecological restoration techniques in the tropics|
|9:45-10:00||Lily Lewis||Evidence for Trans-Tropical Dispersal in the Dung Moss Genus Tetraplodon|
|10:00-10:15||Kellie Kuhn||Ontogenic variation in the benefits of ants to their host plants in an obligate mutualism|
|10:15-10:30||Jon Velotta||Sequencing and de novo assembly of the alewife gill transcriptome|
|10:30-11:00||Morning Break - Drinks and Fruit|
|11:00-11:15||Jessie Rack||Behavioral responses of Ambystoma maculatum larvae to predator chemical cues on a geographic scale|
|11:15-11:30||Jayme Csonka||Late Devonian Conichnus from Tioga, Pennsylvania: Evidence of Asexual Sea Anemone Reproduction|
|11:30-11:45||Brigette Zacharczenko||Caterpillar mysteries: mimicry and extreme phenotypic changes|
|11:45-12:00||Jeffrey Divino||Hold the salt! How sticklebacks deal with changes in salinity|
|12:00-1:30||Lunch - Sandwiches and Salad|
|1:30-2:00||Dr. Massimo Pigliucci, Professor, Department of Philosophy, CUNY-Lehman and CUNY-Graduate Center||Keynote Address: On the many meanings of "doing theory" in biology|
|2:00-2:15||Hamid Razifard||Elatine (riverworts): the coolest of plants!|
|2:15-2:30||Manette Sandor||Remnant Trees|
|2:30-2:45||Veronica Bueno||tapeworms of neotropical freshwater stingrays|
|2:45-3:00||Johanna Elsensohn||Spotted Wing Drosophila|
|3:00-3:15||Heidi Golden||Climate Change and Arctic Grayling Metapopulation Dynamics|
|3:15-3:30||Alejandro Rico-Guevara||Imagine if you could see in high-speed...|
|3:30-3:45||Robert Roehm||Land Use Patterns and Biodiversity in NE Ephemeral Pools|
|3:50-3:55||Russ Meister||Cicada Bacterial Endosymbionts|
|3:55-4:00||Photo Contest Results|
Dr. Massimo Pigliucci
Keynote Address: On the many meanings of "doing theory" in biology
“Theoretical biology” is a surprisingly heterogeneous field, partly because it encompasses “doing theory” across disciplines as diverse as molecular biology, systematics, ecology and evolutionary biology. Moreover, it is done in a stunning variety of different ways, using anything from formal analytical models to computer simulations, from graphic representations to verbal arguments. In this talk I explore a number of aspects of what it means to do theoretical biology, and how they compare with the allegedly much more restricted sense of theory in the physical sciences. I also tackle a recent trend toward the presentation of all-encompassing theories in the biological sciences, from general theories of ecology to a recent attempt to provide a conceptual framework for the entire set of biological disciplines. Finally, I discuss the roles played by philosophers of science in criticizing and shaping biological theorizing.
Late Devonian Conichnus from Tioga, Pennsylvania: Evidence of Asexual Sea Anemone Reproduction
A long section of Famennian (Late Devonian) strata along US Route 15 in Tioga, Pennsylvania exposes the transition between the shallow marine Lock Haven Formation and the terrestrial Catskill Formation. Numerous specimens of the ichnofossil Conichnus have been found in the transitional zone between these facies. These conical, lined burrows are typically interpreted as dwelling or resting traces of sea anemones. Different aspects of the burrows’ structure are visible on the tops, soles, and sides of beds. Sedimentary structures in this interval include mudcracks and microbial fabrics, and adjacent beds contain Skolithos. The Conichnus-bearing interval contains a few beds with low-diversity body fossil assemblages (e.g., lingulids and Cyrtospirifer), in contrast with the base of the section, which possesses a diverse marine fauna (primarily brachiopods). The Conichnus of Tioga are smaller than many occurrences described previously (diameter equals 4.5-9.5 mm, height equals 3+ times the diameter, where visible). Other, less well-preserved cnidarian ichnofossils (e.g., Bergaueria) have been described elsewhere in the Upper Devonian Appalachian Basin. Thus, sea anemones were not uncommon along the shores of the Catskill Sea. The Tioga specimens show interesting features such as disturbed laminae (equilibrium structures) representing adjustment by the sea anemones to background sedimentation. The trace makers were also able to exhume and reposition themselves after significant depositional events (several cm of sediment, equivalent to the depth of the trace). In some specimens, the burrows are aligned in chains, possibly representing asexual reproduction by binary fission.
Refining ecological restoration techniques in the tropics
Enrichment planting is a commonly used restoration technique, which is applied to increase species diversity or environmental services during forest regeneration. Our study provides guidance in selecting species for restoration activities, and is among the first to directly link species performance across different environmental conditions to easily measured plant functional traits. We used an experimental approach to test whether species’ ecological characteristics influence the ability of seedlings to survive in three successional stages. In October 2010 we transplanted seedlings of six species (three secondary-growth specialists and three old-growth specialists) into old-growth forest, second-growth forest, and pasture plots at La Selva Biological Station in Costa Rica. Secondary-growth specialists possess fast-resource acquisition traits- such as high specific leaf area and low leaf toughness- that promote fast growth rates. Old-growth specialists, on the other hand, possess resource-conservation traits that promote survival over growth. We monitored seedling survival monthly for 1.3 years. Growth rates of survivors were assessed after 6 and 16 months (final harvest will be completed in March 2012). We use logistic and linear statistical models to relate species survival and growth rates to leaf functional traits and environmental conditions in each plot.
Hold the salt! How sticklebacks deal with changes in salinity
The ability to maintain internal ion homeostasis in freshwater or saltwater has enabled euryhaline fishes to colonize a wide range of aquatic habitats. However, the energetic cost of this osmoregulation is high because it involves active transport mechanisms that pump ions against electrochemical gradients, often occurring at the gill epithelia-water interface. For euryhaline populations presently occupying stable environmental salinities, will relaxed selection on hypo- or hyperosmoregulation result in a loss of that capacity, or alternatively, can these fish still acclimate to a wide range of salinities? My research seeks to answer this question in a Pacific northwest lineage of threespine stickleback (Gasterosteus aculeatus) consisting of distinct anadromous and lake ecotypes, which descended from an extant marine ancestor following the glacial retreat ca. 10,000 years ago. I raised embryos from each group at a common salinity and later transferred juveniles into either freshwater (<0.5 ppt) or saltwater (35 ppt) for two weeks. I then examined gill tissue from survivors to compare activity of an important ion transport protein involved in osmoregulation, sodium-potassium ATPase (NKA). Survival of lake and marine juveniles was highest in the salinity treatments that approximated native conditions. NKA activity differed among populations and was 19% higher the saltwater treatment overall. Within populations, fish tended to increase NKA activity in response to seawater, in some cases by 26-38%. These stickleback populations have physiologically diverged in their toleration of and cellular osmoregulatory response to foreign salinities. Local salinity adaptation may be an important ecological characteristic that isolates aquatic organisms.
Systematics of Elatine L. (Elatinaceae) using morphological, micromorphological, and molecular traits
My research focus is on systematics and evolution of the genus Elatine. Twelve Elatine species are naturally found in Eurasia (3 of which have been also reported from northern Africa), 10 species in North America, 5—7 species in temperate to mountainous zones of South America, two species in Malaysia and India, two species in southern Africa, and one species in Australasia. In the US, two species from this genus are reported to be invasive in recent decades: Elatine triandra (threestamen waterwort), and E. ambigua (Asian waterwort). Ploidy levels and chromosome numbers still remain unknown for many species in the genus; consequently, the hybridization process in this group remains obscure. As understanding the hybridization process in many plant groups is necessary for understanding the evolution of invasive species, chromosome studies seems to have great priority in this group. My goal is to publish a monograph of American Elatine species, using morphological traits, chromosome counting, and molecular phylogeny. Such a monograph will include an identification key, species descriptions, accurate pictures, and distribution maps, based on recent collections from the entire US.