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Smithsonian National Museum of Natural History
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Epinotia sotipena, Brown, 1986

Epinotia sotipena Brown, 1986. Holotype specimen. Citation: Brown. 1986. Journal of the Lepidopterists' Society. 40: 341. Collection: R. Hodges, Maryland, Montgomery Co., Plummers Island, Potomac River, 7 Apr 1962

Research Training Program 2006

Summary

Intern Name Advisor Name(s) Department Project Title
Jorge Alvarez William DiMichele and Conrad Labandeira Paleobiology Reconstructing a Permian Tropical Forest: Vegetational Compositions and Patterns of Herbivory
Emily Armgardt Ellen Strong Invertebrate Zoology Ontogenetic Changes in Shell Microstructure of Freshwater Gastropods from Lake Tanganyika (Cerithioidea, Paludomidae) 
Madison Barkley Mike Wise Mineral Sciences F-OH- Substitution and Thermal Effects on the Crystal Structure of Pegmatitic Topaz
Julia Brown Gene Hunt Paleobiology Body size evolution in deep-sea ostracodes 
Bryan Cockrell Ed Vicenzi Mineral Sciences The Origins of Layered Carbonates in Peridotite Xenoliths
Megan Ennis Tim McCoy Mineral Sciences Hydrovolcanics on Mars: Comparison of Home Plate and Zuni Salt Lake, New Mexico
Katherine Faust Terry Chesser and Morton Isler Vertebrate Zoology, Birds Morphological and genetic variation in Amazonian antwrens 
Paige Hamilton Dave Hunt Anthropology The White Plague: Skeletal Evidence of Tuberculosis
Jayme Job Eric Hollinger Anthropology Pipestone Provenance: Sourcing Prehistoric Pipestone Artifacts within Museum Collections Using Reflectance Spectroscopy
Sheena Ketchum Paulina Ledergerber Anthropology Analysis of Ceramic Collections from Morona-Santiago, Southeast Ecuador
Sara Marsteller Don Ortner Anthropology Evidence of scurvy in North American archaeological skeletal remains
Juan Andres Martinez Don Wilson Vertebrate Zoology, Mammals Geographic Variation in "Grey Four Eyed Pouched Opossums" Genus Philander (Didelphiomorphia, Didelphidae) 
Caleb McMahan George Zug Vertebrate Zoology, Amphibians and Reptiles Geographic Variation in the Morphology of Hemidactylus bowringii (Reptilia: Squamata: Gekkonidae) in Myanmar and Yunnan, China
Sylvia Moses Ed Vicenzi Mineral Sciences Characterizing Chemical Biosignatures of the Gunflint Chert
Alisa O'Connor Eric Hollinger Anthropology Carving Culture: Stylistic Analysis of Catlinite Forms Through Time 
Matthew Oreska Matt Carrano Paleobiology An Analysis of the Cloverly Formation (Lower Cretaceous) Microvertebrate Fauna from the Bighorn Basin, Wyoming 
Nick Rasmussen Richard Thorington Vertebrate Zoology, Mammals A Study of Flying Squirrels of Southeast Asia (Sciuridae: Hylopetes)
Erin Saupe Brian Huber Paleobiology Is Heterohelix rajagopalani the Ancestor of Gublerina cuvillieri? A Phylogenic and Taxonomic Study
Maya Strahl Vicki Funk Botany Evolution of the Lost World Mutisieae
Kimberly Vann John Brown Entomology Inventory of the Butterflies (Hexapoda: Lepidoptera: Papilionidae, Pieridae, Lycaenidae, Nymphalidae, Hesperiidae) of Plummers Island, Maryland

Research Abstracts

Reconstructing a Permian Tropical Forest: Vegetational Compositions and Patterns of Herbivory

http://www.nmnh.si.edu/rtp/students/2006/images/alvarez_advisor1.jpg Jorge Alvarez
University of Puerto Rico, Mayaguez
Mayaguez, Puerto Rico

William DiMichele, Ph.D.
Supervising Scientist
Department of Paleobiology

Conrad Labandeira, Ph.D.
Supervising Scientist
Department of Paleobiology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/alvarez_poster.jpg
In recent years the interest for the study of plant-insect interactions has risen in the scientific community. However, very little has been published on this about Early Permian floras. The late Paleozoic was a time of very drastic changes for Earth's climate, shifting from an Icehouse to a Greenhouse climate. This is the most recent model for such an event that is available for study. To have a better idea of what the ecosystem was like during such an event, we chose samples from four locations of the Colwell Creek Pond site of north-central Texas, which corresponds to this time period, and made qualitative and quantitative analysis of the flora. The site is composed by series of rock layers, called redbeds that occur throughout north-central Texas. During the Permian, this was the western tropical margin of the Supercontinent Pangea and the specimens found here are classic examples of an Early Permian biota. By analyzing and quantifying the insect interactions with this flora and comparing it to various other projects currently taking place in the United States, Brazil, and South Africa, it might be possible to establish a pattern for the herbivory of these insects. There were three dominant species in the flora of these four sites: Auritifolia waggoneri (common - 34.14%), Walchian conifer type 1 (common - 34. 14%), Taeniopteris type 1(common - 25. 33 %). The majority of the specimens were rare, with only 1 or 2 counts in some cases. Out of all the specimens Auritifolia waggoneri showed the most damage, with 58.71% of the samples being affected. The other two affected were Taeniopteris type 1 (minimum damage) and conifers type 1 and 3 (with what appear to be galls). Very few other taxa were affected, but their count was so low that a significant count could not be achieved.

This research was supported by a grant from the Latino Initiatives Fund.




Ontogenetic Changes in Shell Microstructure of Freshwater Gastropods from Lake Tanganyika (Cerithioidea, Paludomidae)

http://www.nmnh.si.edu/rtp/students/2006/images/armgardt_advisor2.jpgEmily Armgardt
Seattle University
Seattle, Washington

Ellen Strong, Ph.D.
Supervising Scientist
Department of Invertebrate Zoology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/armgardt_poster.jpg
Ancient lakes and their unique faunas present unparalleled opportunities for studying the patterns and processes of evolution and speciation. Lake Tanganyika, an ancient lake located in the Western Rift Valley of southeast Africa is known for hosting many endemic species including fishes, crabs, and gastropods. Unlike many other freshwater gastropods, the gastropods of Lake Tanganyika have highly decorated and thickened shells. West & Cohen (1996) have identified predator/prey co-evolution between gastropods and shell crushing crabs as the source for the unusual shells found in the lake. They quantified the number of cross-lamellar layers, up to four, in a sub-sample of species, and postulated that the additional shell layers impede predation by shell crushing. However, this study did not closely examine the ontogenetic sequence of the shell microstructure present in the shell. Eighteen different species were embedded in resin and examined with scanning electron microscopy to reveal the ontogenetic sequence of microstructure. The emergent pattern in the shell microstructure of many different species was a very simple larval shell, with additional variant cross-lamellar layers added during the juvenile stage, and then simplification of the layers when adult. This finding runs contrary to a predator/prey hypothesis because the additional layers claim to inhibit predation are not present in the adult.

This research was supported by grants and donations to the Research Training Program.




F-OH- Substitution and Thermal Effects on the Crystal Structure of Pegmatitic Topaz

http://www.nmnh.si.edu/rtp/students/2006/images/barkley_advisor1.jpg Madison Barkley
Mount Holyoke College
South Hadley, Massachusetts

Mike Wise, Ph.D.
Supervising Scientist
Department of Mineral Sciences

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/barkley_poster.jpg
Pegmatites are intrusive igneous rocks that are characterized by unusually large grain sizes (> 20mm). There are two geochemical types of granitic pegmatites, LCT and NYF. LCT pegmatites are rich in lithium (Li), cesium (Cs), and tantalum (Ta) and are usually associated with orogenic granites. NYF pegmatites are related to anorogenic granites and are enriched in niobium (Nb), yttrium (Y), and fluorine (F). Topaz is a fluorine-rich mineral that commonly occurs in pegmatites; however, topaz is more common in NYF pegmatites than in LCT pegmatites. The focus of this project was to examine the changes in topaz crystal structure caused by F-OH- substitution and to investigate the structural changes due to temperature in order to determine if there are structural differences between topaz from LCT pegmatites and topaz from NYF pegmatites. In this study, 32 topaz samples from 26 localities were analyzed for unit-cell parameters, fluorine content, trace element content, and heating effects. Cell parameters were calculated from X-ray diffraction data, and fluorine content was obtained by electron microprobe analysis. As consistent with other topaz studies (Alberico et al. 2003), the b unit-cell dimension decreases with increasing F content. Also consistent was a less defined decreasing trend in the a unit-cell dimension as F content increases. No correlation was found between the c cell dimension and any other cell-dimension or compositional variation. Plots of the pegmatitic topaz from this study show distinct and separate linear trends between NYF and LCT pegmatites when comparing the b unit-cell dimension to the F content. Trace element analysis by X-ray fluorescence shows the presence of Ge, Cr, Pb, Ga, W, and Rb but yields no correlation between trace elements and unit-cell variations. Selected samples were chosen for a heat study. Samples were heated at 700oC for 1 hour. After heating, the unit-cell volume of the topaz generally decreased but no trends separating NYF pegmatites from LCT pegmatites were found.

This research was supported by grants and donations to the Research Training Program.




Body size evolution in deep-sea ostracodes

http://www.nmnh.si.edu/rtp/students/2006/images/brown_advisor2.jpgJulia Brown
Vanderbilt University
Nashville Tennessee

Gene Hunt, Ph.D.
Supervising Scientist
Department of Paleobiology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/brown_poster.jpg
This study examined evolutionary trends in the body size of deep-sea ostracodes, and aimed to elucidate the mechanisms underlying Cope’s Rule: the tendency for body size to increase over time. Previous work has indicated that increases in body size of the ostracode genus Poseidonamicus were significantly correlated with decreases in deep-sea temperatures during the Cenozoic. Sixteen ostracode lineages from two sites on the Indian Ocean floor were examined to see if the same pattern appeared across additional sites and species. Ostracode body size (approximated by log-area) was measured using the software Image J and charted over a period of approximately 40 million years. The number of body size increases and decreases were counted between adjacent samples, and entire sequences were tested for directional trends using random walk models. Although ostracode body size showed intervals of both increase and decrease over time, there is evidence of an overall trend toward larger size, as body size increased over time in thirteen of sixteen lineages. Including both sites and all lineages, there were 38 body size increases between adjacent time periods, and 28 decreases, and the number of significant increases (13) nearly doubled the number of significant decreases (7). Concordant increases in body size emerge during the late Oligocene at DSDP site 253 and during the Pliocene at DSDP site 254. However, the exact patterns of body size evolution appear to differ between species and sites. This indicates that although a cooling global climate may be driving the general trend toward increasing body size in deep-sea ostracodes, there are many other local and species-specific factors capable of influencing body size evolution.

This research was supported by grants and donations to the Research Training Program.





The Origins of Layered Carbonates in Peridotite Xenoliths

http://www.nmnh.si.edu/rtp/students/2006/images/cockrell_advisor2.jpg Bryan Cockrell
Princeton University
Princeton, New Jersey

Ed Vicenzi, Ph.D.
Supervising Scientist
Department of Mineral Sciences

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/cockrell_poster.jpg
Layered carbonates are found in lava-coated peridotite mantle xenoliths from the Sverrefjell basaltic volcano, which erupted through a glacier one million years ago during the Pleistocene and is located in the Bockfjord volcanic complex in Svalbard, Norway. Some carbonate globules are nearly identical to ones detected in Martian meteorite ALH84001 in size, shape, and chemical zoning and thus, the Sverrefjell depositions serve as a terrestrial analog of Martian aqueous alteration in ultramafic rocks. This investigation, based predominantly on two peridotite xenoliths, sought to characterize the variety of the carbonates' (and associated low-temperature silicates') textures and mineral chemistry in order to constrain their source fluid(s) and relative timing. The depositions, referred to as globules, were found as infilling at mineral grain boundaries and grain junctions. X-ray spectra, extracted from an energy dispersive detector mounted on a variable pressure scanning electron microscope (VPSEM), aided in the initial mineralogical characterization of the phases in globules from the two samples. Wavelength dispersive x-ray spectroscopy performed with an electron probe microanalyzer (EPMA) confirmed the fine-scale (submicrometer) intergrowth of silicates with carbonates in one sample and the presence of pure carbonates in the other. Several carbonates rich in Ca, Mg, and Fe were commonly observed while the most frequently observed silicate was a Fe-rich clay (saponite). Textures are consistent with carbonate deposition by hydrothermal waters as previously proposed. Multiple populations of carbonates and later silicate veins clearly indicate complex secondary mineralization by low-temperature fluids. Magmatically driven hydrothermal waters are likely responsible for dissolution of many of the veinlets as well as precipitation of the carbonates while ambient glacial groundwater may be the source for deposition of late saponitic clays.

This research was supported by grants and donations to the Research Training Program.




Hydrovolcanics on Mars: Comparison of Home Plate and Zuni Salt Lake, New Mexico

http://www.nmnh.si.edu/rtp/students/2006/images/ennis_advisor1.jpg Megan Ennis
Morehead State University
Morehead, Kentucky

Tim McCoy, Ph.D.
Supervising Scientist
Department of Mineral Sciences

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/ennis_poster.jpg
The Mars Exploration Rover mission objective is to find evidence of past water. While Opportunity’s landing site showed clear evidence in the water-lain sediments of the bedrock, Spirit has operated for more than two years before finding promising evidence for water. After traversing the Columbia Hills, Spirit approached the light-toned circular feature (~80m in diameter) known as “Home Plate”. In this work, we have tested whether Home Plate was formed by a hydrovolcanic eruption as a single event, or by eruption and subsequent aeolian reworking, by comparing the Mars deposits with various hydrovolcanic sites in New Mexico. To accomplish this goal, observations were made during one week of field work (June 11-June 16, 2006) completed in New Mexico at sites analogous to Home Plate. The goal of the field work was to document deposits of terrestrial hydrovolcanic maar volcanoes. Sites visited include Valles Caldera, White Rock Canyon, Montoso Maar, and most importantly Zuni Salt Lake. At Zuni Salt Lake a stratigraphic section, at a comparable scale to that of Home Plate (~2m), was measured and described. Samples were collected at these various sites for further analysis and later reference. Photographic images were taken along with descriptive field notes in order to document the features that were observed. These images were then compared to the images of Home Plate. We noted similarities, including low angle cross-bedding, accretionary lapilli, bomb sags, tephra beds, fine-grained finely layered units, alternating layers of coarse and fine clasts or tephra and vesicular basalt lag deposit cap. Differences, including collapse features, accidental (bedrock) material, and palagonite were also noted as being present at Zuni Salt Lake while absent at Home Plate. While each of the New Mexico sites demonstrates similar features to those seen at Home Plate, Zuni Salt Lake provides the most accurate terrestrial analog based on lateral extent and overall scale. Zuni Salt Lake is classified as a maar on the basis that slumping around the crater rim is evident and a large amount of accidental (bedrock) material is present. Lack of slumping and accidental material indicates that Home Plate is probably not a maar, but a tuff ring dominated by magma material. Low angle cross beds are found in both types of deposits; therefore, features found at Home Plate can result from a base surge produced by a hydrovolcanic eruption. The hydrovolcanic tuff ring model allows for all features observed at Home Plate, including the cross-bedding, to be accounted for within a single volcanic event, without requiring a later stage of wind-reworking. This style of eruption indicates that there once was water at or below the surface of Mars.

This research was supported by grants and donations to the Research Training Program.




Morphological and genetic variation in Amazonian antwrens

http://www.nmnh.si.edu/rtp/students/2006/images/faust_advisor2.jpg Katherine Faust
Louisiana State University
Baton Rouge, Louisiana

Terry Chesser, Ph.D.
Supervising Scientist
Department of Vertebrate Zoology, Birds

Morton Isler, Ph.D.
Research Associate
Department of Vertebrate Zoology, Birds

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/faust_poster.jpg
One important objective of systematic biology is to classify variation in the natural world into a meaningful evolutionary and taxonomic framework. In the field of ornithology, this has most often been done using qualitative analysis of plumage characters. These assessments, however, may not reflect natural evolutionary units (species or subspecies). Now, with new genetic and morphological techniques available, it is possible to quantitatively assess variation among and within species and determine whether current taxonomic designations do, in fact, reflect evolutionary history. This project evaluated genetic and morphological variation among subspecies of three Amazonian antwrens in the genus Myrmotherula: M. longipennis, (Long-winged Antwren) M. menetriesii, (Gray Antwren) and the species complex M. hauxwelli/guttata (Plain-throated/Rufous-bellied Antwrens). This is the first quantitative study of plumage variation and is among the first comprehensive studies of genetic variation in pan-Amazonian birds. All subspecies that were sequenced formed distinct genetic units, and female plumage variation was found to be distinctive within nearly all of these units. Only M. h. hauxwelli was difficult to distinguish on the basis of quantitative morphological characters. Furthermore, the subspecies M. hauxwelli clarior appears to contain two distinct genetic groups, and although no comparative genetic information was available, two distinct plumage groups were also identified within M. menetriesii berlepschi. These results emphasize the importance of independent quantitative examination of plumage in combination with genetic analyses. The concurrence between morphological and genetic data in these birds also mirrors findings from other emerging studies of tropical birds, whereas studies of temperate zone birds have often found plumage differences to be more pronounced than genetic differences.

This research was supported by grants and donations to the Research Training Program.




The White Plague: Skeletal Evidence of Tuberculosis

http://www.nmnh.si.edu/rtp/students/2006/images/hamilton_advisor1.jpgPaige Hamilton
University of Notre Dame
Notre Dame, Indiana

Dave Hunt, Ph.D.
Supervising Scientist
Department of Anthropology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/hamilton_poster.jpg
Literature searches on the prevalence of tuberculosis lesions in 20th Century skeletal remains have revealed a disparity in expression of lesions on the ribs. This study intended to investigate the incidence of skeletal evidence of tuberculosis to clarify inconsistencies in the reported literature. A sample of 150 individuals was randomly-selected from three causes of death subgroups: pulmonary tuberculosis, non-specific tuberculosis, and non-tuberculosis. Results from this study show that a significant number of individuals with pulmonary tuberculosis (66%) and with non-specific TB (62%) displayed rib lesions, while only 16% of those dying from non-tuberculosis demonstrated this lesion type. Spinal lesions were also evaluated in this study. The frequency of both rib and spine lesions in individuals dying from pulmonary TB and non-specific TB was 38% and 36%, respectively, while only 8% of non-tuberculosis displayed both lesions. Although other possible diseases may respond in a similar way, the presence of lesions on the visceral side of the ribs and in conjunction with lesions on the anterior body of the spine would be highly diagnostic for an individual suffering from tuberculosis.

This research was supported by grants and donations to the Research Training Program.




Pipestone Provenance: Sourcing Prehistoric Pipestone Artifacts within Museum Collections Using Reflectance Spectroscopy

http://www.nmnh.si.edu/rtp/students/2006/images/job_advisor1.jpgJayme Job
Minnesota State University, Moorhead
Moorhead, Minnesota

Eric Hollinger, Ph.D.
Supervising Scientist
Department of Anthropology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/job_poster.jpg
Sourcing archaeological artifacts has proven extremely useful in discerning prehistoric trading patterns and cultural contacts. This study widens the scale of many past sourcing projects by considering an entire museum’s pipestone collections rather than an individual object type or site. Advancements in the technology of geophysical sourcing, such as non-destructive reflectance spectroscopy, have made access to many previously restricted artifacts possible. By analyzing much of the pipestone collection housed by the Smithsonian’s National Museum of Natural History and National Museum of the American Indian using reflectance spectroscopy, existing notions of prehistoric trade on the plains may be detected and supported.

This research was supported by grants and donations to the Research Training Program.




Analysis of Ceramic Collections from Morona-Santiago, Southeast Ecuador

http://www.nmnh.si.edu/rtp/students/2006/images/ketchum_advisor1.jpgSheena Ketchum
University of Notre Dame
Notre Dame, Indiana

Paulina Ledergerber, Ph.D.
Supervising Scientist
Department of Anthropology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/ketchum_poster.jpg
This project is an analysis of the prehistoric ceramic collections excavated at two sites in Morona-Santiago, Southeast Ecuador. The analysis showed that the collections were made with very coarse grit and made with very diverse methods of decoration; there is also a high percentage of corrugated sherds present. These findings suggest that there was more than one culture using the sites and/or that the culture or cultures that constructed the vessels were not specialized at manufacturing pottery.

This research was supported by grants and donations to the Research Training Program.



Evidence of scurvy in North American archaeological skeletal remains

http://www.nmnh.si.edu/rtp/students/2006/images/marsteller_advisor2.jpgSara Marsteller
Cornell College
Mount Vernon, Iowa

Don Ortner, Ph.D.
Supervising Scientist
Department of Anthropology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/marsteller_poster.jpg
Subadult skulls from archaeological sites in Maryland and Georgia were examined for evidence of scurvy. Diagnoses of scurvy were made based on the presence of multiple lesions of abnormal porosity or porous bone formation in multiple areas of the skull known to be associated with hemorrhage in patients with the disease. Scurvy was prevalent in 15.4% of the skulls examined from the Maryland site. Only a few possible cases were found in the Georgia sample. We suggest that the lack of scurvy in the latter sample is most likely the result of an unrepresentative sample and not an indication of adequate vitamin C in the diet.

This research was supported by grants and donations to the Research Training Program.



Geographic Variation in "Grey Four Eyed Pouched Opossums" Genus Philander (Didelphiomorphia, Didelphidae)

http://www.nmnh.si.edu/rtp/students/2006/images/martinez_advisor1.jpgJuan Andres Martinez
University of the Republic of Uruguay
Montevideo, Uruguay

Don Wilson, Ph.D.
Supervising Scientist
Department of Vertebrate Zoology, Mammals

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/martinez_poster.jpg
On the basis of morphological criteria, five main groups of Philander were recognized, though some of them seemed to be composites of more than one species and subspecies. Within the "frenatus group" the greatest resolution was achieved. The subgroup endemic to the Chiquitano dry forest biome of east-central Bolivia, currently not recognized taxonomically, showed enough morphological distinctness to be considered a valid form of Philander, which we argue should be upgraded to species level, Philander crucialis (Thomas, 1923).

This research was supported by grants and donations to the Research Training Program.



Geographic Variation in the Morphology of Hemidactylus bowringii (Reptilia: Squamata: Gekkonidae) in Myanmar and Yunnan, China

http://www.nmnh.si.edu/rtp/students/2006/images/mcmahan_advisor1.jpgCaleb McMahan
Erskine College
Due West, South Carolina

George Zug, Ph.D.
Supervising Scientist
Department of Zoology, Amphibians and Reptiles

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/mcmahan_poster.jpg
The Southeast Asian country of Myanmar (formerly Burma) has five currently recognized species of geckos within the genus Hemidactylus. This genus is among the most speciose of the gekkonids with approximately 80 known species, some of which only recently described (Baha el Din, 2003, 2005; Henle & Böhme, 2003). Hemidactylus are united by derived traits in toe morphology of the manus and pes; however there is sizeable variation among species in traits such as head proportions, body and limb size, degree of division in toe lamellae, and scalation patterns. Due to these variations, as well as widespread geographic ranges, Hemidactylus is systematically difficult. A recent molecular study utilizing two mitochondrial genes from 30 species of Hemidactylus shows genetic divergence within the tropical Asian clade, consisting of two monophyletic groups (Carranza & Arnold, 2006). The purpose of this project was to conduct a systematic study of one of the Burmese species, H. bowringii, to determine if morphological differentiation has occurred alongside the genetic divergences. Mensural and meristic (scalation) characters were adapted from Zug et. al., 2003. Data were collected from samples from throughout Myanmar and Yunnan, China. Data were analyzed using Systat 11. Results show significant (P<0.05) differences between the two H. bowringii clades. However, morphological differentiation also occurs throughout other parts of Myanmar, with potentially more divergences within this species than represented in the phylogeny.

This research was supported by grants and donations to the Research Training Program.



Characterizing Chemical Biosignatures of the Gunflint Chert

http://www.nmnh.si.edu/rtp/students/2006/images/moses_advisor3.jpgSylvia Moses
University of California, Berkeley
Berkeley, California

Ed Vicenzi, Ph.D.
Supervising Scientist
Department of Mineral Sciences

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/moses_poster.jpg
Microfossils of the Gunflint chert (Schreiber Beach, Ontario, Canada) are 1.9 Ga in age and contain the first well-supported evidence suggesting the existence of life on Earth during the Precambrian. These microfossils, ranging from 1-20 micrometers in diameter, display filamentous or spheroidal morphologies, and are primarily composed of quartz. Microanalysis of the carbon-rich regions associated with these microfossils and organic residues in the chert could be key to establishing chemical biosignatures for these primitive life forms. A variety of techniques including low-vacuum scanning electron microscopy (VP SEM), Raman spectroscopic imaging, and cathodoluminescence were used to study the type and distribution of carbon in the microfossils and the chert matrix. The cathodoluminescence of the chert indicated homogenously distributed chemical impurities in the quartz. The low-vacuum SEM x-ray method was problematic for localizing carbon owing to severe carbon absorption by the silica matrix. Raman laser spectroscopy proved highly useful providing elevated sensitivity to carbon and the ability to distinguish graphitic (G) from disordered (D) carbon. This methodology revealed increased concentrations of carbon in microfossils and other kerogenous areas. The G/D ratio is an indication of the chert's thermal maturity, and the large variation of the bulk carbon G/D ratio within the same hand-sample implies local heating by small (centimeter-scale) hydrothermal veins. The G/D ratio of carbon within the microfossils and the organic residue in the quartz are nearly identical suggesting they are derivative of similar sources of carbon. Further microchemical evaluation should lead to an improved understanding of chemical biosignatures for preserved primitive life forms.

This research was supported by the Bill and Jean Lane Endowment.



Carving Culture: Stylistic Analysis of Catlinite Forms Through Time

http://www.nmnh.si.edu/rtp/students/2006/images/oconnor_advisor1.jpgAlisa O'Connor
University of Notre Dame
Notre Dame, Indiana

Eric Hollinger, Ph.D.
Supervising Scientist
Department of Anthropology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/oconnor_poster.jpg

This research was supported by grants and donations to the Research Training Program.




An Analysis of the Cloverly Formation (Lower Cretaceous) Microvertebrate Fauna from the Bighorn Basin, Wyoming

http://www.nmnh.si.edu/rtp/students/2006/images/oreska_advisor2.jpgMatthew Oreska
College of William and Mary
Williamsburg, Virginia

Matt Carrano, Ph.D.
Supervising Scientist
Department of Paleobiology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/oreska_poster.jpg
The terrestrial Early Cretaceous (ca. 121-98.9 MYA) of North America is represented by several formations that record a wide temporal and geographic range of environments and document major faunal changes between the Late Jurassic and the Late Cretaceous. However, relatively little is known about Early Cretaceous paleoecology. Vertebrate microfossil assemblages provide a promising means of addressing paleoecology by providing large, diverse samples of parautochthonous taxa. In this study, newly discovered microvertebrate samples from the Cloverly Formation are used to determine how the Cloverly ecosystem was constructed, whether Cloverly environments were uniform or heterogeneous, and how the Cloverly ecosystem compares with those of penecontemporaneous formations. Cloverly vertebrate microfossils were sorted into taxonomic and anatomical categories, and specimens were identified to the lowest possible taxonomic level. General anatomical and phylogenetic information were used to infer diet and habitat for each organism in the sample, allowing a broad examination of the paleoecology of each site. The identification of Cloverly microvertebrates greatly increased the known diversity of the Cloverly Formation and allowed preliminary paleoenvironmental and paleoecological reconstructions. The appearance of both terrestrially and aquatically dominated sites confirmed that the Cloverly Formation does record a heterogeneous environment, one with similarities to other Early Cretaceous formations. These similarities suggest that the Cloverly Formation records a representative North American Early Cretaceous fauna.

This research was supported by grants and donations to the Research Training Program.



A Study of Flying Squirrels of Southeast Asia (Sciuridae: Hylopetes)

http://www.nmnh.si.edu/rtp/students/2006/images/rasmussen_advisor1.jpgNick Rasmussen
Oklahoma State University
Stillwater, Oklahoma

Richard Thorington, Ph.D.
Supervising Scientist
Department of Zoology, Mammals

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/rasmussen_poster.jpg
For this project, a group of flying squirrels (genus Hylopetes) native to Southeast Asia was studied in an effort to work out the species and nomenclature. To address this problem, comparisons of skull morphometrics and pelage were made. It was found that Hylopetes lepidus is found in Java, and Hylopetes platyurus is found on the Malay Peninsula. Hylopetes spadiceus occurs on the Malay Peninsula and the animals on Sumatra and Borneo are most closely related to this species.

This research was supported by grants and donations to the Research Training Program.



Is Heterohelix rajagopalani the Ancestor of Gublerina cuvillieri? A Phylogenic and Taxonomic Study

http://www.nmnh.si.edu/rtp/students/2006/images/saupe_advisor1.jpgErin Saupe
St. John's University
St. John's, Minnesota

Brian Huber, Ph.D.
Supervising Scientist
Department of Paleobiology

http://www.nmnh.si.edu/rtp/students/2006/virtualposters/images/saupe_poster.jpg
Restructuring the classification of Cretaceous age planktonic foraminifer requires studying morphological changes through time and phylogenetic relationships between species. In the following study, Gublerina cuvillieri and its proposed ancestor Heterohelix rajagopalani were picked from Ocean Drilling Program Hole 761B (Exmouth Plateau), and their relationship was evaluated using biometric analyses and morphological observations from SEM images. The phylogenetic relationship between G. cuvillieri and H. rajagopalani has been the subject of some debate. Gublerina cuvillieri was first described by Kikoine (1948) from southern France, and Govindan (1972) described Gublerina rajagopalani from southern India. Nederbragt (1991) has since suggested that G. rajagopalani actually belongs in another genus, Heterohelix. In this study, quantitative data from x-ray image measurements provide evidence that H. rajagopalani is the direct ancestor of G. cuvillieri. The measurement data for the two species are virtually identical for the biserial portion of the tests, indicating a close phylogenetic relationship. Heterohelix rajagopalani and G. cuvillieri diverge later in their ontogenetic history as expressed in G. cuvillieri by separation of the serial chambers, development of a multiserial stage, greater chamber number, and concentration of ornamentation elements in bands extending around the chamber edge. Isotope data will reveal the two species’ depth ecologies and may provide future insight into the evolution of H. rajagopalani and G. cuvillieri.

This research was supported by grants and donations to the Research Training Program.



Evolution of the Lost World Mutisieae

http://www.nmnh.si.edu/rtp/students/2006/images/strahl_advisor1.jpgMaya Strahl
Berry College
Mount Berry, Georgia

Vicki Funk, Ph.D.
Supervising Scientist
Department of Botany

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The tribe Mutisieae is a member of the sunflower (Compositae) family and is now considered non-monophyletic. Many genera within the Mutisieae are restricted to high-elevation areas in the Guiana Shield, an ecologically and geologically distinct region in the northeastern corner of South America. Maps generated from information on labels of specimens collected in the Guiana Shield and published information were used to determine the distribution patterns of 13 genera and species from the four largest genera to see whether phylogenetic divisions within the group are supported. The results show that the Stenopadus group has a primarily eastern distribution pattern, whereas most members of the Gongylolepis group have a western distribution. These results support phylogenetic divisions based on molecular analyses, which have shown that these groups are not sister groups. One species in the Stenopadus group, Stenopadus talaumifolius, was the only species showing a widespread, high-elevation distribution, suggesting that the species needs further taxonomic study.

\This research was supported by grants and donations to the Research Training Program.



Inventory of the Butterflies (Hexapoda: Lepidoptera: Papilionidae, Pieridae, Lycaenidae, Nymphalidae, Hesperiidae) of Plummers Island, Maryland

http://www.nmnh.si.edu/rtp/students/2006/images/vann_advisor2.jpgKimberly Vann
University of Mary Washington
Fredericksburg, Virginia

John Brown, Ph.D.
Supervising Scientist
Department of Entomology

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A total of 35 species of butterflies were documented from Plummers Island, Maryland, based on four sources: transect survey (2006), diurnal collecting (2005), Malaise trap sampling (2005-2006), and historical records (1904-1997). Each of the four sources contributed species not recorded in the other three, demonstrating the importance of combining methods when inventorying fauna. Twenty-three species (66%) were observed on the transect survey, with six species not recorded in other sources. Nineteen species (54%) were captured during diurnal collecting, with seven species not recorded in other sources. Eight species (23%) were collected during Malaise trap sampling, with one species not recorded in other sources. Ten species (29%) were discovered in historical records, with three species not recorded in other sources.

This research was supported by grants and donations to the Research Training Program.

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