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Distribution And Dispersal Potential Of The Endemic Tree Loblolly Bay (Gordonia Lasianthus) In The Southeastern United States Coastal Plain And Implications For Conservation In The Context Of Forecast Climate Scenarios., Herrick Hermann Klaus Brown

Theses and Dissertations

Plant communities in the Southeastern United States Coastal Plain constitute a rich assemblage of species from neighboring floristic provinces and include over 1,000 species endemic to the region. Conservation of these unique landscapes requires a better understanding of potential impacts from human activity and a changing climate. As a model species, the endemic tree Loblolly Bay (Gordonia lasianthus) is representative of Carolina Bays, pocosins, and isolated wetland habitats that accentuate Longleaf Pine ecosystems which dominate the focus area. Seed-dispersal events in Loblolly Bay are limited to periods of relatively low humidity primarily during the months of October to December, and …

Molecular Systematics Of Isoëtes (Isoëtaceae) In Eastern North America, Peter William Schafran

Biological Sciences Theses & Dissertations

Isoëtes (Isoëtaceae, Isoetales, Lycopodiophyta) is a cosmopolitan genus of aquatic lycophytes, occurring on every continent except Antarctica. Of approximately 200 total taxa, about half are in a clade of species mostly occurring in North and South America. Eastern North America accounts for 22% of global taxonomic diversity, containing 32 fertile taxa and 16 named hybrids. This taxonomic diversity is built upon relatively little morphological difference, and even combined with phylogenetic analysis using several nuclear and chloroplast DNA markers, no well-resolved systematic treatment within this clade exists.

This study aims to clarify the relationships between all species and subspecies of Isoëtes …

Temporal Changes In Abundance–Occupancy Relationships Over 40 Years, Lisa L. Manne, Richard R. Veit

Publications and Research

1. Abundance–occupancy (A–O) relationships are widely documented for many organismal groups and regions, and have been used to gain an understanding of regional population and community trends. Monitoring changes in abundance and occupancy over time may be what is required to document changes in conservation status and needs for some species, communities, or areas.
2. We hypothesize that if there is a higher proportion of declining species in one group of species compared with another (e.g., migratory species vs. permanent residents), then a consequence of that difference will be vastly different abundance–occupancy relationships. If this difference persists through time, then the resulting …

Remote Sensing Of Ploidy Level In Quaking Aspen (Populus Tremuloides Michx.), Benjamin Blonder, Bente J. Graae, Burke Greer, Marja Haagsma, Kenny Helsen, Rozália E. Kapás, Henry Pai, Jolanta Rieksta, Dillon Sapena, Christopher J. Still, Richard Strimbeck

Aspen Bibliography

1. Ploidy level in plants may influence ecological functioning, demography and response to climate change. However, measuring ploidy level typically requires intensive cell or molecular methods.
2. We map ploidy level variation in quaking aspen, a dominant North American tree species that can be diploid or triploid and that grows in spatially extensive clones. We identify the predictors and spatial scale of ploidy level variation using a combination of genetic and ground‐based and airborne remote sensing methods.
3. We show that ground‐based leaf spectra and airborne canopy spectra can both classify aspen by ploidy level with a precision‐recall harmonic mean of 0.75–0.95 and …

How The Atacama Skeleton Might Advance Discussion Of Responsible Conduct Of Research Responsibilities, Thomas May, Mariko Nakano-Okuno

Human Biology Open Access Pre-Prints

Controversies resulting from genetic testing on skeletal remains of disputed stewardship raise important questions about obligations inherent on genetic researchers to assure ethical chain of custody. In this paper, we analyze and evaluate several proposed positions on whether such research should be published. Following jurisprudential standards for legitimate regulatory systems, we argue that responsible conduct of research requires reasonable attention to chain of custody, but cannot require guarantees, particularly in cases of ancient remains.

Genetic Overview Of The Maya Populations: Mitochondrial Dna Haplogroups, Angélica González-Oliver, Dircé Pineda-Vázquez, Ernesto Garfias-Morales, Isabel De La Cruz-Laina, Luis Medrano-González, Lourdes Márquez-Morfín, Allan Ortega-Muñoz

Human Biology Open Access Pre-Prints

We identified the mitochondrial DNA haplogroups A, B, C and D in 75 present-day Maya individuals, 24 Maya individuals of the colonial period and one pre-Columbian Maya individual from Quintana Roo, Mexico. We examined these data together with those of 21 Maya populations accounting for 647 present-day Maya individuals and 104 ancient Maya individuals. A demographic study based on the analysis of fertility and endogamy was carried out in two modern Maya populations to identify cultural factors that influence the mitochondrial haplogroup genetic diversity. Most present-day and ancient Maya populations show a distribution pattern of mitochondrial haplogroup frequencies A, C, …

Timing Of Invasion By Africanized Bees Coincides With Local Extinction Of A Specialized Pollinator Of A Rare Poppy In Utah, Usa, Amber D. Tripodi, Vincent J. Tepedino, Zachary M. Portman

All PIRU Publications

The introduction of exotic species can have profound impacts on mutualisms between native species in invaded areas. However, determining whether a new invader has impacted native species depends on accurately reconstructing the invasion timing. The arrival of Africanized honey bees (AHB) in southern Utah at some point between 1994 and 2011 has recently been implicated in the local extinction of Perdita meconis, a native specialist pollinator of an endangered poppy, Arctomecon humilis. Although AHBs were purportedly first detected in southern Utah in 2008, their presence in nearby Nevada, Arizona, and New Mexico by 1998–2001 suggests that they may …

Genetic Variants Of Duffy And Hemoglobin S Genes In An Afrodescendent Population From Columbia, Diana C. Ortega, Heiber Cardenas, Guillermo Barreto

Human Biology Open Access Pre-Prints

Malaria is an endemic disease in a large part of Colombia, and the city of Buenaventura reports one of the highest malaria infection rates. Some genetic variants confer resistance to malaria, such as the heterozygote for hemoglobin S (HbS) and the homozygous variant FYB^ES/FYB^ES of the Duffy gene. The aim of this work was the molecular characterization of these genes in an afrodescendent population from the urban area of Buenaventura. A total of 819 individuals from a stratified random sampling in each of the 12 communities of this city were analysed. Molecular analysis was performed using PCR-RFLP, …

Ontogenesis Of The Sella Turcica Among Egyptians: Forensic And Radiological Study, Wafaa Mohamed El-Sehly, Fatma Mohamed Magdy Badr El Dine, Mohamed Samir Shaban

Human Biology Open Access Pre-Prints

Introduction: The sella turcica has gained importance as a stable bony landmark in cephalometric studies.
Aim of the work: The aim of the work was to explore the changes that accompany postnatal ontogeny of the sella turcica until full development, and to verify its contribution in age estimation and sexual assignment among Egyptians.
Subjects and methods: Six selected measurements of the sella turcica of 215 Egyptian patients were assessed using Multidetector Computed Tomography (MDCT). The patients represented different ages and were referred to the Radiodiagnosis and Intervention Department. The gathered data were then subjected to statistical analysis including correlation and …

Complexity, Genetic Causation, And Hereditarianism, Charles Roseman

Human Biology Open Access Pre-Prints

Hereditarians have claimed that recent advances in psychological and psychiatric genetics support their contention that individual and group socially important aspects of behavior and cognition are largely insensitive to environmental context. This has been countered by anti- hereditarians who (correctly) claim that the conclusion of genetic ineluctability is false. Anti- hereditarians, however, sometimes use problematic arguments based on complexity and the ignorance that comes with complexity and a demand for mechanistic, as opposed to variational, explanations for the ways in which genes affect phenotype. I argue here, as a committed anti-hereditarian, that the complexity gambit and the demand for mechanisms …

Worldwide Relationships In The Fern Genus Pteridium (Bracken) Based On Nuclear Genome Markers, Paul G. Wolf, Carol A. Rowe, Sylvia P. Kinosian, Joshua P. Der, Peter J. Lockhart, Lara D. Shepherd, Patricia A. Mclenachan, John A. Thomson

Ecology Center Publications

PREMISE: Spore-bearing plants are capable of dispersing very long distances. However, it is not known if gene flow can prevent genetic divergence in widely distributed taxa. Here we address this issue, and examine systematic relationships at a global geographic scale for the fern genus Pteridium.

METHODS: We sampled plants from 100 localities worldwide, and generated nucleotide data from four nuclear genes and two plastid regions. We also examined 2801 single nucleotide polymorphisms detected by a restriction site-associated DNA approach.

RESULTS: We found evidence for two distinct diploid species and two allotetraploids between them. The “northern” species (Pteridium aquilinum) has distinct …

Reorganization Of Surviving Mammal Communities After The End-Pleistocene Megafaunal Extinction, Anikó B. Tóth, S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis, Andrew Du, Jussi T. Eronen, J. Tyler Faith, Danielle Fraser, Nicholas J. Gotelli, Gary R. Graves, Advait M. Jukar, Joshua H. Miller, Silvia Pineda-Munoz, Laura C. Soul, Amelia Villaseñor, John Alroy

School of Biological Sciences: Faculty Publications

Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end- Pleistocene megafaunal extinction in North America.We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on cooccurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, …

Precipitation Mediates Sap Flux Sensitivity To Evaporative Demand In The Neotropics, Charlotte Grossiord, Bradley O. Christoffersen, Aura M. Alonso-Rodríguez, Kristina Anderson-Teixeira, Heidi Asbjornsen, Luiza Maria T. Aparecido, Z. Carter Berry, Christopher Baraloto, Damien Bonal, Isaac Borrego

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Transpiration in humid tropical forests modulates the global water cycle and is a key driver of climate regulation. Yet, our understanding of how tropical trees regulate sap flux in response to climate variability remains elusive. With a progressively warming climate, atmospheric evaporative demand [i.e., vapor pressure deficit (VPD)] will be increasingly important for plant functioning, becoming the major control of plant water use in the twenty-first century. Using measurements in 34 tree species at seven sites across a precipitation gradient in the neotropics, we determined how the maximum sap flux velocity (vmax) and the VPD threshold at which …

Plasticity Of Foot Muscle And Cardiac Thermal Limits In The Limpet Lottia Limatula From Locations With Differing Temperatures, Terrance Wang, Richelle L. Tanner, Eric J. Armstrong, David R. Lindberg, Jonathon H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Species distributions are shifting in response to increased habitat temperatures as a result of ongoing climate change. Understanding variation in physiological plasticity among species and populations is important for predicting these distribution shifts. Interspecific variation in intertidal ectotherms’ short-term thermal plasticity has been well established. However, intraspecific variation among populations from differing thermal habitats remains a question pertinent to understanding the effects of climate change on species’ ranges. In this study, we explored upper thermal tolerance limits and plasticity of those limits using a foot muscle metric and 2 cardiac metrics (Arrhenius breakpoint temperature, ABT, and flatline temperature, FLT) in …

Red Oak Seedlings As Indicators Of Deer Browse Pressure: Gauging The Outcome Of Different White-Tailed Deer Management Approaches, Bernd Blossey, Paul Curtis, Jason Boulanger, Andrea Davalos

Biology Faculty Publications

After decades of high deer populations, North American forests have lost much of their previous biodiversity. Any landscape‐level recovery requires substantial reduc‐ tions in deer herds, but modern societies and wildlife management agencies appear unable to devise appropriate solutions to this chronic ecological and human health crisis. We evaluated the effectiveness of fertility control and hunting in reducing deer impacts at Cornell University. We estimated spring deer populations and planted Quercus rubra seedlings to assess deer browse pressure, rodent attack, and other factors compromising seedling performance. Oak seedlings protected in cages grew well, but deer annually browsed ≥60% of unprotected …

Environmentally Responsible Land Use, Spring/Summer 2010, Issue 22

Sustain Magazine

No abstract provided.

Sustainable Communities, Fall/Winter 2010, Issue 21

Sustain Magazine

No abstract provided.

Sustainable Building, Spring/Summer 2009, Issue 20

Sustain Magazine

No abstract provided.

Environmental History, Fall/Winter 2009, Issue 19

Sustain Magazine

No abstract provided.

Student Research, Spring/Summer 2008, Issue 18

Sustain Magazine

No abstract provided.

Evolving Pollution Prevention, Fall/Winter 2008, Issue 17

Sustain Magazine

No abstract provided.

Climate Change, Spring/Summer 2007, Issue 16

Sustain Magazine

No abstract provided.

Our Energy Future, Fall/Winter 2007, Issue 15

Sustain Magazine

No abstract provided.

Land Conservation, Spring/Summer 2006, Issue 14

Sustain Magazine

No abstract provided.

Pollution And Heart Disease, Fall/Winter 2006, Issue 13

Sustain Magazine

No abstract provided.

Green Cities, Spring/Summer 2005, Issue 12

Sustain Magazine

No abstract provided.

Global Sustainability, Fall/Winter 2005, Issue 11

Sustain Magazine

No abstract provided.

Environmental Justice, Spring/Summer 2004, Issue 10

Sustain Magazine

No abstract provided.

Kentucky's Environmental Future, Fall/Winter 2004, Issue 9

Sustain Magazine

No abstract provided.

Urban Ecology, Spring/Summer 2003, Issue 8

Sustain Magazine

No abstract provided.