Life Sciences Commons^™

Exploring The Relationships Between Mammalian Functional Trait Distributions And Regional Biomes, With Application To Miocene Paleoecology, Devra Hock-Reid

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Paleoecology relies on understanding relationships between modern animals and their environment. Animals are adapted to niches in their environments, and those physical adaptations, or functional traits, are utilized as proxies to interpret aspects of paleo-ecosystems. Much is known about individual functional traits in extant mammals and their relationship to the environment. Less is known about how multiple functional traits across a community can be utilized for paleoecological interpretations. I develop models utilizing traits in mammalian communities at the biome level. For Chapter 1, I build a model for North American regional biomes using mammalian trait frequencies. I quantify changes in …

An Integrative Salt Marsh Conceptual Framework For Global Comparisons, Erik S. Yando, Scott F. Jones, W. Ryan James, Denise D. Colombano, Diana I. Montemayor, Stefanie Nolte, Jacqueline L. Raw, Shelby L. Ziegler, Luzhen Chen, Daniele Daffonchio, Marco Fusi, Kerrylee Rogers, Liudmila Sergienko

Biological Sciences Faculty Publications

Salt marshes occur globally across climatic and coastal settings, providing key linkages between terrestrial and marine ecosystems. However, salt marsh science lacks a unifying conceptual framework; consequently, historically well-studied locations have been used as normative benchmarks. To allow for more effective comparisons across the diversity of salt marshes, we developed an integrative salt marsh conceptual framework. We review ecosystem-relevant drivers from global to local spatial scales, integrate these multi-scale settings into a framework, and provide guidance on applying the framework using specific variables on 11 global examples. Overall, this framework allows for appropriate comparison of study sites by accounting for …

Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley

Electronic Theses and Dissertations

Turtles are important components of ecosystems around the world, with diverse ecological niches and adaptations. However, there are few detailed studies of how turtle community structure reflects local environments. This project applied techniques of community structure analysis to sites across the United States to infer past ecosystem and environmental conditions of the early Pliocene Gray Fossil Site (GFS) in northeastern Tennessee based on the ancient turtle community. Results indicate extant turtle community structure closely reflects environmental conditions, and that ancient turtle communities can be used to infer climate and habitat conditions of past ecosystems. Application to the GFS turtle community …

First Description Of Deep Benthic Habitats And Communities Of Oceanic Islands And Seamounts Of The Nazca Desventuradas Marine Park, Chile, Jan M. Tapia-Guerra, Ariadna Mecho, Erin E. Easton, María De Los Ángeles Gallardo, Matthias Gorny, Javier Sellanes

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Seamounts and oceanic islands of the Chilean Exclusive Economic Zone at the intersection of the Nazca and Salas y Gómez ridges lie within one of the least explored areas in the world. The sparse information available, mainly for seamounts outside Chilean jurisdiction and shallow-water fauna of the Desventuradas Islands, suggests that the area is a hotspot of endemism. This apparent uniqueness of the fauna motivated the creation of the large Nazca-Desventuradas Marine Park (NDMP, ~ 300,000 km2) around the small islands San Felix and San Ambrosio in 2015. We report for the first time a detailed description of benthic microhabitats …

Environmental Forcing On Zooplankton Distribution In The Coastal Waters Of The Galápagos Islands: Spatial And Seasonal Patterns In The Copepod Community Structure, Diego F. Figueroa

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The oceanographic setting of the Galápagos Archipelago results in a spatially diverse marine environment suitable for a variety of species with different climatic requirements. The goal of this study is to demonstrate that the community of zooplankton in the Galápagos is highly structured by regional differences in productivity patterns and advective sources. Results are mostly based on biodiversity patterns of the copepod community collected over the Galápagos shelf between 2004 and 2006. Two contrasting marine environments were observed: a nutrientrich upwelling system with a shallow mixed layer and a diatom-dominated phytoplankton community in the west, and a non-upwelling system with …

Environmental Controls On The Spatial Distribution Of Greenfin Darters And Biodiversity In The Blue Ridge Mountains, Dri Tattersfield

CMC Senior Theses

Disproportionate concentrations of biodiversity in mountains worldwide suggest linkages between geologic processes and biodiversity that are not yet well understood. The Tennessee River Basin in the Blue Ridge Mountains of the southeastern U.S. is a global hotspot for freshwater fish biodiversity. To investigate drivers of biodiversity in the Tennessee River Basin, and explore links to geologic processes, I study the Greenfin Darter (Nothonotus chlorobranchius), a small fish endemic to the upper Tennessee River Basin. I use generalized linear models (GLMs) to evaluate the influence of topography, lithology, climate and land use on the distribution of the Greenfin Darter, …

A Tale Of Two Species: Black-Tailed And White-Tailed Prairie Dog Biogeography From The Last Interglacial To 2070, April Dawn Bledsoe

Electronic Theses and Dissertations

Ecological niche models (ENMs) were created for White-tailed and Black-tailed prairie dogs and projected into the Last Interglacial (LI), the Last Glacial Maximum (LGM), and mid-Holocene (mid-H) to discern possible past suitable habitat for both species. Additionally, ENMs were projected into the future year 2070 representative concentration pathways (RCPs) 2.6 and 8.5 to discern how climate change may affect future habitat suitability. Kernel density estimations, minimum convex polygons, and median distribution centers of White-tailed and Black-tailed occurrence records were examined between time-periods to discern the effects of anthropogenic westward expansion on both species’ distributions. Current ENMs were constructed from commonly …

Architectonica Karsteni Rutsch, 1934 (Gastropoda: Architectonicidae) In Seamounts Of The Nazca-Desventuradas Marine Park: First Evidence Of An Extant Population In Chilean Waters Since The Miocene, Cynthia M. Asorey, Javier Sellanes, Erin E. Easton, Rüdiger Bieler, Ariadna Mecho

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The presence of Architectonicidae in Chile was previously recorded only from fossil material of eight species present during the Lower Miocene, when Architectonica karsteni had a geographic range that extended from Costa Rica to central Chile (34°S). No evidence of the presence of the family in Chile after the Lower Miocene have been reported. As part of this study, we report the discovery of A. karsteni at four seamountsat ~200 m water depth in the recently created Nazca-Desventuradas Marine Park, located ~900 km west of continental Chile. Morphological identification was based on protoconch diameter, coloration patterns, and teleoconch sculpture. We …

Eutherian Biogeography During The Puercan North American Land Mammal Age (Paleocene, Earliest Danian): Problems And Potential Solutions, Jason Sterling Silviria

Earth and Planetary Sciences ETDs

The Puercan North American Land Mammal Age (NALMA) is the earliest major North American terrestrial biochron of the Cenozoic era, spanning roughly the first one million years of the Paleogene period (Paleocene epoch, Danian stage; ~66.04-65.12 Ma). It is typified by the explosive ecomorphological diversification of the mammalian clade Eutheria (particularly our subclade, Placentalia), following the annihilation of non-avian dinosaurs and “archaic” mammal groups during the Cretaceous/Paleogene (K-Pg) mass extinction event. The spatiotemporal mode and tempo of Puercan eutherian diversification has long been the subject of debate, with disagreements over biogeographic zonation. The traditional model – based largely on well-sampled, …

Unexplored Diversity Of The Mesophotic Echinoderm Fauna Of The Easter Island Ecoregion, Ariadna Mecho, Erin E. Easton, Javier Sellanes, Matthias Gorny, Christopher Mah

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The Easter Island ecoregion (EIE) is one of the most remote marine areas of the world and encompasses a vast and fragile ecosystem including oceanic islands and seamounts. In January 2014 and March 2016, a remotely operated vehicle was used to explore a subsurface peak off Easter Island (27.23°S, 109.48°W) and a seamount (26.92°S, 110.26°W), respectively located 10 km southwest and 98 km west of the island. More than 950 echinoderms were observed in the 5 h of video recorded during the seven dives conducted at depths between ~ 160 and 280 m. The communities of echinoderms observed at these …

Climatic Range Filling Of North American Trees, Benjamin Seliger

Electronic Theses and Dissertations

Understanding the degree to which species distributions are controlled by climate is crucial for forecasting biodiversity responses to climate change. Climatic equilibrium, when species are found in all places which are climatically suitable, is a fundamental assumption of species distribution models, but there is evidence in support of climate disequilibria in species ranges. Long-lived, sessile organisms such as trees may be especially vulnerable to being outpaced by climate change, and thus prone to disequilibrium. In this dissertation, I tested the degree to which North American trees are in equilibrium with their potential climatic ranges using the ‘range filling’ metric, which …

The Functional And Distributional Ecology Of Mycetozoans Under Changing Edaphic And Climatic Dynamics, Geoffrey Lloyd Zahn

Graduate Theses and Dissertations

Investigations into the distribution and ecosystem functions of fruiting amoebae revealed that local-scale environmental conditions can largely explain broad biogeographical patterns in species assemblage, the way in which amoeboid predators shape bacterial communities and how this top-down influence may affect global biogeochemical processes in a changing climate. The distribution and assemblage of protosteloid amoebae on the islands of New Zealand and Hawaii did not yield any expected patterns of island biogeography, and conformed to other global regions studied. The strongest predictor of species richness in a given region was sampling effort and these species do not appear to have any …

Non-Anguimorph Lizards Of The Late Oligocene And Early Miocene Of Florida And Implications For The Reorganization Of The North American Herpetofauna, Kevin Chovanec

Electronic Theses and Dissertations

Paleokarst deposits from the Oligo-Miocene of northern Florida preserve undescribed herpetofaunal remains that fill important temporal and geographic gaps in our understanding of Cenozoic lizard evolution. Here I describe and discuss the non-anguimorph lizard diversity of the Brooksville 2 (Ar2) and Miller (He1) local faunas to test for patterns of regional and latitudinal provincialism in the contemporary North American record. Collectively, the sites are significant for documenting 1) extralimital occurrences of the tropical clades Anolis and Corytophaninae, 2) a substantial temporal range extension of the modern southeastern endemic Rhineuridae, 3) the earliest record of eublepharid gekkotans from North America, and …

Some Biogeographers, Evolutionists And Ecologists: Chrono-Biographical Sketches, Charles H. Smith, Joshua Woleben, Carubie Rodgers

DLPS Faculty Publications

Each name in the following list of naturalists is linked to a corresponding capsule "chrono-biographical" sketch of that individual prepared by the authors. Coverage extends from approximately 1950 backward in time as far as the eighteenth century; figures from all over the world are included (though there is admittedly a decided Anglo-American bias). The target subject here is biogeography, but this being a broad field there are many persons on the list who are better known as climatologists, zoologists, botanists, ecologists, oceanographers, paleontologists, etc.--in other words, who made their main reputations in cognate disciplines.

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Growth Of Chromidia-Forming Vahlkampfiid Amoebae From Laguna Figueroa, Baja California Del Norte, Mexico And Eel Pond, Woods Hole, Massachusetts, U.S.A. Under Limited Oxygen Gas Conditions, Melishia I. Santiago

Masters Theses 1911 - February 2014

Paratetramitus jugosus, a vahlkampfiid amoebomastigote, was isolated into monoprotist/monobacterial (Bacillus sp.), cultures from laminated microbial mats (Laguna Figueroa, Baja California Norte, Mexico) and muds (Eel Pond, Woods Hole, Massachusetts). Chromidia, roughly spherical (2-4 µm in diameter) were released from both walled spherical cysts (10-12 µm) and phagocytotic amoebic forms. Desiccation-resistant walled chromidia, at first spherical, resorb their walls and develop into small pleiomorphic phagocytotic amoeba. Small amoebae feed and mature into typical monopodial vahlkampfiid adults confirming previous work (Dobell, 1913, and especially the analysis of a larger encysting vahlkampfiid amoeba associated with Long Island oyster disease studied at Woods Hole …

Profiles In Science For Science Librarians: "What Lives Where, And Why": Alfred Russel Wallace, And The Field Of Biogeography, Charles H. Smith

DLPS Faculty Publications

Biogeography, the study of animal and plant distribution, has a history extending back to at least the eighteenth century. But it was not until the work of Charles Darwin and Alfred Russel Wallace in the mid-nineteenth century that it really came into its own as a science. Darwin’s importance notwithstanding, it was really Wallace who put the field on the map, and many of today’s research threads can be traced back to his influence. This article provides a summary review of Wallace’s life and work and biogeography as a field of study, including Wallace’s role in its development.

Oceanographic Conditions And Diversity Of Sea Stars (Echinodermata: Asteroidea) In The Gulf Of California, México, Carlos E. Cintra-Buenrostro, Hector Reyes-Bonilla, Maria Dinorah Herrero-Perezrul

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Species richness is one of the best indicators of biodiversity. However, there are few investigations on concordance of diversity patterns and environmental settings for marine regions. The objectives of this study were to correlate species richness of shallow water (< 200 m deep) sea stars with key oceanographic factors in the Gulf of California, México, and to predict species richness of Asteroidea using multiple regressions. In these analyses the Gulf was divided into nine sections of one degree in latitude (from 23 - 31° N), at each section we recorded: continental shelf area (at 100 and 200 m depth), temperature mean and range at three depth levels (0, 60 and 120 m), thermocline depth, surface nutrient concentrations (nitrates, phosphates and silicates), surface photosynthetic pigment concentration, and integrated productivity. Sea star species richness at each latitudinal section was estimated from literature data, new collections and museum records. Species were assigned to one of the following feeding guilds: predators of small mobile invertebrates (I), detritivores (D), predators of colonial organisms (C), generalist carnivores (G), and planktivores (P). There are 47 shallow water asteroid species in the Gulf of California (16 I, 15 D, eight C, six G, one P and one not assigned). Total species richness and guild species richness showed strong latitudinal attenuation patterns and were higher in the southernmost Gulf, an area characterized by a narrow shelf, high temperature, and low nutrient concentrations. Species diversity for each guild was correlated to a set of oceanographic parameters: temperature, nitrate concentration, and integrated productivity were linked to richness in must cases. We detected that nutrients and surface pigments always presented negative relationships with species richness, indicating that productive environments limit asteroid diversity in the study area. Finally, the postulated regression models to estimate species richness from oceanographic data were significant and highly precise. We conclude that species richness of Asteroidea in the Gulf of California is related to oceanographic conditions and can be estimated from regional oceanographic information.