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Full-Text Articles in Physical Sciences and Mathematics

Analyzing The Shark Paleoecology Of Coastal Georgia From The Miocene And Pliocene Epochs, Joshua Lee Clark, Benjamin Angalet Dec 2023

Analyzing The Shark Paleoecology Of Coastal Georgia From The Miocene And Pliocene Epochs, Joshua Lee Clark, Benjamin Angalet

Georgia Journal of Science

The field of shark paleoecology often yields indecisive conclusions based on the limited fossilization of their anatomical structures, with the exception of their teeth. The majority of the Atlantic coast has been studied regarding the presence of certain prehistoric shark species from the Miocene, Pliocene, and Pleistocene epochs. However, information pertaining to the Georgia coast and understanding its potential community structure is relatively understudied. This study was conducted in which thousands of fossil shark specimens and subsequent marine fauna were collected from dredge spoils created by the US Army Corps of Engineers (USACE): Savannah District. A total of 5,127 fossil …


Ecological Controls On The Campanian Distribution Of Hesperornis (Aves: Hesperornithiformes) In The Western Interior Seaway, Blake Chapman Jan 2021

Ecological Controls On The Campanian Distribution Of Hesperornis (Aves: Hesperornithiformes) In The Western Interior Seaway, Blake Chapman

Master's Theses

The epicontinental Western Interior Seaway (WIS) of Late Cretaceous North America provided a unique marine habitat for cephalopods, fish, marine reptiles, and the foot-propelled diving seabird Hesperornis. While several predator-prey relationships among Hesperornis or other hesperornithiforms and other WIS animals have been hypothesized based on gut contents, bite marks, and coprolites/colonites, ecological relationships have not been quantitatively tested. Paleontological species distribution modeling (SDM) studies have focused on extinct non-marine taxa and marine invertebrates, with only two marine vertebrate studies of extant taxa. Here, two SDM methods were used to test the influence of vertebrate faunas, sedimentary rock type, paleogeography, …


Accessible Science: The Natural History Of The Connecticut River Valley, Fred Venne Jan 2019

Accessible Science: The Natural History Of The Connecticut River Valley, Fred Venne

Science and Engineering Saturday Seminars

Many students take an Earth science or geology course to fulfill a requirement, knowing little to nothing about the field. Like all sciences, geology can appear to have ready answers unconnected to other areas of human endeavor, such as art, religion or philosophy. An interdisciplinary approach to teaching can ameliorate this perception for students who are intimidated by the subject and deepen understanding for those who are already excited about geology. We will examine two strategies designed to support the nature of science while scaffolding student learning in geology: research based digital resources use and museum of natural history visits. …


Encrusting Sclerobiont Paleoecology And Bioerosion Of Oysters In The Type Campanian (Upper Cretaceous) Of Southwestern France, Macy A. Conrad Jan 2018

Encrusting Sclerobiont Paleoecology And Bioerosion Of Oysters In The Type Campanian (Upper Cretaceous) Of Southwestern France, Macy A. Conrad

Senior Independent Study Theses

The Campanian Stage of the Upper Cretaceous was established by Henri Coquand in 1857 based on a sequence of richly fossiliferous shallow water carbonates in the Charente and Charente-Maritime departments of southwestern France. One of the most common macrofossils is the gryphaeid oyster Pycnodonte vesicularis (Lamarck, 1806), which often forms extensive shell beds. This bivalve lived primarily on soft marly substrates, forming hard substrate islands. They frequently supported sclerobiont communities comprising encrusters (diverse cheilostome and cyclostome bryozoans, foraminiferans, oysters, bivalves, sabellid and serpulid polychaetes, calcareous sponges), borers (the sponge borings Entobia, the worm borings Maeandropolydora and Caulostrepsis, the barnacle borings …


Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson Mar 2017

Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson

Faculty Publications

Texas Academy of Science, 2017 Field Trip

This year's Texas Academy of Science Geology Field Trip takes you to two very different fossil sites in central Texas. Stop 1 is along a quiet road in the Hill Country where you can collect abundant invertebrate fossils from the Lower Cretaceous Comanche Peak Limestone and Walnut Clay. The second stop of the trip is at one of the newest units of America's park service: the Waco Mammoth National Monument. At this site you will see a spectacular fossil discovery that is now one of the main mammoth sites in North America. And …


New Early Miocene 40ar/39ar Ages For Nakwai, Northwest Kenya, Africa, And Paleontological Analysis Of Meroehyrax Kyongoi Dentition, Dawn Elena Reynoso Dec 2014

New Early Miocene 40ar/39ar Ages For Nakwai, Northwest Kenya, Africa, And Paleontological Analysis Of Meroehyrax Kyongoi Dentition, Dawn Elena Reynoso

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nakwai is a fossiliferous region in the Turkana Basin of northwestern Kenya. Until recently the only ages for the Nakwai formation were based on biostratigraphic correlation with Losodok; a late Oligocene site located to the north of Nakwai. The new 40Ar/39Ar ages in this study range from 23 Ma to 15 Ma and constrain the upper portions of the Nakwai section to the early Miocene. These ages make it the only securely dated fossil locality in the region that represents the earliest Miocene; all of the other early Miocene fossil localities date back to ~20 Ma or younger. The time …


Exhumation Of The Baranof Schist In Whale Bay Alaska Determined Through Zircon Fission Track Dating, Kate Kaminski Jun 2014

Exhumation Of The Baranof Schist In Whale Bay Alaska Determined Through Zircon Fission Track Dating, Kate Kaminski

Honors Theses

During the Eocene in the North Pacific, the Kula, Farallon, and Pacific plates met in a trench-ridge-trench triple junction, bordered to the east by a continental margin along the edge of the North American plate. The flysch of the Chugach-Prince William terrane, a deformed accretionary complex, accreted onto this margin in the late Cretaceous to Paleocene. This terrane is framed to the north by the Border Ranges fault, a large strike-slip fault system that has accommodated northward movement of the Chugach-Prince William since the Eocene. One of the easternmost units of the Chugach-Prince William is the Baranof Schist on Baranof …


Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller Dec 2013

Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study I describe and interpret tracks and trackways of the Jurassic Aztec Sandstone of southern Nevada and southern California. This study involved mapping of all known tracks and trackways, including foot length, stride length, and trackway width. Photogrammetric data, collected by Bureau of Land Management scientists, were utilized for several trackways in Red Rock Canyon National Conservation Area.

More than three hundred tracks belonging to five ichnotaxa were documented within the Aztec Sandstone, including about 165 tridactylGrallator, 250 tetradactyl (four-toed)Brasilichniumtracks, and 7 arthropod trackways ofOctopodichnusandPaleohelcura. Four of the five ichnotaxa were not previously reported from the Aztec Sandstone. …


W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks Apr 2008

W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks

Faculty Publications

A major challenge in the post-genomics era will be to integrate molecular sequence data from extant organisms with morphological data from fossil and extant taxa into a single, coherent picture of phylogenetic relationships; only then will these phylogenetic hypotheses be effectively applied to the study of morphological character evolution. At least two analytical approaches to solving this problem have been utilized: (1) simultaneous analysis of molecular sequence and morphological data with fossil taxa included as terminals in the analysis, and (2) the molecular scaffold approach, in which morphological data are analyzed over a molecular backbone (with constraints that force extant …


W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks Mar 2008

W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks

Jonathan R. Hendricks

A major challenge in the post-genomics era will be to integrate molecular sequence data from extant organisms with morphological data from fossil and extant taxa into a single, coherent picture of phylogenetic relationships; only then will these phylogenetic hypotheses be effectively applied to the study of morphological character evolution. At least two analytical approaches to solving this problem have been utilized: (1) simultaneous analysis of molecular sequence and morphological data with fossil taxa included as terminals in the analysis, and (2) the molecular scaffold approach, in which morphological data are analyzed over a molecular backbone (with constraints that force extant …


Complexity Trends In The Evolutionary History Of Dasycladalean Algae, Michael Stearns Jan 2006

Complexity Trends In The Evolutionary History Of Dasycladalean Algae, Michael Stearns

Senior Honors Theses and Projects

Dasycladalean algae are a group of marine algae that have an excellent fossil record extending back more than 500 million years. In our study, we investigated morphological complexity over the evolutionary history of this group. To determine complexity for each of more than 400 species, we assigned numerical values for six morphological features; the sum for each species forms a quantitative expression of complexity. We found that although maximum complexity increased over time, forms with minimum complexity persisted during most of the evolutionary history of the group.


Middle Eocene Foraminifera From The Piney Point Formation Of The Virginia And Maryland Coastal Plain, Megan S. Jones Jan 1990

Middle Eocene Foraminifera From The Piney Point Formation Of The Virginia And Maryland Coastal Plain, Megan S. Jones

OES Theses and Dissertations

This study examines the foraminiferal fauna, both benthic and planktonic, of the outcropping (45 samples) and subsurface (31 samples) middle Eocene Piney Point Formation in Virginia and Maryland. The primary objective of this study is to further refine the depositional history of the Salisbury Embayment which is represented by the middle Eocene Piney Point Formation. Ninety-six species of benthic and planktonic foraminifera were identified in this study. Of these, several are characteristic of the middle Eocene: Asterigerina texana, Hanzawaia danvillensis, Ceratobulimina exima, Cibicides westi, Chiloguembelitria columbiana, C. stavensis, Testacarinata inconspicua and Pseudohastigerina wilcoxensislmicra. While these were relatively abundant, diagnostic middle …


Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen Jan 1989

Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen

Honors Papers

Our understanding of the structure and function of biological systems can be increased when viewed in the context of their evolutionary history on a geological time scale. Generally, both paleoecology and ecology have focused on the interrelationships of organisms and their environments in short time frames. For instance, a paleoecologist might study the fossil communities of the Columbus Limestone reefal environment at Marblehead, Ohio, or an ecologist might attempt to characterize the interrelationship of glacier lilies and their pollinators. Both workers may realize that the organisms they study evolved in response to ecological pressures, yet neither, most likely, considers that …


Recent Benthic Foraminifera Of Breton And Stake Islands Northern Gulf Of Mexico, Eric S. Collins Oct 1988

Recent Benthic Foraminifera Of Breton And Stake Islands Northern Gulf Of Mexico, Eric S. Collins

OES Theses and Dissertations

Fifty-three species of recent benthic foraminifera and thecamoebians have been documented and described from the Breton and Stake Island area, northern Gulf of Mexico, and from a core from Barataria Basin, Mississippi delta.

Cluster analysis of benthic assemblages using presence/absence and transformed abundance data reveals the presence of a marsh and shallow water marine biofacies. Based on the results of a presence/absence cluster analysis, the shallow water marine biofacies can be subdivided into a miliolid biofacies am an Ammonia beccarii/Elphidium species biofacies. Cluster analysis of transformed abundance data, however, shows that the shallow marine biofacies can be subdivided into four …


Foraminiferal Paleoenvironments Of The Eastover Formation (Upper Miocene Virginia), Joann H. Goshorn Apr 1985

Foraminiferal Paleoenvironments Of The Eastover Formation (Upper Miocene Virginia), Joann H. Goshorn

OES Theses and Dissertations

Sixty-two taxa representing 29 genera from 39 foraminiferal sample pairs have been documented and analyzed in a paleoenvironmental study of the Eastover Formation in southeastern Virginia. The Eastover Formation consists of a lower Claremont Manor Member, a silt fine-grained sand and an upper Cobham Bay Member, a shelly fine grained sand. Planktonic specimens were rare and indicated a late Miocene to early Pliocene age for the Eastover Formation. Benthics were used to interpret paleoenvironments by comparison with data from the distribution of Recent foraminifera, species diversity, planktonic to benthic ratios, and sediment analyses. The foraminifera indicate that the Eastover Formation …


Late Quaternary Environmental And Climatic History Of The Southern Chilean Lake Region Interpreted From Coleopteran (Beetle) Assemblages, John W. Hoganson Jan 1985

Late Quaternary Environmental And Climatic History Of The Southern Chilean Lake Region Interpreted From Coleopteran (Beetle) Assemblages, John W. Hoganson

Theses and Dissertations

A diverse Coleoptera fauna of 462 species in 48 families was collected from 41 locations in the Parque Nacional de Puyehue and adjacent parts of the Lake Region of southern Chile. The sample locations ranged from rain forest habitats at sea-level to Andean tundra habitats at 1500 m msl. Cluster analysis of a Dice similarity coefficient matrix revealed a broad pattern of bioassociations within the large data base, Boundaries between the bioassociations correspond largely with those of the major vegetation zones implying that the distribution of the fauna is strongly influenced by the distribution of plants. Evidence from fossils indicates …


Gastropoda Of The Fox Hills Formation (Maestrichtian) Of North Dakota, J. Mark Erickson Jan 1971

Gastropoda Of The Fox Hills Formation (Maestrichtian) Of North Dakota, J. Mark Erickson

Theses and Dissertations

The Fox Hills Formation (Maestrichtian, Upper Cretaceous) in North Dakota contains a gastropod fauna of thirty-seven species. Five species, loganensis n. sp., Piestochilus feldmanni n. sp., Hercorhyncus (Hercorhyncus) hollandi n. sp., cvancarai n. sp., and Cancellaria siouxensis n. sp. , and genus, Dakotia, are newly described. Twenty-four genera in eighteen families representing four orders and two subclasses of Gastropoda are present. Eleven species in a like number of genera are newly reported from the Fox Hills For mation. Goniocylichna bisculnturata and rectilabrum occur in common with the gastropod fauna of the Ripley Formation of the Mississippi Embayment, which has the …


Gastropoda From The Pierre Shale (Upper Cretaceous) Of Emmons County, South-Central North Dakota, Alan M. Cvancara Jan 1957

Gastropoda From The Pierre Shale (Upper Cretaceous) Of Emmons County, South-Central North Dakota, Alan M. Cvancara

Theses and Dissertations

Fossil gastropods were studied from the upper part of the Pierre shale (Upper Cretaceous) in Emmons County, south-central North Dakota. This primary purpose of this study was to figure all gastropods found and bring the nomenclature of up to date. Secondly, an attempt was made to determine whether these fossil gastropods could be used in defining the contact between the Pierre shale and overlying Fox Hills sandstone.

Little paleontological work has been done on Pierre gastropods in North Dakota. Identification previously made seem to have been done somewhat hurriedly from Meek (1876) with little regard to modernizing the nomenclature.

These …


Life History Of The Ginko Petrified Forest Or The Autobiography Of An Ancient Oak Tree, George F. Beck Jan 1939

Life History Of The Ginko Petrified Forest Or The Autobiography Of An Ancient Oak Tree, George F. Beck

Geological Sciences Faculty Scholarship

An account of a fossilized log at Ginkgo Tree State Park written by the man who discovered the fossil trees and established there were Ginkgo trees in North America in the distant past.

The booklet is written from the perspective of one of the fossilized trees, tracing the geologic forces that led to it becoming a fossil.


Siliceous Sponge Spicules Of The Quadrant Formation From Montana., Lester Zeihen May 1935

Siliceous Sponge Spicules Of The Quadrant Formation From Montana., Lester Zeihen

Bachelors Theses and Reports, 1928 - 1970

A sponge spicule is a siliceous or calcareous individual or group of rays which form a framework for the sponge. Sponge spicules are very delicate and easily broken. The methods used in obtaining micro-fossils vary considerably with the type of material from which they are to be recovered and the frailness of the fossil obtained.


A Description Of Two New Fossil Fungi, A. C. Whitford Jan 1916

A Description Of Two New Fossil Fungi, A. C. Whitford

Conservation and Survey Division

No abstract provided.


A New Mount Of The Fossil Tortoise, "Testudo Orthopygia", E. H. Barbour Jan 1915

A New Mount Of The Fossil Tortoise, "Testudo Orthopygia", E. H. Barbour

Conservation and Survey Division

No abstract provided.


A New Fossil Horse, "Hypohippus Matthewi", E. H. Barbour Jan 1914

A New Fossil Horse, "Hypohippus Matthewi", E. H. Barbour

Conservation and Survey Division

No abstract provided.


Two New Fossil Dogs Of The Genus "Crynarctus" From Nebraska, E. H. Barbour Jan 1914

Two New Fossil Dogs Of The Genus "Crynarctus" From Nebraska, E. H. Barbour

Conservation and Survey Division

No abstract provided.


Notice Of A New Fossil Rhinoceros From Sioux County Nebraska, Erwin Hinckley Barbour Jan 1906

Notice Of A New Fossil Rhinoceros From Sioux County Nebraska, Erwin Hinckley Barbour

Conservation and Survey Division

No abstract provided.