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Prospecting For Mammalian Chemical Signals Via Solventless Extraction Techniques: An Elephantine Task, Thomas Goodwin, Bruce A. Schulte Jan 2009

Prospecting For Mammalian Chemical Signals Via Solventless Extraction Techniques: An Elephantine Task, Thomas Goodwin, Bruce A. Schulte

Biology Faculty Publications

In contrast to a plethora of known insect pheromones, a paucity of mammalian pheromones has been identified, two of which have been in elephants (Albone, 1984; Brown and Macdonald, 1985; Wyatt, 2003; Burger, 2005). Elephants possess one of the world’s best chemosensory systems, due in no small measure to their prehensile trunk. The trunk is not only the gateway to smelling (primary olfaction), but also the means by which chemical signals are conveyed from their source to the openings of the vomeronasal organ ducts in the roof of the mouth (the flehmen response; secondary olfaction) (Rasmussen, 1999). The late L. …


What's In A Word? On Reading--And Misreading--Alfred Russel Wallace, Charles H. Smith Jan 2009

What's In A Word? On Reading--And Misreading--Alfred Russel Wallace, Charles H. Smith

DLPS Faculty Publications

No abstract provided.


Behavioral Explanations Underlying The Lack Of Trap Effectiveness For Small-Scale Management Of Japanese Beetles (Coleoptera: Scarabaeidae), Paul V. Switzer, Patrick C. Enstrom, Carissa A. Schoenick Jan 2009

Behavioral Explanations Underlying The Lack Of Trap Effectiveness For Small-Scale Management Of Japanese Beetles (Coleoptera: Scarabaeidae), Paul V. Switzer, Patrick C. Enstrom, Carissa A. Schoenick

Faculty Research & Creative Activity

Traps containing a combination floral and synthetic pheromone lure are used to monitor and manage Japanese beetles, Popillia japonica Newman (Coleoptera: Scarabaeidae). One key factor limiting trap effectiveness for beetle control is the "trap spillover" phenomenon, in which the trap attracts beetles without capturing them, resulting in increased damage to surrounding host plants. We investigated the mechanisms underlying trap spillover by conducting two studies in a soybean field in east central Illinois. In the first study, we set up trap stations for 1 d and compared the sex, size, and egg load (for females) of beetles caught in the traps …


Behavioral Explanations Underlying The Lack Of Trap Effectiveness For Small-Scale Management Of Japanese Beetles (Coleoptera: Scarabaeidae), Paul Switzer, Patrick Enstrom, Carissa Schoenick Jan 2009

Behavioral Explanations Underlying The Lack Of Trap Effectiveness For Small-Scale Management Of Japanese Beetles (Coleoptera: Scarabaeidae), Paul Switzer, Patrick Enstrom, Carissa Schoenick

Faculty Research & Creative Activity

Traps containing a combination floral and synthetic pheromone lure are used to monitor and manage Japanese beetles, Popillia japonica Newman (Coleoptera: Scarabaeidae). One key factor limiting trap effectiveness for beetle control is the "trap spillover" phenomenon, in which the trap attracts beetles without capturing them, resulting in increased damage to surrounding host plants. We investigated the mechanisms underlying trap spillover by conducting two studies in a soybean field in east central Illinois. In the first study, we set up trap stations for 1 d and compared the sex, size, and egg load (for females) of beetles caught in the traps …


Distress Or Suffering: What Should Be Measured To Determine Animal Well-Being?, Ian J. H. Duncan Jan 2009

Distress Or Suffering: What Should Be Measured To Determine Animal Well-Being?, Ian J. H. Duncan

Sentience Collection

It is generally accepted that all the vertebrates and some of the invertebrates (those with large neural ganglia such as the cephalopods) are capable of subjective experiences. Amongst those experiences are the subjective, affective states, sometimes called 'feelings' or 'emotions'. The strong negative feelings are often lumped together as 'suffering' and the positive feelings as 'pleasure'. I have argued for many years that animal welfare/well-being is completely dependent on what the animal feels (Duncan, 1993, 1996, 2002). An animal's well-being is decreased by experiencing suffering and increased by experiencing pleasure. It's as simple as that.


Distress In Animals: Its Recognition And A Hypothesis For Its Assessment, David B. Morton Jan 2009

Distress In Animals: Its Recognition And A Hypothesis For Its Assessment, David B. Morton

Sentience Collection

This essay deals with the recognition of non-painful emotional experiences in animals, how they relate to animal wellbeing and animal welfare, and how they can be assessed, monitored and mitigated. While it is written often from a mammalian perspective, the general principles will apply to all animals that are sentient.


What Is New On The Animal Protection Radar?, John Hadidian Jan 2009

What Is New On The Animal Protection Radar?, John Hadidian

Animal Welfare Collection

American attitudes toward wildlife have often been cast as falling within an urban/rural dichotomy that separates protectionist from utilitarian value orientations. Long held as a major challenge to wildlife managers the urban/rural dichotomy may be yielding to change as new attitude and value orientations arise from direct conflicts people have with wild animals as well as from a generational disenfranchisement of young people who lack direct experience with the outdoors. Both may loom as larger challenges for the future and shift the focus of once opposing interests more toward efforts to establish cooperation. Currently, much of the disagreement over wildlife …


Welfare Assessment: Correlations And Integration Between A Qualitative Behavioural Assessment And A Clinical/Health Protocol Applied In Veal Calves Farms, Marta Brscic, Françoise Wemelsfelder, Elena Tessitore, Flaviana Gottardo, Giulio Cozzi, Cornelis G. Van Reenen Jan 2009

Welfare Assessment: Correlations And Integration Between A Qualitative Behavioural Assessment And A Clinical/Health Protocol Applied In Veal Calves Farms, Marta Brscic, Françoise Wemelsfelder, Elena Tessitore, Flaviana Gottardo, Giulio Cozzi, Cornelis G. Van Reenen

Agribusiness Collection

This study is aimed at finding correlations and possible integration among Qualitative Behavioural assessment (QBA) and a specific protocol of clinical/health evaluation. Both welfare assessment methods were based on direct animal observation and were applied in 24 Italian veal calves farms at 3 weeks (wks) of rearing. Principal component analysis (PCA) summarized 20 QBA descriptors on two main components (PC1 and PC2) with eigenvalues above 4 and explaining 29.6 and 20.3% of the variation respectively. PCA on residuals obtained after correcting for housing condition yielded highly similar results, indicating that the rearing environment of the calves was not an important …


Resources, Not Kinship, Determine Social Patterning In The Territorial Gunnison’S Prairie Dog (Cynomys Gunnisoni), J. L. Verdolin, C. N. Slobodchikoff Jan 2009

Resources, Not Kinship, Determine Social Patterning In The Territorial Gunnison’S Prairie Dog (Cynomys Gunnisoni), J. L. Verdolin, C. N. Slobodchikoff

Sentience Collection

In this study, we describe patterns of relatedness in Gunnison’s prairie dog (Cynomys gunnisoni) social groups. Kin selection is often cited as a mechanism for the evolution and maintenance of social groups, and Gunnison’s prairie dog females are occasionally described as being strongly philopatric. Overall, randomization tests revealed that females within territorial groups were not more closely related to each other than expected at random. A similar pattern was found among males and between males and females, indicating that there was no sex-biased dispersal occurring in these populations. Ecological variables measured in this study, such as food abundance and food …


Landscape Heterogeneity And Marine Subsidy Generate Extensive Intrapopulation Niche Diversity In A Large Terrestrial Vertebrate, Chris T. Darimont, Paul C. Paquet, Thomas E. Reimchen Jan 2009

Landscape Heterogeneity And Marine Subsidy Generate Extensive Intrapopulation Niche Diversity In A Large Terrestrial Vertebrate, Chris T. Darimont, Paul C. Paquet, Thomas E. Reimchen

Population Distribution and Habitat Collection

1 Inquiries into niche variation within populations typically focus on proximate ecological causes such as competition. Here we examine how landscape heterogeneity and allochthonous (marine) subsidy might ultimately generate intrapopulation niche diversity.

2 Using stable isotope analysis, we detected extensive terrestrial–marine isotopic niche variation among subpopulations, social groups, and individual grey wolves (Canis lupus) that occupy a spatially heterogeneous landscape in coastal British Columbia comprising a mainland area and adjacent archipelago.

3 The inner island subpopulation exhibited the widest isotopic niche in the population, consuming extensive terrestrial and marine resources. Mainland and outer island subpopulations occupied comparatively narrow …


A Study Of The Morphology Of Tatenectes Laramiensis, A Cryptocleidoid Plesiosaur From The Sundance Formation (Wyoming, Usa), Hallie P. Street Jan 2009

A Study Of The Morphology Of Tatenectes Laramiensis, A Cryptocleidoid Plesiosaur From The Sundance Formation (Wyoming, Usa), Hallie P. Street

Theses, Dissertations and Capstones

Tatenectes laramiensis is a cryptocleidoid plesiosaur from the Late Jurassic Sundance Formation. This study primarily concerns a partial skeleton comprised of dorsal vertebrae, ribs, gastralia, and pelvic girdle. Even though the skeleton is incomplete, it is hypothesized that the preserved fossils are sufficient to indicate the overall body shape and also the preferred habitat of Tatenectes. Possibly the most notable of the novel characters is the pachyostotic state of the gastralia. In relation to the ribs and overall size of Tatenectes, in comparison to the gastralia in related taxa, these gastralia are disproportionately robust. The combination of these morphologies suggests …


Geographic Distribution: Hemidactylus Mabouia (Wood Slave). Usa: Florida: St. Lucie Co., Louis A. Somma Jan 2009

Geographic Distribution: Hemidactylus Mabouia (Wood Slave). Usa: Florida: St. Lucie Co., Louis A. Somma

Papers in Herpetology

FLORIDA: ST. LUCIE County: Fort Pierce, 2100 Elizabeth Avenue (27.40840oN, 80 .34595OW). May 11, 2009. Ken Hibbard. Verified by Kenneth L. Krysko. Florida Museum of Natural History, University of Florida. UF 155444. First county record. One adult female; heavily infested with ectoparasitic pterygosomatid mites, collected from a porch screen of a residence at 2200 h. Three other Hemidactylus mabouia were observed at this same locality at 2000 h on May 13, 2009; they are common in sections of the Fort Pierce area. This invasive African species is currently the most widespread and rapidly spreading nonindigenous gecko in southern and central …


On The Monkeys Of The Amazon (1852), Alfred Russel Wallace Jan 2009

On The Monkeys Of The Amazon (1852), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.


On The Law Which Has Regulated The Introduction Of New Species (1855), Alfred Russel Wallace Jan 2009

On The Law Which Has Regulated The Introduction Of New Species (1855), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.


On The Tendency Of Varieties To Depart Indefinitely From The Original Type (1858), Alfred Russel Wallace Jan 2009

On The Tendency Of Varieties To Depart Indefinitely From The Original Type (1858), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.


Demographics, Activity, And Habitat Selection Of The Eastern Box Turtle (Terrapene C. Carolina) In West Virginia, Justin Adam Weiss Jan 2009

Demographics, Activity, And Habitat Selection Of The Eastern Box Turtle (Terrapene C. Carolina) In West Virginia, Justin Adam Weiss

Theses, Dissertations and Capstones

Little is known about the eastern box turtle, Terrapene c. carolina, in West Virginia. The purpose of this study was to compare demographic data between two populations of box turtles, to determine which environmental parameter(s) influence activity patterns, and to describe the optimal habitat of the box turtles at two study sites (Lake and State Park) at Beech Fork Wildlife Management Area. I observed male-skewed sex ratios and low numbers of juveniles in both populations. Male turtles were larger than females in carapace length, but females were larger in carapace height. Turtles at the Lake site exhibited greater body mass …


Post Weaning Management Of Heifer Calves Impacts Average Daily Gain And Feed Efficiency As Pregnant Heifers, D. M. Larson, Tonya L. Meyer, L. A. Stalker, Richard N. Funston Jan 2009

Post Weaning Management Of Heifer Calves Impacts Average Daily Gain And Feed Efficiency As Pregnant Heifers, D. M. Larson, Tonya L. Meyer, L. A. Stalker, Richard N. Funston

West Central Research and Extension Center, North Platte

Three experiments evaluated replacement heifer development systems and subsequent effects on gain and efficiency of pregnant heifers. In Exp. 1 and 2, were developed grazing corn residue (CR; 422 ± 5 kg) or fed in a dry lot (DL; 446 ± 5 kg) prior to breeding. In Exp. 1, a subset of pregnant heifers (n = 40) were individually fed a diet composed of 90% grass hay (11.7 % CP; DM basis) and 10% of a wet distillers grains plus solubles/straw mixture (21.8 % CP; DM basis) during late gestation. In Exp. 2, 55 pregnant …


Characterization Of 24 Microsatellite Loci In Delta Smelt, Hypomesus Transpacificus, And Their Cross-Species Amplification In Two Other Smelt Species Of The Osmeridae Family, Kathleen M. Fisch, Jessica Lynn Petersen, Melinda R. Baerwald, John K. Pedroia, Bernie May Jan 2009

Characterization Of 24 Microsatellite Loci In Delta Smelt, Hypomesus Transpacificus, And Their Cross-Species Amplification In Two Other Smelt Species Of The Osmeridae Family, Kathleen M. Fisch, Jessica Lynn Petersen, Melinda R. Baerwald, John K. Pedroia, Bernie May

Department of Animal Science: Faculty Publications

We characterized 24 polymorphic tetranucleotide microsatellite loci for delta smelt (Hypomesus transpacificus) endemic to the San Francisco Bay Estuary, California, USA. Screening of samples (n = 30) yielded two to 26 alleles per locus with observed levels of heterozygosity ranging from 0.17 to 1.0. Only one locus deviated from Hardy–Weinberg equilibrium, suggesting these individuals originate from a single panmictic population. Linkage disequilibrium was found in two pairs of loci after excluding the locus out of Hardy–Weinberg equilibrium. Twenty-two primer pairs cross-amplified in wakasagi smelt (Hypomesus nipponensis), and 15 primer pairs cross-amplified in longfin smelt ( …


Basking Behavior Of Emydid Turtles (Chysemys Picta Marginata, Graptemys Geographica, And Trachemys Scripta Elegans) In An Urban Landscape, W. E. Peterman, Travis J. Ryan Jan 2009

Basking Behavior Of Emydid Turtles (Chysemys Picta Marginata, Graptemys Geographica, And Trachemys Scripta Elegans) In An Urban Landscape, W. E. Peterman, Travis J. Ryan

Scholarship and Professional Work - LAS

Basking is common in emydid turtles and is generally accepted to be in thermoregulatory behavior. In 2004, we quantified and described the basking behavior of turtles in the Central Canal of Indianapolis. This canal system runs through an urban landscape that is dominated by fragmented woodlots, residential areas. and commercial areas. We observed that basking turtles exhibited variable basking behavior. with spatial and temporal shins in basking behavior from east-facing banks in the morning to west-facing banks in the afternoon. Turtles in the Central Canal are subject to frequent disturbance, which altered basking behavior. Many turtles forewent aerial basking on …


Assessment Of River Herring And Striped Bass In The Connecticut River: Abundance, Population Structure, And Predator/Prey Interactions, Justin P. Davis, Eric T. Schultz, Jason Vokoun Jan 2009

Assessment Of River Herring And Striped Bass In The Connecticut River: Abundance, Population Structure, And Predator/Prey Interactions, Justin P. Davis, Eric T. Schultz, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring A. aestivalis, collectively referred to as river herring, have declined in the Connecticut River. An explanatory hypothesis for these declines is that predation pressures have increased as a result of recent increases in abundance of sympatric striped bass Morone saxatilis. We sampled river herring and striped bass from the stretch of the Connecticut River between Wethersfield, CT and Holyoke, MA during the vernal migration seasons of 2005-2008. The objectives of the sampling program were to assess abundance, temporal/spatial distribution, and population structure of both river herring and striped bass, …


Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun Jan 2009

Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring Alosa aestivalis, collectively referred to as river herring, have declined in the Connecticut River. A hypothesis for why river herring have declined is that predation pressures have increased associated with recent increases in abundance of striped bass Morone saxatilis. Information on striped bass abundance, size structure, and consumption rates are required to test this hypothesis. This study was designed to provide estimates of striped bass population size in the Connecticut River during the spring migration season, via an intensive mark-recapture exercise and either an open or robust mark-recapture model. …


The Prairie Naturalist Manuscript Submission Guidelines, Christopher N. Jacques, Troy W. Grovenburg, Jonathan Jenks Jan 2009

The Prairie Naturalist Manuscript Submission Guidelines, Christopher N. Jacques, Troy W. Grovenburg, Jonathan Jenks

The Prairie Naturalist

These guidelines present The Prairie Naturalist (PNAT) policies and procedures for submitting scientific manuscripts for consideration for publication. In January 2009, a change in Editorial staff occurred and these guidelines address the ongoing transition and update the online "Suggestions for Contributors" guidelines provided on the PNAT website (http://www.fhsu.edu/biology/pn/prairienat.htm); these instructions supersede all previous guidelines. Tables and appendices are included for common word expressions with superfluous wording, examples of correct format and style guidelines for tables accompanying manuscripts, guidance in properly preparing Research Articles and Notes, citing literature, and mandatory abbreviations for tables, figures and parenthetical expressions.


Thirty-Seven Additional Microsatellite Loci In The Pacific Lion-Paw Scallop (Nodipecten Subnodosus) And Cross-Amplification In Other Pectinids, Jessica Lynn Petersen, Ana M. Ibarra, Bernie May Jan 2009

Thirty-Seven Additional Microsatellite Loci In The Pacific Lion-Paw Scallop (Nodipecten Subnodosus) And Cross-Amplification In Other Pectinids, Jessica Lynn Petersen, Ana M. Ibarra, Bernie May

Department of Animal Science: Faculty Publications

We characterized 37 new microsatellite markers in the Pacific lion-paw scallop (Nodipecten subnodosus) and tested for cross-amplification in four other species. Genetic diversity was estimated using 24 individuals from the Lagoon Ojo de Liebre, B.C.S., Mexico. Allelic richness varied from 5 to 27 alleles per locus and the average expected heterozygosity was 0.76. Ten loci exhibited significant departure from Hardy–Weinberg equilibrium likely due to the presence of null alleles. Sixteen of these markers cross-amplified in closely related N. nodosus, while little or no amplification was observed in three Argopecten species.


Courtship Effort Is A Better Predictor Of Mating Success Than Ornamentation For Male Wolf Spiders, Paul S. Shamble, Dustin J. Wilgers, Katharine A. Swoboda, Eileen Hebets Jan 2009

Courtship Effort Is A Better Predictor Of Mating Success Than Ornamentation For Male Wolf Spiders, Paul S. Shamble, Dustin J. Wilgers, Katharine A. Swoboda, Eileen Hebets

Eileen Hebets Publications

Female mate choice decisions are often based on a variety of male characteristics, some of which may reflect male quality via condition-dependent trait expression. Here, we explore the condition dependence of a male secondary sexual trait in a wolf spider and examine its influence on female mate choice. In the wolf spider Schizocosa uetzi, mature males possess a multimodal courtship display (visual + seismic) in which they slowly raise and lower their dark colored forelegs. Foreleg color is highly variable among S. uetzi males with respect to both total amount and darkness. Using diet manipulations in conjunction with color …


Qualitative Freshwater Mussel Survey Of The South Fork Spring River, Missouri And Arkansas, H. C. Martin, John L. Harris, Alan D. Christian Jan 2009

Qualitative Freshwater Mussel Survey Of The South Fork Spring River, Missouri And Arkansas, H. C. Martin, John L. Harris, Alan D. Christian

Journal of the Arkansas Academy of Science

A qualitative freshwater mussel survey was performed in the South Fork Spring River, Arkansas between May 13 and June 20, 2006 to assess community composition, density, and the presence of endangered mussel species (Family Unionidae). Twenty-one species from 460 individuals of mussels were collected using qualitative methods. Of those 21 species, 11 were ranked as S1, S2, or S3 using rankings established by the Arkansas Natural Heritage Commission Heritage Program. Three species, Amblema plicata (Say 1817), Lampsilis reeveiana (Call 1887), and Ptychobranchus occidentalis (Conrad 1836), comprised 48% of all mussels collected with 12%, 15%, and 21%, respectively. Mussel abundance within …


Species Richness, Distribution, And Relative Abundance Of Freshwater Mussels (Bivalvia: Unionidae) Of The Buffalo National River, Arkansas, M. Matthews, F. Usrey, S. W. Hodges, John L. Harris, Alan D. Christian Jan 2009

Species Richness, Distribution, And Relative Abundance Of Freshwater Mussels (Bivalvia: Unionidae) Of The Buffalo National River, Arkansas, M. Matthews, F. Usrey, S. W. Hodges, John L. Harris, Alan D. Christian

Journal of the Arkansas Academy of Science

The Buffalo River in north-central Arkansas is approximately 246 km long and flows through the Boston Mountains and Springfield and Salem Plateaus to the White River near Buffalo City. The Buffalo River is America’s first National River with the National Park Service owning 11% of land in the watershed. The objectives of this project were to survey the entire perennially wet length of river, search for mussels of conservation concern, and document the freshwater mussel assemblages. During 2004 and 2005, 235 km of the river were qualitatively and quantitatively surveyed. We documented 64 mussel assemblages. Time constrained qualitatively sampled assemblages …


Determination Of Benthic Soil Conditions Using Nematodes: Nematode Foodweb Conditions Of Fish Ponds In The Lincoln And Desha Counties Of Arkansas, M. M. Matute, P. W. Perschbacher, A. Newell Jan 2009

Determination Of Benthic Soil Conditions Using Nematodes: Nematode Foodweb Conditions Of Fish Ponds In The Lincoln And Desha Counties Of Arkansas, M. M. Matute, P. W. Perschbacher, A. Newell

Journal of the Arkansas Academy of Science

We determined the health status of similar channel catfish (Ictalurus punctatus) ponds in Lincoln and Desha counties of Arkansas, using the nematode soil food web condition as our reference point. Soil nematodes were categorized into colonizer-persister (cp) groups, based on their life course characteristics e.g sensitivity to environmental changes, body size, etc. These cp groups represent different components of the soil food web, which in turn were indicators of soil conditions. Benthic soil samples were collected at four week intervals over a 4-month period, from 6-ponds in each county. The nematodes were extracted according to standard methods and the recovered …


Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger Jan 2009

Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger

College of Graduate Studies: Theses & Dissertations

Author's Abstract: Skrjabinoptera phrynosoma (Ortlepp) Schulz, 1927 is a common parasitic nematode of horned lizards. The life cycle of S. phrynosoma was described by Lee in 1957, but has received little attention since. The present study addressed effect of season as well as host characteristics on the infection dynamics in lizard hosts. In the Alvord Basin in southeastern Oregon, S. phrynosoma were collected from Phrynosoma platyrhinos Gerard 1852 horned lizards via stomach flushes, cloaca flushes and fecal pellet collections. Parasite load variables (number of nematodes per host, length of those nematodes, and total worm burden (ΣL)) were analyzed within three …


A Plesiosaur Containing An Ichthyosaur Embryo As Stomach Contents From The Sundance Formation Of The Bighorn Basin, Wyoming, F. Robin O’Keefe, Hallie P. Street, Jean Pierre Cavigelli, John J. Socha, R. Dennis O'Keefe Jan 2009

A Plesiosaur Containing An Ichthyosaur Embryo As Stomach Contents From The Sundance Formation Of The Bighorn Basin, Wyoming, F. Robin O’Keefe, Hallie P. Street, Jean Pierre Cavigelli, John J. Socha, R. Dennis O'Keefe

Biological Sciences Faculty Research

Herein we report the discovery of an ichthyosaur embryo from the Upper Member of the Sundance Formation (Oxfordian) of the Bighorn Basin, Wyoming. The specimen is the first known ichthyosaur embryo from the Upper Jurassic, and is the first Jurassic ichthyosaur embryo from North America. The embryo was discovered in close association with the abdomen of an articulated partial plesiosaur skeleton, and several lines of evidence support the interpretation of the embryo as plesiosaur stomach contents. The small size and extremely poor ossification of the embryo indicate that the animal was probably not a neonate. Although the taxonomic affinities of …


Osteology Of The Cryptocleidoid Plesiosaur Tatenectes Laramiensis, With Comments On The Taxonomic Status Of The Cimoliasauridae, F. Robin O’Keefe, Hallie P. Street Jan 2009

Osteology Of The Cryptocleidoid Plesiosaur Tatenectes Laramiensis, With Comments On The Taxonomic Status Of The Cimoliasauridae, F. Robin O’Keefe, Hallie P. Street

Biological Sciences Faculty Research

Recent field work in the Bighorn Basin, Wyoming has recovered significant new material of the plesiosaur Tatenectes laramiensis. The majority of cryptocleidoid plesiosaurs have been recovered from Middle and Upper Jurassic units (Oxford and Kimmeridge Clays, respectively) in the United Kingdom, but Tatenectes laramiensis is one of at least two cryptocleidoids known from the Upper Sundance Member of the Sundance Formation (Oxfordian) of North America. Although poorly known, they bear directly on both the phylogeny and biogeography of the cryptocleidoid plesiosaurs. Here we describe new fossil material of Tatenectes, and reevaluate the phylogenetic position of this genus based on all …