Life Sciences Commons^™

The Burden Of Motherhood: The Effect Of Reproductive Load On Female Lizard Locomotor, Foraging, And Social Behavior, Michele A. Johnson, J. L. Caton, R. E. Cohen, J. R. Vandecar, J. Wade

Biology Faculty Research

The costs of reproduction, involving demands associated with both current and future reproductive efforts, may place a substantial burden on females. However, animals may minimize these costs by modifying their behavior across the reproductive cycle. We examined the effects of reproductive load on three types of behavior (locomotion, foraging, and social displays) in green anole lizards (Anolis carolinensis) by comparing egg, follicle, and oviduct mass and volume with field observational data. We found that female locomotor and social display behaviors decreased as reproductive load increased, suggesting behavioral modification in these traits, but we detected no relationship between foraging and …

Historical Biogeography Of Velvet Ants (Hymenoptera: Mutillidae) In The North American Deserts And Arid Lands, Joseph S. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries, scientists have been intrigued by the high amount of biodiversity that is found in the deserts of North America. Recently, several studies have investigated the causes of the high diversity found in desert-dwelling mammals, reptiles, and amphibians. These studies have found that many of these organisms seem to have diversified in response to the same historical events. Little work has been done, however, on diverse desert-dwelling insect groups. In this dissertation, I investigate the patterns of genetic diversity in four groups of nocturnal wasps called velvet ants. I compare the patterns of genetic diversity to the historical events …

Role Of Eukaryotic Sel-1 Like Repeat Containing Genes In Helicobacter Pylori Evolution And Pathogenesis., Kalyani Putty

Electronic Theses and Dissertations

Background: Helicobacter pylori (Hp) establishes life-long gastric infection in billions of humans, and is often responsible for diseases such as peptic ulcer and gastric cancer. Cumulative actions of genetic drift and natural selection over several millennia sculpted the present Hp population structure, which is characterized by extreme genetic diversity and striking geographic clustering of genotypes. Natural selection is more commonly imprinted in DNA sequences of Hp proteins that interact with host components; however, in most instances biological relevance of selection during Hp infection remains unknown. Here, I attempted to elucidate the consequence of natural selection in two different contexts: (1) …

Structure And Reactivity Of Hexacoordinate Hemoglobins, Smita Kakar, Federico G. Hoffmann, Jay F. Storz, Marian Fabian, Mark S. Hargrove

Jay F. Storz Publications

The heme prosthetic group in hemoglobins is most often attached to the globin through coordination of either one or two histidine side chains. Those proteins with one histidine coordinating the heme iron are called “pentacoordinate” hemoglobins, a group represented by red blood cell hemoglobin and most other oxygen transporters. Those with two histidines are called “hexacoordinate hemoglobins”, which have broad representation among eukaryotes. Coordination of the second histidine in hexacoordinate Hbs is reversible, allowing for binding of exogenous ligands like oxygen, carbon monoxide, and nitric oxide. Research over the past several years has produced a fairly detailed picture of the …

Retention And Loss Of Rna Interference Pathways In Trypanosomatid Protozoans, Lon-Fye Lye, Katherine Owens, Huafang Shi, Silvane M. F. Murta, Ana Carolina Vieira, Salvatore J. Turco, Christian Tschudi, Elisabetta Ullu, Stephen M. Beverley

Molecular and Cellular Biochemistry Faculty Publications

RNA interference (RNAi) pathways are widespread in metaozoans but the genes required show variable occurrence or activity in eukaryotic microbes, including many pathogens. While some Leishmania lack RNAi activity and Argonaute or Dicer genes, we show that Leishmania braziliensis and other species within the Leishmania subgenus Viannia elaborate active RNAi machinery. Strong attenuation of expression from a variety of reporter and endogenous genes was seen. As expected, RNAi knockdowns of the sole Argonaute gene implicated this protein in RNAi. The potential for functional genetics was established by testing RNAi knockdown lines lacking the paraflagellar rod, a key component of the …

The Combined Effect Of Environmental And Host Factors On The Emergence Of Viral Rna Recombinants, Hannah M. Jaag, Peter D. Nagy

Plant Pathology Faculty Publications

Viruses are masters of evolution due to high frequency mutations and genetic recombination. In spite of the significance of viral RNA recombination that promotes the emergence of drug-resistant virus strains, the role of host and environmental factors in RNA recombination is poorly understood. Here we report that the host Met22p/Hal2p bisphosphate-3'-nucleotidase regulates the frequency of viral RNA recombination and the efficiency of viral replication. Based on Tomato bushy stunt virus (TBSV) and yeast as a model host, we demonstrate that deletion of MET22 in yeast or knockdown of AHL, SAL1 and FRY1 nucleotidases/phosphatases in plants leads to increased TBSV recombination …

The Mir-15/107 Group Of Microrna Genes: Evolutionary Biology, Cellular Functions, And Roles In Human Diseases, John R. Finnerty, Wang-Xia Wang, Sébastien S. Hébert, Bernard R. Wilfred, Guogen Mao, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

The miR-15/107 group of microRNA (miRNA) gene is increasingly appreciated to serve key functions in humans. These miRNAs regulate gene expression involved in cell division, metabolism, stress response, and angiogenesis in vertebrate species. The miR-15/107 group has also been implicated in human cancers, cardiovascular disease and neurodegenerative disease, including Alzheimer's disease. Here we provide an overview of the following: (1) the evolution of miR-15/107 group member genes; (2) the expression levels of miRNAs in mammalian tissues; (3) evidence for overlapping gene-regulatory functions by different miRNAs; (4) the normal biochemical pathways regulated by miR-15/107 group miRNAs; and (5) the roles played …

New Views On Strand Asymmetry In Insect Mitochondrial Genomes, Shu-Jun Wei, Min Shi, Xue-Xin Chen, Michael J. Sharkey, Cornelis Van Achterberg, Gong-Yin Ye, Jun-Hua He

Entomology Faculty Publications

Strand asymmetry in nucleotide composition is a remarkable feature of animal mitochondrial genomes. Understanding the mutation processes that shape strand asymmetry is essential for comprehensive knowledge of genome evolution, demographical population history and accurate phylogenetic inference. Previous studies found that the relative contributions of different substitution types to strand asymmetry are associated with replication alone or both replication and transcription. However, the relative contributions of replication and transcription to strand asymmetry remain unclear. Here we conducted a broad survey of strand asymmetry across 120 insect mitochondrial genomes, with special reference to the correlation between the signs of skew values and …

Access To Mutualistic Endosymbiotic Microbes: An Underappreciated Benefit Of Group Living, Michael Lombardo

Michael P Lombardo

"The original publication is available at www.springerlink.com"

A central question in behavioral ecology has been why animals live in groups. Previous theories about the evolution of sociality focused on the potential benefits of decreased risk of predation, increased foraging or feeding efficiency, and mutual aid in defending resources and/or rearing offspring. This paper argues that access to mutualistic endosymbiotic microbes is an underappreciated benefit of group living and sets out to reinvigorate Troyer’s hypothesis that the need to obtain cellulolytic microbes from conspecifics influenced the evolution of social behavior in herbivores and to extend it to nonherbivores. This extension is …

On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo

Michael P Lombardo

"The definitive version is available at www.blackwell-synergy.com".

Sexually transmitted diseases (STDs) in animals are caused by pathogens that are transmitted during copulation. Birds have played an important role in the development of STD-centered theories of mating behavior. However, it is not known whether STDs exist in wild bird populations. While the avian cloaca with its dual functions of gamete transfer and excretion seemingly predisposes birds for the evolution of STDs, the life history patterns of most birds (i.e., seasonal breeders with relatively brief annual periods of sexual activity) suggest otherwise. The importance of STDs as selective forces that shape host …

Comparative Mitogenomics Of Braconidae (Insecta: Hymenoptera) And The Phylogenetic Utility Of Mitochondrial Genomes With Special Reference To Holometabolous Insects, Shu-Jun Wei, Min Shi, Michael J. Sharkey, Cornelis Van Achterberg, Xue-Xin Chen

Entomology Faculty Publications

BACKGROUND: Animal mitochondrial genomes are potential models for molecular evolution and markers for phylogenetic and population studies. Previous research has shown interesting features in hymenopteran mitochondrial genomes. Here, we conducted a comparative study of mitochondrial genomes of the family Braconidae, one of the largest families of Hymenoptera, and assessed the utility of mitochondrial genomic data for phylogenetic inference at three different hierarchical levels, i.e., Braconidae, Hymenoptera, and Holometabola.

RESULTS: Seven mitochondrial genomes from seven subfamilies of Braconidae were sequenced. Three of the four sequenced A+T-rich regions are shown to be inverted. Furthermore, all species showed reversal of strand asymmetry, suggesting …

Gc-Biased Evolution Near Human Accelerated Regions, Sol Katzman, Andrew D. Kern, Katherine S. Pollard, Sofie R. Salama, David Haussler

Dartmouth Scholarship

Regions of the genome that have been the target of positive selection specifically along the human lineage are of special importance in human biology. We used high throughput sequencing combined with methods to enrich human genomic samples for particular targets to obtain the sequence of 22 chromosomal samples at high depth in 40 kb neighborhoods of 49 previously identified 100–400 bp elements that show evidence for human accelerated evolution. In addition to selection, the pattern of nucleotide substitutions in several of these elements suggested an historical bias favoring the conversion of weak (A or T) alleles into strong (G or …

The Complexity And Origins Of The Human Eye: A Brief Study On The Anatomy, Physiology, And Origin Of The Eye, Evan T. Sebastian

Senior Honors Theses

The human eye has been the cause of much controversy in regards to its complexity and how the human eye came to be. Through following and discussing the anatomical and physiological functions of the eye, a better understanding of the argument of origins can be seen. The anatomy of the human eye and its many functions are clearly seen, through its complexity. When observing the intricacy of vision and all of the different aspects and connections, it does seem that the human eye is a miracle, no matter its origins. Major biological functions and processes occurring in the retina show …

Robert Koch, Creation, And The Specificity Of Germs, Alan L. Gillen, Douglas Oliver, Frank Sherwin

Faculty Publications and Presentations

Microbiology is dominated by evolution today. Just look at any text, journal article, or the topics presented at professional scientific meetings. Darwin is dominant.

Microbiology is dominated by evolution today. Just look at any text, journal article, or the topics presented at professional scientific meetings. Darwin is dominant. Many argue that “nothing in biology makes sense except in the light of evolution” (Dobzhansky 1973). But it was not always this way. In fact, a review of the major founders of microbiology has shown that they were creationists.1 We would argue that a better idea thanevolution and one of much …

Distinct Evolutionary Histories Of The Dna-A And Dna-B Components Of Bipartite Begomoviruses, Rob W. Briddon, Basavaprabhu L. Patil, Basavaraj Bagewadi, Muhammad Shah Nawaz-Ul-Rehman, Claude M. Fauquet

Plant Pathology Faculty Publications

BACKGROUND: Viruses of the genus Begomovirus (family Geminiviridae) have genomes consisting of either one or two genomic components. The component of bipartite begomoviruses known as DNA-A is homologous to the genomes of all geminiviruses and encodes proteins required for replication, control of gene expression, overcoming host defenses, encapsidation and insect transmission. The second component, referred to as DNA-B, encodes two proteins with functions in intra- and intercellular movement in host plants. The origin of the DNA-B component remains unclear. The study described here was initiated to investigate the relationship between the DNA-A and DNA-B components of bipartite begomoviruses with a …

Purification And Characterization Of Cytoplasmic Nadp+- Isocitrate Dehydrogenase, And Amplification Of The Nadp+-Idh Gene From The Wing-Dimorphic Sand Field Cricket, Gryllus Firmus, Anthony J. Zera, Susan Newman, David Berkheim, Christine Black, Lindsay Klug, Erica Crone

School of Biological Sciences: Faculty Publications

Cytoplasmic NADP+-isocitrate dehydrogenase (NADP+-IDH) has been purified and characterized, and its gene sequenced in many animal, plant, and yeast species. However, much less information is available on this enzyme-gene in insects. As a first step in investigating the biochemical and molecular mechanisms by which NADP+-IDH contributes to adaptations for flight vs. reproduction in insects, the enzyme was purified to homogeneity in the wing-dimorphic cricket, Gryllus firmus, characterized, and its corresponding gene sequenced. Using a combination of polyethylene glycol precipitation, Cibacron-Blue affinity chromatography, and hydrophobic interaction chromatography the enzyme was purified 291-fold (7% yield; specific activity = 15.8 μmol NADPH/min/mg …

Alfred Russel Wallace, Geographer, Charles H. Smith

DLPS Faculty Publications

Among the great explorers and thinkers who advanced geography in the nineteenth century and helped it evolve into the subject that exists today is a man who is not always connected with the field, Alfred Russel Wallace (1823–1913). Most commonly recognized as ‘the other man’ in the history of the discovery of the principle of natural selection, Wallace’s commitment to the study of landscape and its physical, biological, and human elements was lifelong, and resulted in a wide range of contributions to biogeography, physical geography, human geography, and ethnography. In this year of the double anniversaries of Charles Darwin’s birth …

Cognitive Representation In Transitive Inference: A Comparison Of Four Corvid Species, Alan B. Bond, Cynthia A. Wei, Alan C. Kamil

Alan Bond Publications

During operant transitive inference experiments, subjects are trained on adjacent stimulus pairs in an implicit linear hierarchy in which responses to higher ranked stimuli are rewarded. Two contrasting forms of cognitive representation are often used to explain resulting choice behavior. Associative representation is based on memory for the reward history of each stimulus. Relational representation depends on memory for the context in which stimuli have been presented. Natural history characteristics that require accurate configural memory, such as social complexity or reliance on cached food, should tend to promote greater use of relational representation. To test this hypothesis, four corvid species …

The Origin Of Human Races And The Antiquity Of Man Deduced From The Theory Of “Natural Selection” (1864), Alfred Russel Wallace

Alfred Russel Wallace Classic Writings

No abstract provided.

Investigating Instructors' Conceptions Of Evolution Through The Development Of The Classroom Test Of Evolutionary Reasoning, Patricia Eileen Palko

Electronic Theses and Dissertations

In order to assess the evolutionary understanding of high school biology teachers, an instrument entitled the Classroom Test of Evolutionary Reasoning (CTER) was developed. Content, response process, relations to another variable (the Conceptual Inventory of Natural Selection, or CINS), and internal structure evidence were compiled. The second version of the CTER was found to have adequate reliability and validity estimates to allow it to continue to be used as a measurement tool for an understanding of evolution. When assessing a sample of teachers (n = 724), the mean score was 6.35 out of a possible 13 points. The sample was …

Introduction: Protistan Biology, Horizontal Gene Transfer, And Common Descent Uncover Faulty Logic In Intelligent Design, Avelina Espinosa

Arts & Sciences Faculty Publications

THE International Society of Protistologists (ISOP) organized a pre-meeting workshop entitled ‘‘Horizontal Gene Transfer and Phylogenetic Evolution Debunk Intelligent Design,’’ as part of the 1st North American Section meeting held June 11–13, 2009, at Roger Williams University, Bristol, RI, USA. This workshop focused on the acceptance of Darwinian evolution in the United States and the role of intelligent design (ID) in the ongoing controversy between scientific knowledge and popular belief. Intelligent design, a doctrine born in the 1980s, proposes that a ‘‘Designer’’ is responsible for the complexity in biological systems and that Darwinism cannot explain holistically the origin and evolution …

Biogeography And Diversification In The Neotropics: Testing Macroevolutionary Hypotheses Using Molecular Phylogenetic Data, Juan Manuel Daza Rojas

Electronic Theses and Dissertations

Lineage diversification in the Neotropics is an interesting topic in evolutionary biology and one of the least understood. The complexity of the region precludes generalizations regarding the historical and evolutionary processes responsible for the observed high diversity. Here, I use molecular data to infer evolutionary relationships and test hypotheses of current taxonomy, species boundaries, speciation and biogeographic history in several lineages of Neotropical snakes. I comprehensively sampled a widely distributed Neotropical colubrid snake and Middle American pitvipers and combined my data with published sequences. Within the colubrid genus Leptodeira, mitochondrial and nuclear markers revealed a phylogeograhic structure that disagrees with …

Adaptive Evolution And Inherent Tolerance To Extreme Thermal Environments, Jennifer Cox, Alyxandria Schubert, Michael Travisano, Catherine Putonti

Bioinformatics Faculty Publications

Background

When introduced to novel environments, the ability for a species to survive and rapidly proliferate corresponds with its adaptive potential. Of the many factors that can yield an environment inhospitable to foreign species, phenotypic response to variation in the thermal climate has been observed within a wide variety of species. Experimental evolution studies using bacteriophage model systems have been able to elucidate mutations, which may correspond with the ability of phage to survive modest increases/decreases in the temperature of their environment.

Results

Phage ΦX174 was subjected to both elevated (50°C) and extreme (70°C+) temperatures for anywhere from a few …

Comparing Models Of Evolution For Ordered And Disordered Proteins, Celeste J. Brown, Audra K. Johnson, Gary W. Daughdrill

Molecular Biosciences Faculty Publications

Most models of protein evolution are based upon proteins that form relatively rigid 3D structures. A significant fraction of proteins, the so-called disordered proteins, do not form rigid 3D structures and sample a broad conformational ensemble. Disordered proteins do not typically maintain long-range interactions, so the constraints on their evolution should be different than ordered proteins. To test this hypothesis, we developed and compared models of evolution for disordered and ordered proteins. Substitution matrices were constructed using the sequences of putative homologs for sets of experimentally characterized disordered and ordered proteins. Separate matrices, at three levels of sequence similarity ( …

Copy Number Variation Shapes Genome Diversity In Arabidopsis Over Immediate Family Generational Scales, Seth Debolt

Horticulture Faculty Publications

Arabidopsis thaliana is the model plant and is grown worldwide by plant biologists seeking to dissect the molecular underpinning of plant growth and development. Gene copy number variation (CNV) is a common form of genome natural diversity that is currently poorly studied in plants and may have broad implications for model organism research, evolutionary biology, and crop science. Herein, comparative genomic hybridization (CGH) was used to identify and interrogate regions of gene CNV across the A. thaliana genome. A common temperature condition used for growth of A. thaliana in our laboratory and many around the globe is 22 degrees C. …

Microevolution Of Intermediary Metabolism: Evolutionary Genetics Meets Metabolic Biochemistry, Anthony J. Zera

School of Biological Sciences: Faculty Publications

During the past decade, microevolution of intermediary metabolism has become an important new research focus at the interface between metabolic biochemistry and evolutionary genetics. Increasing recognition of the importance of integrative studies in evolutionary analysis, the rising interest in ‘evolutionary systems biology’, and the development of various ‘omics’ technologies have all contributed significantly to this developing interface. The present review primarily focuses on five prominent areas of recent research on pathway microevolution: lipid metabolism and life-history evolution; the electron transport system, hybrid breakdown and speciation; glycolysis, alcohol metabolism and population adaptation in Drosophila; chemostat selection in microorganisms; and anthocyanin …

Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan

Biological Sciences Faculty Publications

The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size …