Evolution Commons^™

The Origin And Molecular Evolution Of Two Multigene Families: G-Protein Coupled Receptors And Glycoside Hydrolase Families, Seong-Il Eyun

School of Biological Sciences: Dissertations, Theses, and Student Research

Multigene family is a group of genes that arose from a common ancestor by gene duplication. Gene duplications are a major driving force of new function acquisition. Multigene family thus has a fundamental role in adaptation. To elucidate their molecular evolutionary mechanisms, I chose two multigene families: chemosensory receptors and glycoside hydrolases. I have identified complete repertoires of trace amine-associated receptors (TAARs), a member of chemosensory receptors, from 38 metazoan genomes. An ancestral-type TAAR emerged before the divergence between gnathostomes (jawed vertebrates) and sea lamprey (jawless fish). Primary amine detecting TAARs (TAAR1-4) are found to be older and have evolved …

The Rate And Effects Of Spontaneous Mutation On Fitness Traits In The Social Amoeba, Dictyostelium Discoideum, David W. Hall, Sara Fox, Jennie J. Kuzdzal-Fick, Joan E. Strassmann, David C. Queller

Biology Faculty Research

We performed a mutation accumulation (MA) experiment in the social amoeba Dictyostelium discoideum to estimate the rate and distribution of effects of spontaneous mutations affecting eight putative fitness traits. We found that the per-generation mutation rate for most fitness components is 0.0019 mutations per haploid genome per generation or larger. This rate is an order of magnitude higher than estimates for fitness components in the unicellular eukaryote Saccharomyces cerevisiae, even though the base-pair substitution rate is two orders of magnitude lower. The high rate of fitness-altering mutations observed in this species may be partially explained by a large mutational target …

Comparative Approaches To Studying Strategy: Towards An Evolutionary Account Of Primate Decision Making, Sarah F. Brosnan, Michael J. Beran, Audrey E. Parrish, Sara A. Price, Bart J. Wilson

Economics Faculty Articles and Research

How do primates, humans included, deal with novel problems that arise in interactions with other group members? Despite much research regarding how animals and humans solve social problems, few studies have utilized comparable procedures, outcomes, or measures across different species. Thus, it is difficult to piece together the evolution of decision making, including the roots from which human economic decision making emerged. Recently, a comparative body of decision making research has emerged, relying largely on the methodology of experimental economics in order to address these questions in a cross-species fashion. Experimental economics is an ideal method of inquiry for this …

Animals Represent The Past And The Future, Thomas R. Zentall

Psychology Faculty Publications

It has been proposed by some that only humans have the ability to mentallytravel back in time (i.e., have episodic memory) and forward in time (i.e., have the ability to simulate the future). However, there is evidence from a variety of nonhuman animals (e.g., primates, dolphins, scrub jays, rats, and pigeons) that they have some ability to recover personal memories of what-where-when an event occurred (an earlier requirement of the ability to recover an episodic memory) and answer unexpected questions (another requirement to distinguish between semantic and episodic memory). Also, perhaps more critically, according to Tulving’s more recent definition of …

Evolution Of A Higher Intracellular Oxidizing Environment In Caenorhabditis Elegans Under Relaxed Selection, Joanna Joyner-Matos, Kiley A. Hicks, Dustin Cousins, Michelle Keller, Dee R. Denver, Charles F. Baer, Suzanne Estes

Biology Faculty Publications and Presentations

We explored the relationship between relaxed selection, oxidative stress, and spontaneous mutation in a set of mutationaccumulation (MA) lines of the nematode Caenorhabditis elegans and in their common ancestor. We measured steady-state levels of free radicals and oxidatively damaged guanosine nucleosides in the somatic tissues of five MA lines for which nuclear genome base substitution and GC-TA transversion frequencies are known. The two markers of oxidative stress are highly correlated and are elevated in the MA lines relative to the ancestor; point estimates of the per-generation rate of mutational decay (DM) of these measures of oxidative stress are similar to …

Wallace On Natural Selection: What Did He Really Have In Mind?, Charles H. Smith

DLPS Faculty Publications

No abstract provided.

Surprisingly Little Population Genetic Structure In A Fungus-Associated Beetle Despite Its Exploitation Of Multiple Hosts, Corlett W. Wood , '08, H. M. Donald, Vincent A. Formica, E. D. Brodie Iii

Biology Faculty Works

In heterogeneous environments, landscape features directly affect the structure of genetic variation among populations by functioning as barriers to gene flow. Resource-associated population genetic structure, in which populations that use different resources (e.g., host plants) are genetically distinct, is a well-studied example of how environmental heterogeneity structures populations. However, the pattern that emerges in a given landscape should depend on its particular combination of resources. If resources constitute barriers to gene flow, population differentiation should be lowest in homogeneous landscapes, and highest where resources exist in equal proportions. In this study, we tested whether host community diversity affects population genetic …

Fitness: Philosophical Problems, Grant Ramsey, Charles H. Pence

Faculty Publications

Fitness plays many roles throughout evolutionary theory, from a measure of populations in the wild to a central element in abstract theoretical presentations of natural selection. It has thus been the subject of an extensive philosophical literature, which has primarily centred on the way to understand the relationship between fitness values and reproductive outcomes. If fitness is a probabilistic or statistical quantity, how is it to be defined in general theoretical contexts? How can it be measured? Can a single conceptual model for fitness be offered that applies to all biological cases, or must fitness measures be case-specific? Philosophers have …

Purification And Characterization Of Oxidation-Resistant Ribonuclease Inhibitor Variants, Alec W. Uebersohn

Lawrence University Honors Projects

Ribonuclease inhibitor (RI) is an intracellular mammalian protein which binds vertebrate-specific ribonucleases; this interaction is one of the tightest non-covalent interactions yet discovered. The biological activity of RI is poorly understood, but it is thought to regulate the biological functions of ribonucleases, which include initiating blood vessel growth, maintaining neuron viability, attacking pathogens, and mediating cell stress responses. RI is also involved in pathways unrelated to ribonucleases, including interactions with Drosha and PTEN, an anti-tumor protein.

One of the defining characteristics of RI is its oxidation sensitivity, a result of its unusually high cysteine content. The oxidation of RI is …

Habitat And Host Indicate Lineage Identity In Colletotrichum Gloeosporioides S.L. From Wild And Agricultural Landscapes In North America, Vinson P. Doyle, Peter V. Oudemans, Stephen A. Rehner, Amy Litt

Publications and Research

Understanding the factors that drive the evolution of pathogenic fungi is central to revealing the mechanisms of virulence and host preference, as well as developing effective disease control measures. Prerequisite to these pursuits is the accurate delimitation of species boundaries. Colletotrichum gloeosporioides s.l. is a species complex of plant pathogens and endophytic fungi for which reliable species recognition has only recently become possible through a multi-locus phylogenetic approach. By adopting an intensive regional sampling strategy encompassing multiple hosts within and beyond agricultural zones associated with cranberry (Vaccinium macrocarpon Aiton), we have integrated North America strains of Colletotrichum gloeosporioides s.l. from …

From Gibbons To Gymnasts: A Look At The Biomechanics And Neurophysiology Of Brachiation In Gibbons And Its Human Rediscovery, Emma Et Pennock

Student Works

This conference paper serves to examine the evolutionary linkages of a brachiating ancestor in humans, the biomechanical and neurophysiology of modern day brachiators, and the human rediscovery of this form of locomotion. Brachiation is arguably one of the most metabolically effective modes of travel by any organism and can be observed most meritoriously in Gibbons. The purpose of the research conducted for this paper was to encourage further exploration of the neurophysiological similarities and differences between humans and non-human primates. The hope is that in spurring more interest and research in this area, further possibilities for rehabilitating brain injury will …

Predation And Behavioral Plasticity In Green Swordtails: Mate Choice In Females And Exploratory Behavior In Males, Andrew J. Melie

School of Biological Sciences: Dissertations, Theses, and Student Research

Two studies were carried out with green swordtails, Xiphophorus helleri, to investigate the effect of predation on swordtail behavior, and to determine how behavioral plasticity operates in both a mate choice and an anti-predator context. Male green swordtails vary in colorful conspicuous traits, e.g. the colorful dorsal fin and sword. Female swordtails have a preexisting bias for males with a sword, and prefer long-sworded males to short-sworded males, but this preference is plastic. The first study examined predator-related plasticity in the behavior of males differing in size. Smaller males showed greater behavioral plasticity; they were more active in the …

A Multi-Gene Molecular Systematic Study Of The Kickxellomycotina, Including The Examination Of Two New Genes (Mcm7 And Tsr1) For Phylogenetic Inference, Eric Dennis Tretter

Boise State University Theses and Dissertations

Kickxellomycotina is a recently described subphylum of Fungi defined by the presence of a unique disciform septal pore with a lenticular plug. The relationship between members of the group has proven difficult to resolve with traditional methods due to the degree of morphological and ecological variation among taxa within the clade. Furthermore, existing phylogenetic studies have lacked either the taxonomic coverage or had insufficient phylogenetic resolution to reveal the evolutionary history of the group.

In chapter one, I investigate the phylogenetic utility of two single-copy protein-coding genes, MCM7 and TSR1, to improve phylogenetic resolution within the clade. Suitable primers were …

The Effects Of Starvation Selection On Drosophila Melanogaster Life History And Development, Lauren A. Reynolds

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, animals may endure periods of famine to complete their life cycles. Starvation stress will increase in populations as climates around the world change. To predict how populations may respond to such a stress, laboratory experimentation becomes essential. The evolutionary process of adaptation, its innovations and their trade-offs, can be studied in populations experiencing starvation stress. For this purpose outbred populations ofDrosophila melanogasterwere selected for starvation resistance in the laboratory.

After 60+ generations of starvation selection the starvation-selected flies have gone from surviving 2-3 days without food to 12-14 days without food. How this amazing feat of resistance is …

Etudes On Iurids, Vi. Further Revision Of Calchas Birula, 1899 (Scorpiones: Iuridae), With A Description Of A New Genus And Two New Species., Ersen Aydın Yağmur, Michael E. Soleglad, Victor Fet, František Kovařík

Euscorpius

Several new Calchas populations are studied from Turkey, including specimens from Hakkari Province, which borders the northern edge of Iraq. A new genus, Neocalchas, gen. nov., and two new species, Calchas anlasi, sp. nov. and C. kosswigi, sp. nov., are described. The two genera, Calchas and Neocalchas, are diagnosed by their hemispermatophore structure, chelal finger dentition, telson morphometrics and setation, and trichobothrial topology of the pedipalp chela. Genus Calchas Birula, 1899 includes four species: C. anlasi, sp. nov., C. birulai, C. kosswigi, sp. nov., and C. nordmanni; genus …

Spontaneous Male Death And Monogyny In The Dark Fishing Spider Dolomedes Tenebrosus Hentz, 1843 (Araneae, Pisauridae), Steven K. Schwartz

School of Biological Sciences: Dissertations, Theses, and Student Research

Male animals typically attempt to mate with multiple females in order to increase their reproductive success. In some species, however, males instead invest in fertilizing the eggs of a single female. Monogyny (male monogamy) is found in a diverse assemblage of taxa, and recent theoretical work reveals that a male-biased sex ratio can favor the evolution of this relatively rare mating system. We integrate this theoretical framework with field observations and laboratory experiments involving the sexually size dimorphic fishing spider, Dolomedes tenebrosus. Results from mating trials revealed a novel form of self-sacrifice behavior where males spontaneously die when they …

The First Molecular Phylogeny Of Buthidae (Scorpiones), Victor Fet, Benjamin Gantenbein, Alexander Gromov, Graeme Lowe, Wilson R. Lourenço

Euscorpius

The first partial phylogeny of family Buthidae (17 genera) is presented, based on molecular data (16S rRNA mitochondrial DNA). The strong support for a monophyletic Old World group of 13 genera (mainly Palearctic desert forms) is demonstrated, while representative genera from Madagascar (Grosphus) and Southeast Asia (Lychas) group outside, as well as New World genera Centruroides and Rhopalurus. A very strong support is observed for the first time for three groups of Old World genera: (a) Compsobuthus, Mesobuthus, Liobuthus, Kraepelinia; (b) Hottentotta, Buthacus; (c) Orthochirus, Anomalobuthus. Phylogenetic …

Morphology Analysis Supports Presence Of More Than One Species In The “Euscorpius Carpathicus” Complex (Scorpiones: Euscorpiidae), Victor Fet, Michael E. Soleglad

Euscorpius

We investigate a number of scorpion populations from southern and central Europe, commonly classified under a “catch-all” name of Euscorpius carpathicus (L., 1767). This species includes a high number of described subspecies but its composition is not resolved. The detailed morphology analysis in the present paper includes a number of new characters, in particular individually mapped external patellar accessory trichobothria. It suggests that several clearly separated lineages are present. E. carpathicus (L.) is restricted here to geographically marginal populations from Romania (terra typica), which exhibit loss of one trichobothrium in the patellar series em (= 3). Another lineage (Austria, Croatia, …

Two New Andean Species Of Brachistosternus Pocock (Scorpiones: Bothriuridae), Jose A. Ochoa, Louis E. Acosta

Euscorpius

Two new Andean species of the genus Brachistosternus Pocock from southern Peru and northern Chile are described: B. titicaca sp. n. from the Titicaca basin (Departamento Puno, Peru), at 3850-3900 m, and B. quiscapata sp. n. from Departamento Tacna (Peru) and Provincia Arica (Chile), at 3100-3400 m. Both species belong to the subgenus Brachistosternus (Leptosternus) Maury. They are related to the Argentinean species B. (L.) intermedius Lönnberg and B.(L.) montanus Roig Alsina. Comparisons between these four species are provided, including a combination of characters: length/width ratio of metasomal segment V, number of setae of metasomal segment V and tarsus III, …

Etudes On Iurids, V. Further Revision Of Iurus Thorell, 1876 (Scorpiones: Iuridae), With A Description Of A New Genus And Two New Species, Michael E. Soleglad, Victor Fet, František Kovařík, Ersen Aydın Yağmur

Euscorpius

Iurus populations from the Aegean area are studied, including the Greek islands of Crete, Karpathos, Kythira, Rhodes, and Samos. A new genus, Protoiurus gen. nov., and two new species, Protoiurus rhodiensis sp. nov. and P. stathiae sp. nov., are described. The two genera, Iurus and Protoiurus, are diagnosed by their hemispermatophore structure; a cladistic analysis based on this structure is presented. Genus Iurus Thorell, 1876 includes three species: I. dekanum, I. dufoureius, and I. kinzelbachi; genus Protoiurus includes five species: P. asiaticus comb. nov., P. kadleci comb. nov., P. kraepelini comb. nov., P. rhodiensis sp. nov., and P. …