Evolution Commons^™

Contributions Of Gene Copy Number Variation To Genome Evolution And Local Adaptation Of The Cyanobacterium Acaryochloris, Amy L. Gallagher

Graduate Student Theses, Dissertations, & Professional Papers

Acaryochloris is a recently discovered genus of cyanobacteria, unique in its use of an uncommon chlorophyll as its major photosynthetic pigment, and in its peculiar genome dynamics. Members of this genus exhibit increased genic copy number variation (CNV), which is thought to be primarily derived from gene duplications and horizontal gene transfer (HGT). Acaryochloris provides an ideal system to explore mechanisms behind maintenance of gene duplicates and the influence of CNV in local adaptation. Here, I propose a mechanism for retention of gene duplicates of the bacterial recombinase, RecA, in Acaryochloris genomes and provide preliminary evidence that these paralogs are …

Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier

Graduate Doctoral Dissertations

The deep sea is the Earth’s largest ecosystem and harbors a unique and largely endemic fauna. Although most research has focused on the ecological mechanisms that allow coexistence, recent studies have begun to investigate how this remarkable fauna evolved.. My work quantifies geographic patterns of genetic variation and investigates potential mechanisms that shape evolution in the deep ocean.

Bathymetric genetic divergence is common in the deep sea with population structure typically decreasing with depth. The evolutionary mechanisms that underlie these patterns are poorly understood. Geographic patterns of genetic variation indicated that the protobranch bivalve Neilonella salicensis was composed of two …

Reef Society And The Tyranny Of Data, Robert Wintner

Animal Sentience

Modern science now approaches divergent processes in many areas, including health assessments of marine eco-systems and social aspects of marine species. Scientific data have long enjoyed a reputation for objectivity but incidents of science-for-hire, data spinning/skewing and political jading are more frequent than ever. In the field of reef creature sensitivity, technical treatises can “logically” explain away what a person of average education can clearly observe on any given reef. Western medicine discounted anecdotal evidence of any cure outside the 4% margin of error until those cures demanded attention and in some cases application. Modern science must now enter an …

Still Wondering How Flesh Can Feel, Gwen J. Broude

Animal Sentience

Reber believes he has simplified Chalmers’s “hard problem” of consciousness by arguing that subjectivity is an inherent feature of biological forms. His argument rests on the related notions of continuity of mind and gradual accretion of capacities across evolutionary time. These notions need to be defended, not just asserted. Because Reber minimizes the differences in mental faculties among species across evolutionary time, it becomes easier to assert, and perhaps believe, that sentience is already present in early biological forms. The more explicit we are about the differences among these mental faculties and the differences across species, the less persuasive is …

Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang

Master's Theses

Why do some species have broad geographic distributions, while other species are confined to a narrow distribution? Species age, ecological niche, or dispersal traits may help explain why some insular species are abundant and found on many islands, while others are rare and restricted to one island. In this study, I inferred a robust, time-calibrated phylogeny of the Hawaiian Psychotria, using two nuclear and eight chloroplast loci, sampling 67 individuals. I coupled my phylogenetic hypothesis with climatic data, ecological niche modeling, and morphological dispersal characteristics to explain the variation in number of islands occupied by each species. My inferred phylogeny …

Changes In Male Hunting Returns, Raymond B. Hames

Department of Anthropology: Faculty Publications

Research on changes in male hunting among hunter-gatherers addresses two important issues in early human evolution: the nature of the family and trade-offs in mating and parenting effort as well as the development of embodied capital. In the hunter-gatherer literature, there is a debate about the function of male hunting that has implications for understanding the role males play in the evolution of the pair bond. The traditional model argues that male hunting and other economic activities are forms of male provisioning or parenting effort designed to enhance a man’s fitness through his wife’s reproduction and the survivorship of their …

Review Of Northwestern African Buthacus, With Description Of Buthacus Stockmanni Sp. N. From Morocco And Western Sahara (Scorpiones, Buthidae), František Kovařík, Graeme Lowe, František Šťáhlavský

Euscorpius

Northwestern African Buthacus species are revised. Buthacus stockmanni sp. n. from Morocco and Western Sahara is described and fully complemented with color photos of live and preserved specimens, as well as their habitat. The hemispermatophore of B. stockmanni sp. n. is illustrated and described. In addition to morphology and hemi-spermatophores, we also describe the karyotypes of B. stockmanni sp. n. (2n=20). B. stockmanni sp. n. is compared with B. occidentalis Vachon, 1953 and B. ziegleri Lourenço, 2000. Both these species are differentiated from B. stockmanni sp. n. geographically and morphologically. The male of B. stockmanni sp. n. has fingers of …

First Report Of Lissothus Occidentalis Vachon, 1950 (Scorpiones: Buthidae) From Morocco And Western Sahara, With Notes On Ecology And Captive Breeding, Mark Stockmann, Carlos Turiel, Felix Althoff, Graeme Lowe, František Kovařík

Euscorpius

Genus Lissothus Vachon, 1948 represented by L. occidentalis Vachon, 1950 is reported for the first time from four localities in Morocco and the Western Sahara. We provide a revised diagnosis of L. occidentalis, fully complemented with color photos of live and preserved specimens. Hemispermatophore is also illustrated and described in detail. Furthermore, we describe aspects of the ecology of this species, and provide photos of collection sites and habitats. We also report on the reproductive biology of this species based on captive breeding and rearing. and provide the first envenomation report for the species.

Animals Aren’T Persons, But Is It Time For A Neologism?, Helen Steward

Animal Sentience

Mark Rowlands argues that at least some animals are persons, based on the idea that (i) many animals have a property he calls “pre-reflective awareness,” (ii) the capacity for pre-reflective awareness is sufficient to satisfy the traditional Lockean definition of personhood, and (iii) satisfaction of the traditional Lockean definition of personhood is sufficient for being a person. I agree with (i) and can see that there is a persuasive case for (ii), but I think the case against (iii) blocks the conclusion that animals are persons. I suggest that we may need instead to coin a neologism in order to …

Reber’S Caterpillar Offers No Help, Carl Safina

Animal Sentience

Reber’s target article “Caterpillars, consciousness and the origins of mind” seems only to shift but not to address the question of where the mind is and how minds occur.

Evolution In Light Of Mitonuclear Landscapes: An Examination Of Mitochondrial Replacement In Killifish (Fundulus Spp.), Stephen D. Flanagan

Dissertations

The mitochondria are responsible for the bulk of energy production in eukaryotes. They possess their own genome that works in conjunction with the nuclear genome to accomplish the extraordinarily important task of energy conversion. When species hybridize there will be a mismatch in evolutionary histories between these two genomes. The deleterious interactions of these genomes have been studied in great detail (i.e. hybrid breakdown). However, little work has been conducted to understand the population genetic, and morphological consequences of wide-ranging replacement. The Fundulus notatus complex is comprised of 3 species: F. notatus, F. olivaceus, and F. euryzonus. …

Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs

Graduate Theses and Dissertations

Hybridization is neither simplistic nor phylogenetically constrained, and post hoc introgression can have profound evolutionary effects. Most studies have focused on tractable model systems, rather than organisms with complicated phylogenetic histories. Finescale Sucker (genus Catostomus) in western North America is recognized as a paradigm of fish hybridization. Yet, its extent of historic and contemporary introgression is largely unstudied, an aspect that impedes the resolution of its phylogeny as a baseline for conservation. To explore reticulation in this group, I assayed variation of 20 Catostomus species across temporal and geographic scales by analyzing hundreds of samples and employing a combination of …

Minority Middle And High School Students' Interest In Science: An Exploration Of Teachers' Perceptions, Caroline Makere

Dissertations

A high school teacher conducted a study about minority middle and high school students’ interest in science. The problem was to find out why African American and Hispanic students were showing very little interest in science. The researcher used four middle school science teachers and nine high school science teachers, all from inner city schools in a big city of the Midwest United States except for one middle school teacher from a nearby suburb. The participants answered a survey questionnaire followed with a face-to-face recorded interview. The findings of the study confirmed that students showed little interest in science due …

Sexual Determination From Frontal Sinus Analysis In A Subadult Population Using Archival Radiographic Records, Erica Crosta

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study is to use the improved imaging capability of cone-beam computerized tomography (CBCT) to investigate the development and sexual dimorphism of the frontal sinus and surrounding supraorbital region in the subadult population of urban Southern Nevada. CBCT radiographs were obtained from the UNLV School of Dental Medicine archival dental records. Five hundred and fifty six of these radiographs were reviewed for the study. Two hundred and sixteen patients (92 males, 124 females) between the ages of 7 and 20 years were included based on inclusion/exclusion criteria. Samples were categorized into 3 subadult age groups for analysis: …

Behavioral Reactions To Emotional And Physical Infidelity: An Evolutionary Perspective, Mandy Walsh Walsh

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis examined the effects of sex and type of partner infidelity, including both physical (i.e., sexually involved with another person) and emotional (i.e., emotionally involved with another person) infidelity, on mate abandonment behaviors. Previous research has demonstrated sex differences in emotional responses to infidelity, where men react more negatively to physical infidelity and women react more negatively to emotional infidelity. While various studies have investigated perceived behavioral reactions using imagined scenarios, this study expands current research by utilizing actual retrospective reports. It was hypothesized that males would engage in significantly more mate abandonment behaviors after experiencing a physical infidelity, …

Two New Species Of Euscorpius Thorell, 1876 From Southern Turkey (Scorpiones: Euscorpiidae), Gioele Tropea, Ersen Aydın Yağmur

Euscorpius

Two new species of scorpion of the genus Euscorpius Thorell, 1876 are described from southern Turkey based on morphological ratio and trichobothrial data. E. hakani sp. n. from Mt. Eşeler, in Denizli Province in southwestern Turkey and E. aladaglarensis sp. n. from the Aladağlar Mts., in Niğde, Kayseri, and Adana Provinces. With the description of two new taxa, 17 species of Euscorpius are currently recognized in Turkey.

Insect Consciousness: Commitments, Conflicts And Consequences, Colin Klein, Andrew B. Barron

Animal Sentience

Our target article, “Insects have the capacity for subjective experience,” has provoked a diverse range of commentaries. In this response we have collated what we see as the major themes of the discussion. It is clear that we differ from some commentators in our commitments to what subjective experience is and what the midbrain is capable of. Here we clarify where we stand on those points and how our view differs from some other influential perspectives. The commentaries have highlighted the most lively areas of disagreement. We revisit here the debates surrounding whether the cortex is essential for any form …

Problems Of Multi-Species Organisms: Endosymbionts To Holobionts, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The organism is one of the fundamental concepts of biology and has been at the center of many discussions about biological individuality, yet what exactly it is can be confusing. The definition that we find generally useful is that an organism is a unit in which all the subunits have evolved to be highly cooperative, with very little conflict. We focus on how often organisms evolve from two or more formerly independent organisms. Two canonical transitions of this type—replicators clustered in cells and endosymbiotic organelles within host cells—demonstrate the reality of this kind of evolutionary transition and suggest conditions that …

Consciousness And Evolutionary Biology, Yew-Kwang Ng

Animal Sentience

Reber’s axiom: “Any organism with flexible cell walls, a sensitivity to its surrounds and the capacity for locomotion will possess the biological foundations of mind and consciousness” does not seem to be supported by things we know and the logic of evolutionary biology. The latter leads to the conclusion that conscious species are flexible in their behavior (rather than in their cell walls), as argued in Ng (1995, 2016). Locomotion may be completely hard-wired and need not involve consciousness. It is hard enough to explain how consciousness could emerge in a sophisticated brain: Isn’t it a harder problem to show …

The Difference Between Conscious And Unconscious Brain Circuits, Ezequiel Morsella, Zaviera Reyes

Animal Sentience

Theoretical frameworks in which consciousness is an inherent property of the neuron must account for the contrast between conscious and unconscious processes in the brain and address how neural events can ever be unconscious if consciousness is a property of all neurons. Other approaches have sought answers regarding consciousness by contrasting conscious and unconscious processes and through investigating the complex interactions between the two kinds of processes, as occurs most notably in human voluntary action. In voluntary action, consciousness is associated most, not with motor control or low-level perceptual processing, but with the stage of processing known as action selection.