Evolution Commons^™

Estimating The Frequency Of Sexual Reproduction In The Diatom Stephanodiscus Niagarae, Ann W. Dickens

Biological Sciences Undergraduate Honors Theses

Diatoms are single-celled micro-algae with cell walls composed of silica, that reproduce in a way that results in a decrease in cell size after each round of mitotic (asexual) division. A cell cannot continue to shrink indefinitely, so when the average size of the population reaches a critical threshold, diatoms reproduce sexually and restore their maximal size. It is unclear, however, how frequently diatoms undergo sexual reproduction in nature. As a proxy for sexual reproduction, I monitored changes in cell size of a population of the diatom Stephanodiscus niagarae from the plankton community of Lake Fayetteville (Arkansas, USA). Weekly sampling …

Physiology And Genetics Of Starvation-Selected Drosophila Melanogaster, Christopher Michael Hardy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, organisms have evolved to survive in stressful environments. This has driven organisms to adopt a wide range of unique adaptations. Investigating the mechanistic basis of these adaptations is an important tool for discovery that has led to major advances in science and medicine.

We study how organisms survive life without food, or starvational stress. Environmental stressors have shaped the quantity and quality of food sources across the globe. This has led to vast differences in the ability of some organisms to tolerate starvation over others. Many researchers have used Drosophila melanogaster as a model to study global patterns …

Nuclear Architecture And Patterns Of Molecular Evolution Are Correlated In The Ciliate Chilodonella Uncinata, Xyrus X. X. Maurer-Alcala, Laura A. Katz

Biological Sciences: Faculty Publications

The relationship between nuclear architecture and patterns of molecular evolution in lineages across the eukaryotic tree of life is not well understood, partly because molecular evolution is traditionally explored as changes in base pairs along a linear sequence without considering the context of nuclear position of chromosomes. The ciliate Chilodonella uncinata is an ideal system to address the relationship between nuclear architecture and patterns of molecular evolution as the somatic macronucleus of this ciliate is composed of a peripheral DNA-rich area (orthomere) and a DNA-poor central region (paramere) to form a “heteromeric” macronucleus. Moreover, because the somatic chromosomes of C. …

Mass Extinctions Increase Evenness Of Genus Diversity Across Ecological Modes, Catherine Lau

Creative Activity and Research Day - CARD

In the Big Five mass extinctions, species were eliminated from ecological modes (groups of species in the same habitat with the same motility method and feeding strategy) with greater species diversity preceding these events. Using Knope et al.'s (2015) data set of 18,621 marine animal genera, I asked: When diversity rebounds, does it recover to a similar distribution of genus diversity across modes or to a more even distribution spanning different modes? With each event, the difference in diversity among modes decreases, so evenness increases over time. Mass extinctions contribute to the broad range of diversity we see today.

Virus-Host Co-Evolution: Determining The Origin Of Human Cytomegalovirus Us27 And Us28, Jessica A. Scarborough, Juliet Spencer, John Paul

Creative Activity and Research Day - CARD

G protein-coupled receptors (GPCR) are the largest family of cell surface proteins, found in organisms from yeast to humans. Human cytomegalovirus (HCMV) is a widespread pathogen that is particularly skilled at evading immune detection and defense mechanisms, largely due to extensive co-evolution with its host’s immune system. One aspect of this co-evolution involves the acquisition of four virally encoded GPCR homologs: US27, US28, UL33 and UL78. In this research, phylogenetic analysis was used to investigate the origins of the US27 and US28 genes, which are adjacent in the viral genome. The results indicate that both US27 and US28 share the …

A New Species Of Euscorpius Thorell, 1876 From Mount Honaz In Southwestern Turkey (Scorpiones: Euscorpiidae), Gioele Tropea, Ersen Aydın Yağmur, Lydia Karampatsou, Aristeidis Parmakelis, Fatih Yeşilyurt

Euscorpius

A new species of scorpion, Euscorpius honazicus sp. n., is described from Mount Honaz, in the province of Denizli, in southwestern Turkey, based on morphological and molecular evidence, increasing to 14 the Euscorpius species currently recognized in Turkey.

The First Record Of Malformed Pectines In Genus Euscorpius (Scorpiones: Euscorpiidae), Miroslav Šarić, Jovana Tomić

Euscorpius

A teratological change in a pectinal organ of Euscorpius cf. carpathicus (C. L. Koch, 1837) from Serbia had been examined using SEM (Scanning Electron Microscopy), and compared to specimens with normally developed pectines. Possible reasons for this anomaly are discussed.

No Effect Of Blood Sampling Or Phytohaemagglutinin Injection On Postfledging Survival In A Wild Songbird, Emerson Keith Bowers, Charles F. Thompson, Scott K. Sakaluk

Faculty Publications – Biological Sciences

The injection of phytohaemagglutinin (PHA) and sampling of blood are widelyused in studies of wild vertebrates to assess components of immune and endo-crine function and health state and to obtain genetic material. Despite the per-vasive use of these techniques in the life sciences, their potential effects onsurvival are rarely considered. For example, whether injection of the immuno-gen PHA into body parts critical for locomotion (e.g., the prepatagium, or wingweb, in birds) affects survival has not been tested. Here, we test whether injec-tion of PHA into the wing web and blood sampling from nestling house wrensaffects their subsequent recruitment and survival …

Evotext: A New Tool For Analyzing The Biological Sciences, Grant Ramsey, Charles H. Pence

Faculty Publications

We introduce here evoText, a new tool for automated analysis of the literature in the biological sciences. evoText contains a database of hundreds of thousands of journal articles and an array of analysis tools for generating quantitative data on the nature and history of life science, especially ecology and evolutionary biology. This article describes the features of evoText, presents a variety of examples of the kinds of analyses that evoText can run, and offers a brief tutorial describing how to use it.

Assessing The Impact Of Historical Story Telling On Student Learning Of Natural Selection, Janice Marie Fulford

Dissertations

Research suggests that because of its historical nature, the learning of evolutionary biology is problematic compared to that of other science disciplines. While explanations used in historical sciences often employ historical narratives, which are distinct from narratives in other contexts, such as stories, the two types of narratives have structural similarities that suggest the potential role of stories based in the history of science for the teaching of evolutionary biology. Stephen Klassen, a prominent science educator, has studied how stories from the history of physics can promote the learning of and attitudes towards science. Klassen’s pioneering work identifies structural components …

The Line Drawn On Pain Still Holds, Bjorn H. Merker

Animal Sentience

The many substantive criticisms raised against Key by me and by many of the other commentators will not disappear by ignoring or waving them aside with meta-discourse about anthropomorphism, just-so stories, or celestial teapots. The conceptual edifice Key inhabits and defends with such gusto may look like an impregnable fortress from the inside – and Key behaves as if it were. From the outside, however, it looks more like a ramshackle structure gaping with holes and pieced together from imperfectly understood neuroscience and often faulty literature citations.

Slavery, Welfare And The Sixth Extinction, Stephen R. Clark

Animal Sentience

Ng’s laudable concern for animal welfare would be welcome to any sensible slave-owner wishing to preserve his investment. What welfarism – for slave-owners and animal husbandmen – fails to call into question is whether we have the right to breed, hold captive and kill animals at all: If it matters, as the widely recognized slogan of ‘Five Freedoms’ suggests, that animals have the chance to live a ‘normal’ life, then more matters than keeping them ‘happy’ in subjection. Their lives – and also the lives of wild things – also deserve respect.

Scorpions Of Sri Lanka (Scorpiones: Buthidae, Chaerilidae, Scorpionidae) With Description Of Four New Species Of The Genera Charmus Karsch, 1879 And Reddyanus Vachon, 1972, Stat. N., František Kovařík, Graeme Lowe, Kithsiri B. Ranawana, David Hoferek, V. A. Sanjeewa Jayarathne, Jana Plíšková, František Šťáhlavský

Euscorpius

Data about all 18 known scorpion species of Sri Lanka are summarized. All previously known species were newly collected and four new species discovered during a scorpiological expedition in 2015. Information is provided about their taxonomy, distribution, ecology, and reproductive biology, fully complemented with color photos of live and preserved specimens, as well as their habitat. Subgenus Isometrus (Reddyanus) Vachon, 1972 is elevated to genus level, Reddyanus stat. n., supported by new characters of setation on leg tarsomere II and hemi-spermatophore morphology. Charmus saradieli sp. n., Reddyanus ceylonensis sp. n., R. jayarathnei …

Wild Animal Suffering And Vegan Outreach, Eze Paez

Animal Sentience

Ng’s strategic proposal seems to downplay the potential benefits of advocacy for wild animals and omit what may be the most effective strategy to reduce the harms farmed animals suffer: vegan outreach.

To Minimize Animal Suffering, Broaden The Definition Of Animal Cruelty, Eleonora Gullone

Animal Sentience

Mandatory veterinary reporting of suspected abuse might discourage caregivers from seeking treatment for their injured animals. Animal abusers are more likely to be brought to justice by raising community awareness about the link between animal cruelty and human violence and its implications for the wellbeing of both humans and animals. Commonly accepted definitions of animal cruelty focus only on cruelty that is socially unacceptable, excluding an enormous amount of unnecessary animal suffering caused by humans. Only by broadening the definition of animal cruelty can we bring about the cultural change necessary to minimize this animal suffering.

Population Genetic Divergence Of Isle Royale Pearl Dace, Margarita Margariscus (Cyprinidae)., John F. Elder Jr., Jack R. Martin, Isaac J. Schlosser, Larry Kallemeyn

Georgia Journal of Science

In 1949, Hubbs and Lagler described morphological variation among pearl dace (Margariscus margarita) of inland lakes on Isle Royale, Michigan. For Harvey Lake, Hubbs and Lagler, proposed that pearl dace were sufficiently morphologically distinct to warrant subspecific status. They argued that divergence of the Harvey Lake pearl dace was due to allopatric differentiation in isolation from lower elevation lakes. Harvey Lake has been isolated by elevation from lower elevation lakes for approximately 10 to 15 thousand years. No genetic studies have been done on Isle Royale pearl dace to evaluate this hypothesis to date. Here we report the analysis of …

Molecular Evolution And Functional Divergence Of Trace Amine–Associated Receptors, Seong-Il Eyun, Hideaki Moriyama, Federico G. Hoffmann, Etsuko N. Moriyama

School of Biological Sciences: Faculty Publications

Trace amine-associated receptors (TAARs) are a member of the G-protein-coupled receptor superfamily and are known to be expressed in olfactory sensory neurons. A limited number of molecular evolutionary studies have been done for TAARs so far. To elucidate how lineage-specific evolution contributed to their functional divergence, we examined 30 metazoan genomes. In total, 493 TAAR gene candidates (including 84 pseudogenes) were identified from 26 vertebrate genomes. TAARs were not identified from non-vertebrate genomes. An ancestral-type TAAR-like gene appeared to have emerged in lamprey.We found four therian-specific TAAR subfamilies (one eutherian-specific and three metatherian- specific) in addition to previously known nine …

A Phylogenomic Assessment Of Ancient Polyploidy And Genome Evolution Across The Poales, Michael R. Mckain, Haibao Tang, Joel R. Mcneal, Et Al.

Faculty Articles

Comparisons of flowering plant genomes reveal multiple rounds of ancient polyploidy characterized by large intra-genomic syntenic blocks. Three such whole genome duplication (WGD) events, designated as rho (ρ), sigma (σ), and tau (τ), have been identified in the genomes of cereal grasses. Precise dating of these WGD events is necessary to investigate how they have influenced diversification rates, evolutionary innovations, and genomic characteristics such as the GC profile of protein coding sequences. The timing of these events has remained uncertain due to the paucity of monocot genome sequence data outside the grass family (Poaceae). Phylogenomic analysis of protein coding genes …

Session D-1: Science And Spaghetti Monsters: Addressing The Ethical Issues And Controversy Related To Genomics And Evolution In The Biology Classroom, Sarah O'Leary-Driscoll

Professional Learning Day

As science teachers, we may shy away from addressing the controversy surrounding particular topics in our classrooms in order to maintain focus on content. However, the real world context of knowledge is essential, and the performance expectations in the life sciences as outlined in the NGSS state that students should be able to discuss the ethical issues related to genetic modifications and the nature of science. We will discuss ideas for how to address these topics effectively and help our students understand their importance beyond academics in our global community.

New Data On The Distribution Of Butheoloides Littoralis Lourenço, Touloun Et Boumezzough, 2011 (Scorpiones: Buthidae) Oulaid, Oulaid Touloun, Moulay Abdelmonaim El Hidan, Ali Boumezzough

Euscorpius

Morocco is the region in Africa with the highest diversity of Butheoloides Hirst, 1925 species. Until now, the total number of species of this genus known from Morocco is raised to five. A field study conducted in southern Morocco discovered a new specimen of Butheloides littoralis in the Tighmi region (southeast of Tiznit), the most continental site of this species in Morocco. This specimen is the third of this endemic species of Morocco but it is the first male discovered.