Life Sciences Commons^™

Genomic Adaptations And Evolutionary History Of The Extinct Scimitar-Toothed Cat, Homotherium Latidens, Ross Barnett, Michael V. Westbury, Marcela Sandoval-Velasco, Filipe Garrett Vieira, Sungwon Jeon, Grant Zazula, Michael D. Martin, Simon Y.W. Ho, Niklas Mather, Shyam Gopalakrishnan, Jazmín Ramos-Madrigal, Marc De Manuel, M. Lisandra Zepeda-Mendoza, Agostinho Antunes, Aldo Carmona Baez, Binia De Cahsan, Greger Larson, Stephen J. O'Brien, Eduardo Eizirik, Warren E. Johnson, Klaus Peter Koepfli, Andreas Wilting, Jörns Fickel, Love Dalén, Eline D. Lorenzen, Tomas Marques-Bonet, Anders J. Hansen, Guojie Zhang, Jong Bhak

Biology Faculty Articles

Homotherium was a genus of large-bodied scimitar-toothed cats, morphologically distinct from any extant felid species, that went extinct at the end of the Pleistocene [1–4]. They possessed large, saber-form serrated canine teeth, powerful forelimbs, a sloping back, and an enlarged optic bulb, all of which were key characteristics for predation on Pleistocene megafauna [5]. Previous mitochondrial DNA phylogenies suggested that it was a highly divergent sister lineage to all extant cat species [6–8]. However, mitochondrial phylogenies can be misled by hybridization [9], incomplete lineage sorting (ILS), or sex-biased dispersal patterns [10], which might be especially relevant for Homotherium since widespread …

Genomic Adaptations To Salinity Resist Gene Flow In The Evolution Of Floridian Watersnakes, Rhett M. Rautsaw, Tristan D. Schramer, Rachel Acuña, Lindsay N. Arick, Mark Dimeo, Kathryn P. Mercier, Michael Schrum, Andrew J. Mason, Mark J. Margres, Jason L. Strickland, Christopher L. Parkinson

Publications and Research

The migration-selection balance often governs the evolution of lineages, and speciation with gene flow is now considered common across the tree of life. Ecological speciation is a process that can facilitate divergence despite gene flow due to strong selective pressures caused by ecological differences; however, the exact traits under selection are often unknown. The transition from freshwater to saltwater habitats provides strong selection targeting traits with osmoregulatory function. Several lineages of North American watersnakes (Nerodia spp.) are known to occur in saltwater habitat and represent a useful system for studying speciation by providing an opportunity to investigate gene flow …

Selecting Rootstocks For Utah Peach Orchards, Brent Black, Tiffany Maughan, Taun Beddes, Gregory Reighard

All Current Publications

Peaches are the second most important fruit crop in Utah by acreage. Peach fruit that ripen under our high desert conditions (warm sunny days and cool nights) are valued in the market for their flavor and sugar content. However, peaches are more sensitive than most other fruit crops to our alkaline soil conditions, and often suffer from iron chlorosis.

Commercial peach trees consist of two cultivars or varieties that are grafted together: the scion produces the above ground portion of the tree, and the rootstock forms the roots and the base of the trunk (below ground). The scion variety determines …

The Potential Cost Of Discrimination In Diet Selection By Grazing Herbivores, Cécile Ginane, Bertrand Dumont, Anne Farruggia, Laurent Lanore, Pascal Carrère

IGC Proceedings (1993-2023)

No abstract provided.

Evolution Of Breeding Plumages In Birds: A Multiple-Step Pathway To Seasonal Dichromatism In New World Warblers (Aves: Parulidae), Ryan S. Terrill, Glenn F. Seeholzer, Jared D. Wolfe

Michigan Tech Publications

Ecology and Evolution published by John Wiley & Sons Ltd Many species of birds show distinctive seasonal breeding and nonbreeding plumages. A number of hypotheses have been proposed for the evolution of this seasonal dichromatism, specifically related to the idea that birds may experience variable levels of sexual selection relative to natural selection throughout the year. However, these hypotheses have not addressed the selective forces that have shaped molt, the underlying mechanism of plumage change. Here, we examined relationships between life-history variation, the evolution of a seasonal molt, and seasonal plumage dichromatism in the New World warblers (Aves: Parulidae), a …

استخدام البيولوجيا الجزيئية في عملية الانتقاء الرياضي, شويه بوجمعه, عمر رشدي

Hebron University Research Journal-A (Natural Sciences) - (مجلة جامعة الخليل للبحوث- أ (العلوم الطبيعيه

The study intended to determine the criteria of selection in sports and the factors that help assure a better selection ,in order to discover those excellent physical predispositions earlier according to certain biological criteria , thus time would be saved and efforts would be minimized in learning and training those of high level of performance . Once the learners were well identified in terms of selection in sports , these criteria were divided as follows: -Physical criteria -Physiological criteria -Psychological criteria -Biological criteria Along the different stages , it was noticed that each stage is typical in its characteristics and …

Identifying Positive Selection In Multiple Subspecies Of Xylella Fastidiosa, Daniel Doroteo Flores

Theses and Dissertations

For this study, we will be looking to identify positive selection in eight genomes of the bacterial plant pathogen Xylella fastidiosa. A previous study used a branching method that identified 2 genes with positive selection along with a site-specific method identifying 34 genes showing positive selection. This current study focused specifically on the site-specific method, resulting in 28 genes (of 1,039 tested) showing positive selection. Of the 28 genes showing positive selection, 12 of them come from the pathogenicity, virulence and cellular structural categories. The remaining genes are found in the biosynthesis, metabolism, macro metabolism, and cellular process categories. …

Efficacy Of Current Breeding Programs To Improve North American Native Grass Species For Forage And Conservation Use In The South Eastern United States, Jesse Ira Morrison, Brian Baldwin

IGC Proceedings (1993-2023)

North American native warm-season grasses (NWSG) have received much attention over the last 25 years for their ability to persist under hot, dry conditions and thrive in marginal soils. Native warm season grasses are believed to have been growing on the central and south eastern plains of the United States since the Holocene era (between 11,500 and 2,000 years BP) thus the Southeast is the centre of diversity for these grasses (Casler, 2012). Modern production of many species has been slow to evolve due to inherent dormancy characteristics that hinder germination and establishment. With increased research, many species have shown …

Pernambuco Semiarid Native Rhizobial Populations Nitrogen Fixation Potential With Native Macroptilium, Mércia V. F. Dos Santos, Rerisson Jose Cipriano Dos Santos, Mario De Andrade Lira Jr., Márcio V. Da Cunha, José C. B. Dubeux Jr., Eunice Maria De Souza, Alexandre C. L. De Mello, Vicente Imbrosi Teixeira

IGC Proceedings (1993-2023)

Nitrogen (N) is one of nature´s most abundant elements, accounting for about 78% of the atmospheric gases, but mostly as the inert N₂ form. As such it is not directly available to plants, and is relatively scarce in most agroecosystems. Biological nitrogen fixation (BNF) through diazotrophic bacteria represents ca. 63% of the yearly N input in terrestrial ecosystems (Taiz and Zeiger 2004). Legumes which form effective symbiosis with the diazotrophic group of bacteria commonly known as rhizobia, are a very important source of available N. Tropical forage legumes are usually able to nodulate with a diverse population of rhizobia, …

Central Performance Testing: Purpose, Benefits, Impacts, And Trends, Terry A. Gipson

Professional Agricultural Workers Journal

Abstract The premise of the central performance test is that differences in performance of young animals raised in a common environment are largely attributed to genetics; however, this can be confounded by differences in pre-test environments. It is assumed top-ranking individual’s genetic advantage is a permanent change transferable to the next generation. The popularity of the central performance tests has waxed and waned over the past decades. A strengths-weaknesses-opportunities-threats analysis indicates factors influencing producer participation can include cost, time, geographical coverage, alignment with industry, association support, and relevancy. A second generation of central performance tests with innovative, targeted approaches is …

Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson

Electronic Theses and Dissertations

Studying warning coloration and mimicry is an effective way to understand predator-driven selection and phenotypic diversity. The presence (sympatry) or absence (allopatry) of a toxic model plays a role in shaping mimetic phenotypes. However, the impact of edge sympatry and allopatry on predation of mimetic phenotypes is not well understood. We studied coralsnake mimicry to test how edge sympatry and allopatry affect predation on mimetic phenotypes. Specifically, we tested 1) if overall attack rates varied with edge sympatry of coralsnakes 2) which color patterns conferred a fitness advantage 3) which specific mimetic signal components are important in driving predatory attacks …

Disentangling The Mechanisms Shaping The Surface Ocean Microbiota, Ramiro Logares, Ina M. Deutschmann, Pedro C. Junger, Caterina R. Giner, Anders K. Krabberød, S. B. Schmidt, Laura Rubinat-Ripoll, Mireia Mestre, Guillem Salazar, Clara Ruiz-González, Marta Sebastián, Colomban De Vargas, Silvia G. Acinas, Carlos M. Duarte, Josep M. Gasol, Ramon Massana

Research outputs 2014 to 2021

BACKGROUND: The ocean microbiota modulates global biogeochemical cycles and changes in its configuration may have large-scale consequences. Yet, the underlying ecological mechanisms structuring it are unclear. Here, we investigate how fundamental ecological mechanisms (selection, dispersal and ecological drift) shape the smallest members of the tropical and subtropical surface-ocean microbiota: prokaryotes and minute eukaryotes (picoeukaryotes). Furthermore, we investigate the agents exerting abiotic selection on this assemblage as well as the spatial patterns emerging from the action of ecological mechanisms. To explore this, we analysed the composition of surface-ocean prokaryotic and picoeukaryotic communities using DNA-sequence data (16S- and 18S-rRNA genes) collected during …

The Rattle Call: A Female-Specific Vocalization In Steller's Jays, Kachina L. Rowland

Cal Poly Humboldt theses and projects

While the elaborate songs of male passerines are well documented for their role in intrasexual resource competition and mate attraction, vocalizations used in female competition are poorly understood. Research has suggested that the female-specific rattle call of Steller’s jays (Cyanocitta stelleri) is used in competition for access to a territory and mate. I describe structural properties of the rattle call, and compare life history traits of individual females to rattle call occurrence. I used two rates to quantify rattle call occurrence from 20 females: rattles per observation period (RPO), and proportion of observations with a rattle call (POR) …