Life Sciences Commons^™

Biogeographic Affiliation And Centers Of Richness As Predictors Of Elevational Range-Size Patterns For Malesian Flora, Melissa Whitman, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Our goal was to interrogate the idea that “mountain passes are higher in the tropics” by investigating ecological and biogeographic drivers of elevational range-sizes patterns among equatorial flora. We used herbarium records for 60 species-rich plant families, representing 18 535 species total, to estimate distributions over a 4500 m elevational gradient. For each family, we estimated the change in average range-sizes with increasing elevation (i.e. Rapoport's rule, abbreviated as ERR) and quantified 15 metrics of familial richness distribution, evolutionary age, and biogeographic affiliation. We visualized covariation across families using phylogenetic principal components analysis (pPCA). We then evaluated how family-level ERR …

Enzyme Kinetics Of Deoxyuridine Triphosphatase From Western Corn Rootworm, Carlos Riera‑Ruiz, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

Objective The Western corn rootworm (WCR), Diabrotica virgifera virgifera, is a highly adaptable insect pest that has evolved resistance to a variety of control strategies, including insecticides. Therefore, it is interesting to examine how housekeeping proteins in WCR have been changed under WCR-controlling strategies. In this study, we focused on one of such proteins in WCR, a ubiquitous enzyme 5’-triphosphate nucleotidohydrolase (dUTPase). In the thymidine synthetic pathway, dUTPase hydrolyzes deoxyuridine triphosphate (dUTP) and supplies the substrate, deoxyuridine monophosphate, for the thymidylate synthase (TS). It decreases the cellular content of uracil, reducing uracil misincorporation into DNA. Suppressing the dUTPase activity, …

Enzyme Kinetics Of Deoxyuridine Triphosphatase From Western Corn Rootworm, Carlos Riera‑Ruiz, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

Objective The Western corn rootworm (WCR), Diabrotica virgifera virgifera, is a highly adaptable insect pest that has evolved resistance to a variety of control strategies, including insecticides. Therefore, it is interesting to examine how housekeeping proteins in WCR have been changed under WCR-controlling strategies. In this study, we focused on one of such proteins in WCR, a ubiquitous enzyme 5’-triphosphate nucleotidohydrolase (dUTPase). In the thymidine synthetic pathway, dUTPase hydrolyzes deoxyuridine triphosphate (dUTP) and supplies the substrate, deoxyuridine monophosphate, for the thymidylate synthase (TS). It decreases the cellular content of uracil, reducing uracil misincorporation into DNA. Suppressing the dUTPase activity, …

Genome Sequences Of Six Cluster Ct And Two Cluster Dj Bacteriophages That Infect Gordonia Rubripertincta, Xavier F. Rodriguez, Daniel C. Williams, Catherine P. Chia

School of Biological Sciences: Faculty Publications

We report the genome sequences of eight bacteriophages isolated using Gordonia rubripertincta NRRL B-16540-SEA. Based on gene content similarity to phages in the Actinobacteriophage database, six of the phages are assigned to phage cluster CT while two are assigned to cluster DJ.

To What Extent Do Physiological Tolerances Determine Elevational Range Limits Of Mammals?, Jay F. Storz, Graham R. Scott

School of Biological Sciences: Faculty Publications

A key question in biology concerns the extent to which distributional range limits of species are determined by intrinsic limits of physiological tolerance. Here, we use common-garden data for wild rodents to assess whether species with higher elevational range limits typically have higher thermogenic capacities in comparison to closely related lowland species. Among South American leaf-eared mice (genus Phyllotis), mean thermogenic performance is higher in species with higher elevational range limits, but there is little among-species variation in the magnitude of plasticity in this trait. In the North American rodent genus Peromyscus, highland deer mice (Peromyscus maniculatus …

Temperature And Predators As Interactive Drivers Of Community Properties, John Delong, Kyle E. Coblentz, Stella F. Uiterwaal, Chika Akwani, Miranda E. Salsbery

School of Biological Sciences: Faculty Publications

The effects of warming on ecological communities emerge from a range of potentially asymmetric impacts on individual physiology and development. Understanding these responses, however, is limited by our ability to connect mechanisms or emergent patterns across the many processes that drive variation in demography. Further complicating this understanding is the gain or loss of predators to many communities, which may interact with changes in temperature to drive community change. Here we conducted a factorial warming and predation experiment to test generalized predictions about responses to warming. We used microcosms with a range of protists, rotifers, and a gastrotrich, with and …

Temperature And Predators As Interactive Drivers Of Community Properties, John P. Delong, Kyle E. Coblentz, Stella F. Uiterwaal, Chika Akwani, Miranda E. Salsbery

School of Biological Sciences: Faculty Publications

The effects of warming on ecological communities emerge from a range of potentially asymmetric impacts on individual physiology and development. Understanding these responses, however, is limited by our ability to connect mechanisms or emergent patterns across the many processes that drive variation in demography. Further complicating this understanding is the gain or loss of predators to many communities, which may interact with changes in temperature to drive community change. Here we conducted a factorial warming and predation experiment to test generalized predictions about responses to warming. We used microcosms with a range of protists, rotifers, and a gastrotrich, with and …

Effects Of Large Mammal Exclusion On Seedling Communities Depend On Plant Species Traits And Landscape Protection In Human-Modified Costa Rican Forests, Nohemi Huanca-Nuñez, Robin L. Chazdon, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

1. Large terrestrial herbivorous mammals (LTH-mammals) influence plant community structure by affecting seedling establishment in mature tropical forests. Many of these LTH-mammals frequent secondary forests, but their effects on seedling establishment in them are understudied, hindering our understanding of how LTH-mammals influence forest regeneration in human-modified landscapes.

2. We tested the hypothesis that the strength of LTH-mammals' effects on seedling establishment depends on landscape protection, forest successional stage and plant species' traits using a manipulative field experiment in six 1-ha sites with varying successional age and landscape protection. In each site, we established 40 seedling plot-pairs, with one plot excluding LTH-mammals and …

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Effects Of Large Mammal Exclusion On Seedling Communities Depend On Plant Species Traits And Landscape Protection In Human-Modified Costa Rican Forests, Nohemi Huanca-Nuñez, University Of Connecticut, University Of The Sunshine Coast, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

1. Large terrestrial herbivorous mammals (LTH-mammals) influence plant community structure by affecting seedling establishment in mature tropical forests. Many of these LTH-mammals frequent secondary forests, but their effects on seedling establishment in them are understudied, hindering our understanding of how LTH-mammals influence forest regeneration in human-modified landscapes.
2. We tested the hypothesis that the strength of LTH-mammals' effects on seedling establishment depends on landscape protection, forest successional stage and plant species' traits using a manipulative field experiment in six 1-ha sites with varying successional age and landscape protection. In each site, we established 40 seedling plot-pairs, with one plot excluding LTH-mammals and …

Genome Sequences Of Six Cluster Ct And Two Cluster Dj Bacteriophages That Infect Gordonia Rubripertincta, Xavier F. Rodriguez, Daniel C. Williams, Catherine P. Chia

School of Biological Sciences: Faculty Publications

We report the genome sequences of eight bacteriophages isolated using Gordonia rubripertincta NRRL B-16540-SEA. Based on gene content similarity to phages in the Actinobacteriophage database, six of the phages are assigned to phage cluster CT while two are assigned to cluster DJ.

Comparative Polar And Lipid Plasma Metabolomics Differentiate Kshv Infection And Disease States, Sara R. Privatt, Camila Pereira Braga, Alicia Johnson, Salum J. Lidenge, Luke Berry, John R. Ngowi, Owen Ngalamika, Andrew G. Chapple, Julius Mwaiselage, Charles Wood, John T. West, Jiri Adamec

School of Biological Sciences: Faculty Publications

Background Kaposi sarcoma (KS) is a neoplastic disease etiologically associated with infection by the Kaposi sarcoma-associated herpesvirus (KSHV). KS manifests primarily as cutaneous lesions in individuals due to either age (classical KS), HIV infection (epidemic KS), or tissue rejection preventatives in transplantation (iatrogenic KS) but can also occur in individuals, predominantly in sub-Saharan Africa (SSA), lacking any obvious immune suppression (endemic KS). The high endemicity of KSHV and human immunodeficiency virus-1 (HIV) co-infection in Africa results in KS being one of the top 5 cancers there. As with most viral cancers, infection with KSHV alone is insufficient to induce tumorigenesis. …

Comparative Polar And Lipid Plasma Metabolomics Differentiate Kshv Infection And Disease States, Sara R. Privatt, Camila Pereira Braga, Alicia Johnson, Salum J. Lidenge, Luke Berry, John R. Ngowi, Owen Ngalamika, Andrew G. Chapple, Julius Mwaiselage, Charles Wood, John T. West, Jiri Adamec

School of Biological Sciences: Faculty Publications

Background Kaposi sarcoma (KS) is a neoplastic disease etiologically associated with infection by the Kaposi sarcoma-associated herpesvirus (KSHV). KS manifests primarily as cutaneous lesions in individuals due to either age (classical KS), HIV infection (epidemic KS), or tissue rejection preventatives in transplantation (iatrogenic KS) but can also occur in individuals, predominantly in sub-Saharan Africa (SSA), lacking any obvious immune suppression (endemic KS). The high endemicity of KSHV and human immunodeficiency virus-1 (HIV) co-infection in Africa results in KS being one of the top 5 cancers there. As with most viral cancers, infection with KSHV alone is insufficient to induce tumorigenesis. …

Loss Of Flockmates Weakens Winter Site Fidelity In Golden-Crowned Sparrows (Zonotrichia Atricapilla), Anastasia E. Madsen, Bruce E. Lyon, Alexis S. Chaine, Theadora A. Block, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Animal social interactions have an intrinsic spatial basis as many of these interactions occur in spatial proximity. This presents a dilemma when determining causality: Do individuals interact socially because they happen to share space, or do they share space because they are socially linked? We present a method that uses demographic turnover events as a natural experiment to investigate the links between social associations and space use in the context of interannual winter site fidelity in a migratory bird. We previously found that golden-crowned sparrows (Zonotrichia atricapilla) show consistent flocking relationships across years, and that familiarity between individuals …

Transcriptional Regulation Of The Synthesis And Secretion Of Farnesol In The Fungus Candida Albicans: Examination Of The Homann Transcription Regulator Knockout Collection, Daniel Gutzmann, Jaxon J. Kramer, Brigid M. Toomey, Cory Honsinger Thomas Boone, Audrey L. Atkin, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants …

Transcriptional Regulation Of The Synthesis And Secretion Of Farnesol In The Fungus Candida Albicans: Examination Of The Homann Transcription Regulator Knockout Collection, Daniel Gutzmann, Jaxon J. Kramer, Brigid M. Toomey, Cory Honsinger Thomas Boone, Audrey L. Atkin, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants produced …

Preclinical Characterization Of The Efficacy And Safety Of Biologic N‑001 As A Novel Pain Analgesic For Post‑Operative Acute Pain Treatment, Derek Allen, Samerender Nagam Hanumantharao, Rylie Mcdonell, Karen‑Amanda Irvine, Peyman Sahbaie, David Clark, Paul H. Blum

School of Biological Sciences: Faculty Publications

Inhibition of actin remodeling in nerves modulates action potential propagation and therefore could be used to treat acute pain. N-001 is a novel protein analgesic engineered from several C. Botulinum toxins. N-001 targets sensory neurons through ganglioside GT1b binding and ADP-ribosylates G-actin reducing actin remodeling. The activity and efficacy of N-001 was evaluated previously in vitro and in a mouse inflammatory pain model. To assess the relevance of N-001 for treatment of acute post-surgical pain, the current study evaluated the efficacy of N-001 in a mouse hind-paw incision model by periincisional and popliteal nerve block administration combined with mechanical …

Rewiring Of Aminoacyl-Trna Synthetase Localization And Interactions In Plants With Extensive Mitochondrial Trna Gene Loss, Jessica M. Warren, Amanda K. Broz, Ana Martinez-Hottovy, Christian Elowsky, Alan C. Christensen, Daniel B. Sloan

School of Biological Sciences: Faculty Publications

The number of tRNAs encoded in plant mitochondrial genomes varies considerably. Ongoing loss of bacterial-like mitochondrial tRNA genes in many lineages necessitates the import of nuclear-encoded counterparts that share little sequence similarity. Because tRNAs are involved in highly specific molecular interactions, this replacement process raises questions about the identity and trafficking of enzymes necessary for the maturation and function of newly imported tRNAs. In particular, the aminoacyl-tRNA synthetases (aaRSs) that charge tRNAs are usually divided into distinct classes that specialize on either organellar (mitochondrial and plastid) or nuclear-encoded (cytosolic) tRNAs. Here, we investigate the evolution of aaRS subcellular localization in …

Essential And Recurrent Roles For Hairpin Rnas In Silencing De Novo Sex Chromosome Conflict In Drosophila Simulans, Jeffrey Vedanayagam, Marion Herbette, Holly Mudgett, Ching-Jung Lin, Chun- Ming Lai, Caitlin Mcdonough-Goldstein, Stephen Dorus, Benjamin Loppin, Colin D. Meiklejohn, Raphaëlle Dubruille, Eric C. Lai

School of Biological Sciences: Faculty Publications

Meiotic drive loci distort the normally equal segregation of alleles, which benefits their own transmission even in the face of severe fitness costs to their host organism. However, relatively little is known about the molecular identity of meiotic drivers, their strategies of action, and mechanisms that can suppress their activity. Here, we present data from the fruitfly Drosophila simulans that address these questions. We show that a family of de novo, protamine- derived X-linked selfish genes (the Dox gene family) is silenced by a pair of newly emerged hairpin RNA (hpRNA) small interfering RNA (siRNA)-class loci, Nmy and Tmy. …

Characterization Of A Novel Polyextremotolerant Fungus, Exophiala Viscosa, With Insights Into Its Melanin Regulation And Ecological Niche, Erin C. Carr, Quin Barton, Sarah Grambo, Mitchell Sullivan, Cecile M. Renfro, Alan Kuo, Jasmyn Pangilinan, Anna Lipzen, Keykhosrow Keymanesh, Emily Savage, Kerrie Barry, Igor V. Grigoriev, Wayne R. Riekhof, Steven D. Harris

School of Biological Sciences: Faculty Publications

Black yeasts are polyextremotolerant fungi that contain high amounts of melanin in their cell wall and maintain a primar yeast form. These fungi grow in xeric, nutrient depletes environments which implies that they require highly flexible metabolisms and have been suggested to contain the ability to form lichen-like mutualisms with nearby algae and bacteria. However, the exact ecological niche and interactions between these fungi and their surrounding community are not well understood. We have isolated 2 novel black yeasts from the genus Exophiala that were recovered from dryland biological soil crusts. Despite notable differences in colony and cellular morphology, both …

A Standard Protocol To Report Discrete Stage-Structured Demographic Information, Samuel J. L. Gascoigne, Simon Rolph, Daisy Sankey, Nagalakshmi Nidadavolu, Adrian S. Stell Pičman, Christina M. Hernández, Matthew E. R. Philpott, Aiyla Salam, Connor Bernard, Erola Fenollosa, Young Jun Lee, Jessica Mclean, Shathuki Hetti Achchige Perera, Oliver G. Spacey, Maja Kajin, Anna C. Vinton, C. Ruth Archer, Jean H. Burns, Danielle L. Buss, Hal Caswell, Judy P. Che-Castaldo, Dylan Z. Childs, Pol Capdevila, Aldo Compagnoni, Elizabeth Crone, Thomas H. G. Ezard, Dave Hodgson, Tiffany M. Knight, Owen R. Jones, Eelke Jongejans, Jenni Mcdonald, Brigitte Tenhumberg, Chelsea C. Thomas, Andrew J. Tyre, Satu Ramula, Iain Stott, Raymond L. Tremblay, Phil Wilson, James James Vaupel, Roberto Salguero-Gómez

School of Biological Sciences: Faculty Publications

1. Stage-based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology and conservation science. Accordingly, MPMs now exist for over 3000 species worldwide. These data are being digitised as an ongoing process and periodically released into two large open-access online repositories: the COMPADRE Plant Matrix Database and the COMADRE Animal Matrix Database. During the last decade, data archiving and curation of COMPADRE and COMADRE, and subsequent comparative research, have revealed pronounced variation in how MPMs are parameterized and reported.

2. Here, we summarise current issues related to …

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The Synergistic Response Of Primary Production In Grasslands To Combined Nitrogen And Phosphorus Addition Is Caused By Increased Nutrient Uptake And Retention, Eduardo Vázquez, Elizabeth T. Borer, Miguel N. Bugalho, Maria C. Caldeira, Rebecca L. Mcculley, Anita C. Risch, Eric W. Seabloom, George R. Wheeler, Marie Spohn

School of Biological Sciences: Faculty Publications

Background and aims A synergistic response of aboveground plant biomass production to combined nitrogen (N) and phosphorus (P) addition has been observed in many ecosystems, but the underlying mechanisms and their relative importance are not well known. We aimed at evaluating several mechanisms that could potentially cause the synergistic growth response, such as changes in plant biomass allocation, increased N and P uptake by plants, and enhanced ecosystem nutrient retention.

Methods We studied five grasslands located in Europe and the USA that are subjected to an element addition experiment composed of four treatments: control (no element addition), N addition, …

Ecological Boundaries And Constraints On Viable Eco-Evolutionary Pathways, Kyle E. Coblentz, John P. Delong

School of Biological Sciences: Faculty Publications

Evolutionary dynamics are subject to constraints ranging from limitations on what is physically possible to limitations on the pathways that evolution can take. One set of evolutionary constraints, known as ‘demographic constraints’, constrain what can occur evolutionarily due to the demographic or dynamical consequences of evolution leading to conditions that make populations susceptible to extinction. These demographic constraints can limit the strength of selection or the rates of environmental change populations can experience while remaining extant and the trait values a population can express. Here we further hypothesize that the population demographic and dynamic consequences of evolution also can constrain …

Lessons From Chloroviruses: The Complex And Diverse Roles Of Viruses In Food Webs, John Delong, James L. Van Etten, David Dunigan

School of Biological Sciences: Faculty Publications

Viruses can have large effects on the ecological communities in which they occur. Much of this impact comes from the mortality of host cells, which simultaneously alters microbial community composition and causes the release of matter that can be used by other organisms. However, recent studies indicate that viruses may be even more deeply integrated into the functioning of ecological communities than their effect on nutrient cycling suggests. In particular, chloroviruses, which infect chlorella-like green algae that typically occur as endosymbionts, participate in three types of interactions with other species. Chlororviruses (i) can lure ciliates from a distance, using them …

Examining Whether And How Instructional Coordination Occurs Within Introductory Undergraduate Stem Courses, Brian Couch, Luanna B. Prevost, Marilyne Stains, Blake Whitt, Ariel E. Marcy, Naneh Apkarian, Melissa H. Dancy, Charles Henderson, Estrella Johnson, Jeffrey R. Raker, Brandon J. Yik, Brittnee Earl, Susan E. Shadle, John Skvoretz, John P. Ziker

School of Biological Sciences: Faculty Publications

Instructors’ interactions can foster knowledge sharing around teaching and the use of research-based instructional strategies (RBIS). Coordinated teaching presents an impetus for instructors’ interactions and creates opportunities for instructional improvement but also potentially limits an instructor’s autonomy. In this study, we sought to characterize the extent of coordination present in introductory undergraduate courses and to understand how departments and instructors implement and experience course coordination. We examined survey data from 3,641 chemistry, mathematics, and physics instructors at three institution types and conducted follow-up interviews with a subset of 24 survey respondents to determine what types of coordination existed, what factors …

Longitudinal Variations In Antibody Responses Against Sars-Cov-2 Spike Epitopes Upon Serial Vaccinations, Dicle Yalcin, Sydney J. Bennett, Jared Sheehan, Amber J. Trauth, For Yue Tso, John T. West, Michael E. Hagensee, Alistair J. Ramsay, Charles Wood

School of Biological Sciences: Faculty Publications

The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impacted healthcare, the workforce, and worldwide socioeconomics. Multi-dose mono- or bivalent mRNA vaccine regimens have shown high efficacy in protection against SARSCoV- 2 and its emerging variants with varying degrees of efficacy. Amino acid changes, primarily in the receptor-binding domain (RBD), result in selection for viral infectivity, disease severity, and immune evasion. Therefore, many studies have centered around neutralizing antibodies that target the RBD and their generation achieved through infection or vaccination. Here, we conducted a unique longitudinal study, analyzing the effects of a three-dose mRNA vaccine …

Upregulation Of Cell Surface Glycoproteins In Correlation With Kshv Lana In The Kaposi Sarcoma Tumor Microenvironment, Sara R. Privatt, Owen Ngalamika, Jianshui Zhang, Qinsheng Li, Charles Wood, John T. West

School of Biological Sciences: Faculty Publications

HIV-associated epidemic Kaposi sarcoma (EpKS) remains one of the most prevalent cancers in sub-Saharan Africa despite the widespread uptake of anti-retroviral therapy and HIV-1 suppression. In an effort to define potential therapeutic targets against KS tumors, we analyzed previously published KS bulk tumor transcriptomics to identify cell surface biomarkers. In addition to upregulated gene expression (>6-fold) in the EpKS tumor microenvironment, biomarkers were selected for correlation with KSHV latency-associated nuclear antigen (LANA) expression. The cell surface glycoprotein genes identified were KDR, FLT4, ADAM12, UNC5A, ZP2, and OX40, as well as the endothelial lineage determinants Prox-1 and CD34. Each protein …

Small Rnas >26 Nt In Length Associate With Ago1 And Are Upregulated By Nutrient Deprivation In The Alga Chlamydomonas, Yingshan Li, Eun-Jeong Kim, Adam Voshall, Etsuko Moriyama, Heriberto D. Cerutti

School of Biological Sciences: Faculty Publications

Small RNAs (sRNAs) associate with ARGONAUTE (AGO) proteins forming effector complexes with key roles in gene regulation and defense responses against molecular parasites. In multicellular eukaryotes, extensive duplication and diversification of RNA interference (RNAi) components have resulted in intricate pathways for epigenetic control of gene expression. The unicellular alga Chlamydomonas reinhardtii also has a complex RNAi machinery, including 3 AGOs and 3 DICER-like proteins. However, little is known about the biogenesis and function of most endogenous sRNAs. We demonstrate here that Chlamydomonas contains uncommonly long (>26 nt) sRNAs that associate preferentially with AGO1. Somewhat reminiscent of animal PIWI-interacting RNAs, …

Dwarfism And Gigantism Drive Human-Mediated Extinctions On Islands, Roberto Rozzi, Mark V. Lomolino, Alexandra A.E. Van Der Geer, Daniele Silvestro, S. Kathleen Lyons, Pere Bover, Josep A. Alcover, Ana Benítez-López, Cheng-Hsiu Tsai, Masaki Fujita, Mugino O. Kubo, Janinie Ochoa, Matthew E, Scarborough, Samuel T. Turvey, Alexander Zizka, Jonathan M. Chase

School of Biological Sciences: Faculty Publications

Islands have long been recognized as distinctive evolutionary arenas leading to morphologically divergent species, such as dwarfs and giants. We assessed how body size evolution in island mammals may have exacerbated their vulnerability, as well as how human arrival has contributed to their past and ongoing extinctions, by integrating data on 1231 extant and 350 extinct species from islands and paleo islands worldwide spanning the past 23 million years. We found that the likelihood of extinction and of endangerment are highest in the most extreme island dwarfs and giants. Extinction risk of insular mammals was compounded by the arrival of …

Ecological Boundaries And Constraints On Viable Eco-Evolutionary Pathways, Kyle E. Coblentz, John P. Delong

School of Biological Sciences: Faculty Publications

Evolutionary dynamics are subject to constraints ranging from limitations on what is physically possible to limitations on the pathways that evolution can take. One set of evolutionary constraints, known as ‘demographic constraints’, constrain what can occur evolutionarily due to the demographic or dynamical consequences of evolution leading to conditions that make populations susceptible to extinction. These demographic constraints can limit the strength of selection or the rates of environmental change populations can experience while remaining extant and the trait values a population can express. Here we further hypothesize that the population demographic and dynamic consequences of evolution also can constrain …

How Administration Stakes And Settings Affect Student Behavior And Performance On A Biology Concept Assessment, Crystal Uminski, Joanna K. Hubbard, Brian Couch

School of Biological Sciences: Faculty Publications

Biology instructors use concept assessments in their courses to gauge student understanding of important disciplinary ideas. Instructors can choose to administer concept assessments based on participation (i.e., lower stakes) or the correctness of responses (i.e., higher stakes), and students can complete the assessment in an in-class or out-of-class setting. Different administration conditions may affect how students engage with and perform on concept assessments, thus influencing how instructors should interpret the resulting scores. Building on a validity framework, we collected data from 1578 undergraduate students over 5 years under five different administration conditions. We did not find significant differences in scores …