Digital Commons Network^™

Genomic Resources In Plant Breeding For Sustainable Agriculture, Mahendar Thudi, Rajeev K. Varshney, James C. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Climate change during the last 40 years has had a serious impact on agriculture and threatens global food and nutritional security. From over half a million plant species, cereals and legumes are the most important for food and nutritional security. Although systematic plant breeding has a relatively short history, con- ventional breeding coupled with advances in technology and crop management strategies has increased crop yields by 56 % globally between 1965− 85, referred to as the Green Revolution. Nevertheless, increased demand for food, feed, fiber, and fuel necessitates the need to break existing yield barriers in many crop plants. In …

Development Of Mping-Based Activation Tags For Crop Insertional Mutagenesis, Alexander Johnson, Edward Mcassey, Stephanie Diaz, Jacod Reagin, Priscilla S. Redd, Daymond R. Parrilla, Hanh Nguyen, Adrian Stec, Lauren A.L. Mcdaniel, Thomas E. Clemente, Robert M. Stupar, Wayne A. Parrott, C. Nathan Hancock

Department of Agronomy and Horticulture: Faculty Publications

Modern plant breeding increasingly relies on genomic information to guide crop im- provement. Although some genes are characterized, additional tools are needed to effectively identify and characterize genes associated with crop traits. To address this need, the mPing element from rice was modified to serve as an activation tag to in- duce expression of nearby genes. Embedding promoter sequences in mPing resulted in a decrease in overall transposition rate; however, this effect was negated by using a hyperactive version of mPing called mmPing20. Transgenic soybean events carrying mPing-based activation tags and the appropriate transposase expression cassettes showed evidence of transposition. …

Responses Of Soil Surface Greenhouse Gas Emissions To Nitrogen And Sulfur Fertilizer Rates To Brassica Carinata Grown As A Bio-Jet Fuel, Dwarika Bhattarai, Gandura O. Abagandura, Thandiwe Nleya, Sandeep Kumar

Department of Agronomy and Horticulture: Faculty Publications

Carinata (Brassica carinata A. Braun), a non-food oilseed crop and an alternative bio-jet fuel feedstock, has received attention for its potential as a low-input option for production in the semi-arid region of the Northern Great Plains of the United States. Research addressing the impacts of nitrogen (N) and sulfur (S) fertilizers on soils and greenhouse gas (GHG; CO2, N2O, and CH4) emissions from carinata production are limited. Thus, objective of this study was to evaluate the impact of different rates of N and S fertilizers applied to carinata on soil properties and GHG emissions. Field experiments were conducted in 2017 …

Household Smoke-Exposure Risks Associated With Cooking Fuels And Cooking Places In Tanzania: A Cross-Sectional Analysis Of Demographic And Health Survey Data, Mazbahul G. Ahamad, Fahian Tanin, Nawaraji Shrestha

Department of Agronomy and Horticulture: Faculty Publications

Household smoke-exposure risk (SER) can be defined through the assessment of cooking fuels (smoke and no smoke-producing) and cooking places (indoor and outdoor) related information, which represent different levels of household air pollution. This study aimed to explore the prevalence and geographical variations in smoke-exposure risks (SERs) associated with indoor and outdoor cooking practices and use of smoke-producing and non-smoke-producing cooking fuels in Tanzania. We further investigated the social and spatial features associated with household SERs. We defined an indicator variable, the household SER, using country-level, cross-sectional data on cooking fuels and cooking places obtained from the 2015–2016 Tanzania Demographic …

Officially Confirmed Covid-19 And Unreported Covid-19–Like Illness Death Counts: An Assessment Of Reporting Discrepancy In Bangladesh, Mazbahul G. Ahamad, Fahian Tanin, Byomkesh Talukder, Monir Ahmed

Department of Agronomy and Horticulture: Faculty Publications

Reporting discrepancies between officially confirmed COVID-19 death counts and unreported COVID- 19–like illness (CLI) death counts have been evident across the world, including Bangladesh. Publicly available data were used to explore the differences between confirmed COVID-19 death counts and deaths with possible COVID-19 symptoms between March 2, 2020 and August 22, 2020. Unreported CLI death counts totaled more than half of the confirmed COVID-19 death counts during the study period. However, the reporting authority did not consider CLI deaths, which might produce incomplete and unreliable COVID-19 data and respective mortality rates. All deaths with possible COVID-19 symptoms need to be …

Soil Erosion Modelling: A Global Review And Statistical Analysis, Pasquale Borrelli, Panos Panagos, Dinesh Panday, 64 More Co-Authors

Department of Agronomy and Horticulture: Faculty Publications

To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published between 1994 and 2017.We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named ‘Global Applications of Soil Erosion …

Potential Amendments For Improving Productivity Of Low Carbon Semiarid Soil, Bijesh Maharjan, Dinesh Panday, Humberto Blanco-Canqui, Maysoon M. Mikha

Department of Agronomy and Horticulture: Faculty Publications

Applying soil amendments with high C content can potentially improve soil properties and increase crop yields. The objective of this 3-yr field study was to evaluate the effects of organic amendments on soil organic C (SOC), chemical properties, crop nutrient uptake, and crop yields in a low C sandy loam soil near Scottsbluff, NE. The field was planted to dry bean (Phaseolus vulgaris L.) in 2017, maize (Zea mays L.) in 2018, and sugar beet (Beta vulgaris L.) in 2019. Char at 22.3, 44.6, 66.9, 89.2, and 133.8 Mg ha^–1; biochar at 5.6 and 11.2 …

Loss Of Comt Activity Reduces Lateral Root Formation And Alters The Response To Water Limitation In Sorghum Brown Midrib (Bmr) 12 Mutant, Manny Saluja, Feiyu Zhu, Hongfeng Yu, Harkamal Walia, Scott E. Sattler

Department of Agronomy and Horticulture: Faculty Publications

Lignin is a key target for modifying lignocellulosic biomass for efficient biofuel production. Brown midrib 12 (bmr12) encodes the sorghum caffeic acid O-methyltransferase (COMT) and is one of the key enzymes in monolignol biosynthesis. Loss of function mutations in COMT reduces syringyl (S) lignin subunits and improves biofuel conversion rate. Although lignin plays an important role in maintaining cell wall integrity of xylem vessels, physiological and molecular consequences due to loss of COMT on root growth and adaptation to water deficit remain unexplored.

We addressed this gap by evaluating the root morphology, anatomy and transcriptome of bmr12 mutant. The mutant …

Improving Publicly Available Corn Nitrogen Rate Recommendation Tools With Soil And Weather Measurements, Curtis J. Ransom, Newell R. Kitchen, John E. Sawyer, James J. Camberato, Paul R. Carter, Richard Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A.M. Laboski, D. Brenton Myers, Emerson D. Nafziger, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Improving corn (Zea mays L.) N fertilizer rate recommendation tools is necessary for improving farmers’ profits and minimizing N pollution. Research has repeatedly shown that weather and soil factors influence available N and crop N need. Adjusting available corn N recommendation tools with soil and weather measurements could improve farmers’ ability to manage N. The aim of this research was to improve publicly available N recommendation tools with site-specific soil and weather measurements. Information from49 site-years ofNresponse trials in theU.S. Midwest was used to evaluate 21 rate recommendation tools for a single (at-planting) and split (at-planting + sidedress) N …

Adaptation And Forage Productivity Of Cool-Season Grasses In The Central Usa, Kenneth P. Vogel, Robert B. Mitchell

Department of Agronomy and Horticulture: Faculty Publications

Cool-season grass species (18) and cultivars (85) were evaluated for use in seeded grasslands in the tallgrass prairie and shortgrass steppe ecoregions of the central United States at the test locations of Ithaca and Sidney, NE, respectively. Both native and introduced grasses were evaluated in sward trails. Significant differences existed among species and cultivars for all traits evaluated except for in vitro dry matter digestibility (IVDMD) among cultivars within species at Sidney. The grasses that had the best establishment, persistence, and forage yields in the Ithaca trial were introduced wheatgrass (Thinopyrum) and bromegrass (Bromus) species. At …

Sister Species Diverge In Modality-Specific Courtship Signal Form And Function, Eileen Hebets, Mitch Bern, Rowan H. Mcginley, Andy Roberts, Arik Kershenbaum, James Starrett, Jason E. Bond

School of Biological Sciences: Faculty Publications

Understanding the relative importance of different sources of selection (e.g., the environment, social/sexual selection) on the divergence or convergence of reproductive communication can shed light on the origin, maintenance, or even disappearance of species boundaries. Using a multistep approach, we tested the hypothesis that two presumed sister species of wolf spider with overlapping ranges and microhabitat use, yet differing degrees of sexual dimorphism, have diverged in their reliance on modality- specific courtship signaling. We predicted that male Schizocosa crassipalpata (no ornamentation) rely predominantly on diet-dependent vibratory signaling for mating success. In contrast, we predicted that male S. bilineata (black foreleg …

Body Mass-Related Changes In Mammal Community Assembly Patterns During The Late Quaternary Of North America, Silvia Pineda-Munoz, Advait M. Jukar, Anikó B. Toth, Danielle Fraser, Andrew Du, W. Andrew Barr, Kathryn L. Amatangelo, Meghan A. Balk, Anna K. Behrensmeyer, Jessica Blois, Matt Davis, Jussi T. Eronen, Nicholas J. Gotelli, Cindy Looy, Joshua H. Miller, Alexandria B. Shupinski, Laura C. Soul, Amelia Villaseñor, Scott Wing, S. Kathleen Lyons

School of Biological Sciences: Faculty Publications

The late Quaternary of North America was marked by prominent ecological changes, including the end-Pleistocene megafaunal extinction, the spread of human settlements and the rise of agriculture. Here we examine the mechanistic reasons for temporal changes in mammal species association and body size during this time period. Building upon the co-occurrence results from Lyons et al. (2016) – wherein each species pair was classified as spatially aggregated, segregated or random – we examined body mass differences (BMD) between each species pair for each association type and time period (Late Pleistocene: 40 000 ¹⁴C–11 700 ¹⁴C ybp, Holocene: 11 …

Associations Between Statin/Omega3 Usage And Mri-Based Radiomics Signatures In Prostate Cancer, Yu Shi, Ethan Wahle, Qian Du, Luke Krajewski, Xiaoying Liang, Sumin Zhou, Chi Zhang, Michael J. Baine, D Zheng

School of Biological Sciences: Faculty Publications

Prostate cancer is the most common noncutaneous cancer and the second leading cause of cancer deaths among American men. Statins and omega-3 are two medications recently found to correlate with prostate cancer risk and aggressiveness, but the observed associations are complex and controversial. We therefore explore the novel application of radiomics in studying statin and omega-3 usage in prostate cancer patients. On MRIs of 91 prostate cancer patients, two regions of interest (ROIs), the whole prostate and the peripheral region of the prostate, were manually segmented. From each ROI, 944 radiomic features were extracted after field bias correction and normalization. …

The Potential Use Of Radiomics With Pre-Radiation Therapy Mr Imaging In Predicting Risk Of Pseudoprogression In Glioblastoma Patients, Michael J. Baine, Justin Burr, Qian Du, Chi Zhang, Xiaoying Liang, Luke Krajewski, Laura Zima, Gerard Rux, Chi Zhang, Dandan Zheng

School of Biological Sciences: Faculty Publications

Glioblastoma (GBM) is the most common adult glioma. Differentiating post-treatment effects such as pseudoprogression from true progression is paramount for treatment. Radiomics has been shown to predict overall survival and MGMT (methylguanine-DNA methyltransferase) pro- moter status in those with GBM. A potential application of radiomics is predicting pseudoprogression on pre-radiotherapy (RT) scans for patients with GBM. A retrospective review was performed with radiomic data analyzed using pre-RT MRI scans. Pseudoprogression was defined as post-treatment findings on imaging that resolved with steroids or spontaneously on subsequent imaging. Of the 72 patients identified for the study, 35 were able to be assessed …

Sterol Biosynthesis In Four Green Algae: A Bioinformatic Analysis Of The Ergosterol Versus Phytosterol Decision Point, Adam Voshall, Nakeirah T.M. Christie, Suzanne L. Rose, Maya Khasin, James L. Van Etten, Jennifer E. Markham, Wayne R. Riekhof, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Animals and fungi produce cholesterol and ergosterol, respectively, while plants produce the phytosterols stigmasterol, campesterol, and bsitosterol in various combinations. The recent sequencing of many algal genomes allows the detailed reconstruction of the sterol metabolic pathways. Here, we characterized sterol synthesis in two sequenced Chlorella spp., the free-living C. sorokiniana, and symbiotic C. variabilis NC64A. Chlamydomonas reinhardtii was included as an internal control and Coccomyxa subellipsoidea as a plant-like outlier. We found that ergosterol was the major sterol produced by Chlorella spp. and C. reinhardtii, while C. subellipsoidea produced the three phytosterols found in plants. In silico analysis …

Temperature But Not Ocean Acidification Affects Energy Metabolism And Enzyme Activities In The Blue Mussel, Mytilus Edulis, Omera B. Matoo, Gisela Lannig, Christian Bock, Inna M. Sokolova

School of Biological Sciences: Faculty Publications

1. In mosaic marine habitats, such as intertidal zones, ocean acidification (OA) is exacerbated by high variability of pH, temperature, and biological CO₂ production. The nonlinear interactions among these drivers can be context-specific and their effect on organisms in these habitats remains largely unknown, warranting further investigation.

2. We were particularly interested in Mytilus edulis (the blue mussel) from intertidal zones of the Gulf of Maine (GOM), USA, for this study. GOM is a hot spot of global climate change (average sea surface temperature (SST) increasing by >0.2°C/year) with >60% decline in mussel population over the past 40 years. …

Pollinator Assemblage And Pollen Load Differences On Sympatric Diploid And Tetraploid Cytotypes Of The Desert-Dominant Larrea Tridentata, Robert G. Laport, Robert L. Minckley, Diana Pilson

School of Biological Sciences: Faculty Publications

PREMISE: Whole-genome duplication (polyploidy) is an important force shaping flowering-plant evolution. Ploidy-specific plant–pollinator interactions represent important community-level biotic interactions that can lead to nonrandom mating and the persistence of mixed-ploidy populations.

METHODS: At a naturally occurring diploid–tetraploid contact zone of the autopolyploid desert shrub Larrea tridentata, we combined flower phenology analyses, collections of bees on plants of known cytotype, and flow cytometry analyses of bee-collected pollen loads to investigate whether (1) diploid and tetraploid plants have unique bee pollinator assemblages, (2) bee taxa exhibit ploidy-specific visitation and pollen collection biases, and (3) specialist and generalist bee taxa …

Our Past Creates Our Present: A Brief Overview Of Racism And Colonialism In Western Paleontology, Pedro M. Monarrez, Joshua B. Zimmt, Annaka M. Clement, William Gearty, John J. Jacisin Iii, Kelsey M. Jenkins, Kristopher Mm. Kusnerik, Carmi Milagros Thompson, Ashley W. Poust, Selina V. Robson, Judith A. Sclafani, Kelsey T. Stilson, Shamindri D. Tennakoon

School of Biological Sciences: Faculty Publications

As practitioners of a historical science, paleontologists and geoscientists are well versed in the idea that the ability to understand and to anticipate the future relies upon our collective knowledge of the past. Despite this understanding, the fundamental role that the history of paleontology and the geosciences plays in shaping the structure and culture of our disciplines is seldom recognized and therefore not acted upon sufficiently. Here, we present a brief review of the history of paleontology and geology in Western countries, with a particular focus on North America since the 1800s. Western paleontology and geology are intertwined with systematic …

Co-Targeting Strategy For Precise, Scarless Gene Editing With Crispr/Cas9 And Donor Ssodns In Chlamydomonas, Soujanya Akella, Xinrong Ma, Romana Bacova, Zachary P. Harmer, Martina Kolackova, Xiaoxue Wen, David A. Wright, Martin H. Spalding, Donald P. Weeks, Heriberto Cerutti

School of Biological Sciences: Faculty Publications

Programmable site-specific nucleases, such as the clustered regularly interspaced short palindromic repeat (CRISPR)/ CRISPR-associated protein 9 (Cas9) ribonucleoproteins (RNPs), have allowed creation of valuable knockout mutations and targeted gene modifications in Chlamydomonas (Chlamydomonas reinhardtii).

However, in walled strains, present methods for editing genes lacking a selectable phenotype involve co-transfection of RNPs and exogenous doublestranded DNA (dsDNA) encoding a selectable marker gene. Repair of the dsDNA breaks induced by the RNPs is usually accompanied by genomic insertion of exogenous dsDNA fragments, hindering the recovery of precise, scarless mutations in target genes of interest. Here, we tested whether co-targeting two …

Bringing Disciplines And People Together To Characterize The Plastic And Genetic Responses Of Molluscs To Environmental Change, Omera B. Matoo, Maurine Neiman

School of Biological Sciences: Faculty Publications

Molluscs are remarkably diverse and are found across nearly all ecosystems, meaning that members of this ancient animal phylum provide a powerful means to study genomic-phenotype connections in a climate change framework. Recent advances in genomic sequencing technologies and genome assembly approaches finally allow the relatively cheap and tractable assembly of high-quality mollusc genome resources. After a brief review of these issues and advances, we use a case-study approach to provide some concrete examples of phenotypic plasticity and genomic adaptation in molluscs in response to environmental factors expected to be influenced by climate change. Our goal is to use molluscs …

Opposing Community Assembly Patterns For Dominant And Nondominant Plant Species In Herbaceous Ecosystems Globally, Carlos Alberto Arnillas, Elizabeth T. Borer, Eric W. Seabloom, Juan Alberti, Selene Baez, Jonathan D. Bakker, Elizabeth H. Boughton, Yvonne M. Buckley, Miguel Nuno Bugalho, Ian Donohue, John Dwyer, Jennifer Firn, Riley Gridzak, Nicole Hagenah, Yann Hautier, Aveliina Helm, Anke Jentsch, Johannes M. H. Knops, Kimberly J. Komatsu, Lauri Laanisto, Ramesh Laungani, Rebecca Mcculley, Joslin L. Moore, John W. Morgan, Pablo Luis Peri, Sally A. Power, Jodi Price, Mahesh Sankaran, Brandon Schamp, Karina Speziale, Rachel Standish, Risto Virtanen, Marc W. Cadotte

School of Biological Sciences: Faculty Publications

Biotic and abiotic factors interact with dominant plants—the locally most frequent or with the largest coverage—and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead may ameliorate environmental stressors that usually limit nondominants. Hence, the nature of interactions among nondominant species could be modified by dominant species. Furthermore, these differences could translate into a disparity in the phylogenetic …

A Functional Genomic Screen In Saccharomyces Cerevisiae Reveals Divergent Mechanisms Of Resistance To Different Alkylphosphocholine Chemotherapeutic Agents, Jaquelin M. Garcia, Michael J. Schwabe, Dennis R. Voelker, Wayne R. Riekhof

School of Biological Sciences: Faculty Publications

The alkylphosphocholine (APC) class of antineoplastic and antiprotozoal drugs, such as edelfosine and miltefosine, are structural mimics of lyso-phosphatidylcholine (lyso-PC), and are inhibitory to the yeast Saccharomyces cerevisiae at low micromolar concentrations. Cytotoxic effects related to inhibition of phospholipid synthesis, induction of an unfolded protein response, inhibition of oxidative phosphorylation, and disruption of lipid rafts have been attributed to members of this drug class, however, the molecular mechanisms of action of these drugs remain incompletely understood. Cytostatic and cytotoxic effects of the APCs exhibit variability with regard to chemical structure, leading to differences in effectiveness against different organisms or cell …

Unique Structure And Positive Selection Promote The Rapid Divergence Of Drosophila Y Chromosomes, Ching-Ho Chang, Lauren E. Gregory, Kathleen E. Gordon, Colin D. Meiklejohn, Amanda M. Larracuente

School of Biological Sciences: Faculty Publications

Y chromosomes across diverse species convergently evolve a gene-poor, heterochromatic organization enriched for duplicated genes, LTR retrotransposons, and satellite DNA. Sexual antagonism and a loss of recombination play major roles in the degeneration of young Y chromosomes. However, the processes shaping the evolution of mature, already degenerated Y chromosomes are less well-understood. Because Y chromosomes evolve rapidly, comparisons between closely related species are particularly useful. We generated de novo long-read assemblies complemented with cytological validation to reveal Y chromosome organization in three closely related species of the Drosophila simulans complex, which diverged only 250,000 years ago and share >98% sequence …

Targeted Manipulation Of Abundant And Rare Taxa In The Daphnia Magna Microbiota With Antibiotics Impacts Host Fitness Differentially, Reilly O. Cooper, Janna M. Vavra, Clayton E. Cressler

School of Biological Sciences: Faculty Publications

Host-associated microbes contribute to host fitness, but it is unclear whether these contributions are from rare keystone taxa, numerically abundant taxa, or interactions among community members. Experimental perturbation of the microbiota can highlight functionally important taxa; however, this approach is primarily applied in systems with complex communities where the perturbation affects hundreds of taxa, making it difficult to pinpoint contributions of key community members. Here, we use the ecological model organism Daphnia magna to examine the importance of rare and abundant taxa by perturbing its relatively simple microbiota with targeted antibiotics. We used sublethal antibiotic doses to target either rare …

Within- And Trans-Generational Environmental Adaptation To Climate Change: Perspectives And New Challenges, Naim M. Bautista, Amélie Crespel

School of Biological Sciences: Faculty Publications

The current and projected impacts of climate change are shaped by unprecedented rates of change in environmental conditions. These changes likely mismatch the existing coping capacities of organisms within-generations and impose challenges for population resilience across generations. To better understand the impacts of projected scenarios of climate change on organismal fitness and population maintenance, it is crucial to consider and integrate the proximate sources of variability of plastic and adaptive responses to environmental change in future empirical approaches. Here we explore the implications of considering: (a) the variability in different time-scale events of climate change; (b) the variability in plastic …

A Consensus‑Based Ensemble Approach To Improve Transcriptome Assembly, Adam Voshall, Sairam Behera, Xiangjun Li, Xiao‑Hong Yu, Kushagra Kapil, Jitender S. Deogun, John Shanklin, Edgar B. Cahoon, Etsuko N. Moriyama

School of Biological Sciences: Faculty Publications

Background: Systems-level analyses, such as differential gene expression analysis, co-expression analysis, and metabolic pathway reconstruction, depend on the accuracy of the transcriptome. Multiple tools exist to perform transcriptome assembly from RNAseq data. However, assembling high quality transcriptomes is still not a trivial problem. This is especially the case for non-model organisms where adequate reference genomes are often not available. Different methods produce different transcriptome models and there is no easy way to determine which are more accurate. Furthermore, having alternative-splicing events exacerbates such difficult assembly problems. While benchmarking transcriptome assemblies is critical, this is also not trivial due to the …

Genbio-Maps As A Case Study To Understand And Address The Effects Of Test-Taking Motivation In Low-Stakes Program Assessments, Crystal Uminski, Brian A. Couch

School of Biological Sciences: Faculty Publications

The General Biology–Measuring Achievement and Progression in Science (GenBio-MAPS) assessment measures student understanding of the Vision and Change core concepts at the beginning, middle, and end of undergraduate biology degree programs. Assessment coordinators typically administer this instrument as a low-stakes assignment for which students receive participation credit. While these conditions can elicit high participation rates, it remains unclear how to best measure and account for potential variation in the amount of effort students give to the assessment. To better understand student test-taking motivation, we analyzed GenBio-MAPS data from more than 8000 students at 20 institutions. While the majority of students …

Interactions With Soil Fungi Alter Density Dependence And Neighborhood Effects In A Locally Abundant Dipterocarp Species, R. Max Segnitz, Sabrina E. Russo, Kabir G. Peay

School of Biological Sciences: Faculty Publications

Seedling recruitment can be strongly affected by the composition of nearby plant species. At the neighborhood scale (on the order of tens of meters), adult conspecifics can modify soil chemistry and the presence of host microbes (pathogens and mutualists) across their combined canopy area or rooting zones. At local or small spatial scales (on the order of one to few meters), conspecific seed or seedling density can influence the strength of intraspecific light and resource competition and also modify the density-dependent spread of natural enemies such as pathogens or invertebrate predators. Intrinsic correlation between proximity to adult conspecifics (i.e., recruitment …

Sex Role Similarity And Sexual Selection Predict Male And Female Song Elaboration And Dimorphism In Fairy-Wrens, Karan J. Odom, Kristal E. Cain, Michelle L. Hall, Naomi E. Langmore, Raoul A. Mulder, Sonia Kleindorfer, Jordan Karubian, Lyanne Brouwer, Emma I. Greig, Christine Evans, Allison E. Johnson, Kimberley K.-A. Meyers, Marcelo Araya-Salas, Michael S. Webster, Erik D. Enbody, John Anthony Jones, Jenélle L. Dowling, Ana V. Leitão

School of Biological Sciences: Faculty Publications

Historically, bird song complexity was thought to evolve primarily through sexual selection on males; yet, in many species, both sexes sing and selection pressure on both sexes may be broader. Previous research suggests competition for mates and resources during short, synchronous breeding seasons leads to more elaborate male songs at high, temperate latitudes. Furthermore, we expect male–female song structure and elaboration to be more similar at lower, tropical latitudes, where longer breeding seasons and year-round territoriality yield similar social selection pressures in both sexes. However, studies seldom take both types of selective pressures and sexes into account. We examined song …

Testing The Strength And Direction Of Selection On Vocal Frequency Using Metabolic Scaling Theory, Clinton D. Francis, Matthew R. Wilkins

School of Biological Sciences: Faculty Publications

A major challenge for studies assessing drivers of phenotypic divergence is the statistical comparison of taxa with unique, often unknown, evolutionary histories, and for which there are no clear expected trait values. Because many traits are fundamentally constrained by energy availability, we suggest that trait values predicted by scaling theories such as the metabolic theory of ecology (MTE) can provide baseline expectations. Here, we introduce a metabolic scaling-based approach to test theory involving the direction and magnitude of ecological and sexual selection, using vocal frequency as an example target of selection. First, we demonstrate that MTE predicts the relationship between …