Digital Commons Network^™

The Pest Kill Rate Of Thirteen Natural Enemies As Aggregate Evaluation Criterion Of Their Biological Control Potential Of Tuta Absoluta, Joop C. Van Lenteren, Alberto Lanzoni, Lia Hemerik, Vanda H.P. Bueno, Johanna G. Bajonero Cuervo, Antonio Biondi, Giovanni Burgio, Francisco J. Calvo, Peter W. De Jong, Silvia N. López, M. Gabriela Luna, Flavio C. Montes, Eliana L. Nieves, Pascal Osa Aigbedion-Atalor, Maria B. Riquelme Virgala, Norma E. Sánchez, Alberto Urbaneja

All Peer-Reviewed Publications

Ecologists study how populations are regulated, while scientists studying biological pest control apply population regulation processes to reduce numbers of harmful organisms: an organism (a natural enemy) is used to reduce the population density of another organism (a pest). Finding an effective biological control agent among the tens to hundreds of natural enemies of a pest is a daunting task. Evaluation criteria help in a first selection to remove clearly ineffective or risky species from the list of candidates. Next, we propose to use an aggregate evaluation criterion, the pest kill rate, to compare the pest population reduction capacity of …

Semiochemical Signatures Associated With Differential Attraction Of Anopheles Gambiae To Human Feet, Maurice O. Omolo, Isaiah O. Ndiege, Ahmed Hassanali

All Peer-Reviewed Publications

Background: Several human-produced volatiles have been reported to mediate the host-seeking process under laboratory conditions, yet no effective lure or repellent has been developed for field application. Previously, we found a gradation of the attractiveness of foot odors of different malaria free individuals to Anopheles gambiae sensu stricto Giles. In this study, foot odor of the individual with the most attractive 'smelly' feet to the An. gambiae was collected, analyzed and attractive blend components identified. Methods: The foot odor of the individual with the most attractive 'smelly' feet to the An. gambiae was trapped on Porapak Q and analyzed by …

In Situ Nitrogen Mineralization And Nutrient Release By Soil Amended With Black Soldier Fly Frass Fertilizer, Dennis Beesigamukama, Benson Mochoge, Nicholas Korir, Changeh J. Ghemoh, Sevgan Subramanian, Chrysantus M. Tanga

All Peer-Reviewed Publications

Although black soldier fly frass fertilizer (BSFFF) is effective on crop performance, information on nitrogen (N) mineralization and nutrient release capacity of soils amended with BSFFF is lacking. This study utilized field incubation experiments to investigate the ammonification, nitrification, microbial populations, and quantities of nutrients released by soils amended with BSFFF and commercial organic fertilizer (SAFI) for a period equivalent to two maize cropping seasons. For the control treatment, no BSFFF or SAFI was added. Results indicated that most of the N in BSFFF amended soils was available in the ammonium form, while soils treated with SAFI had higher nitrate …

Global Population Genetic Structure And Demographic Trajectories Of The Black Soldier Fly, Hermetia Illucens, Cengiz Kaya, Tomas N. Generalovic, Gunilla Ståhls, Martin Hauser, Ana C. Samayoa, Carlos G. Nunes-Silva, Heather Roxburgh, Jens Wohlfahrt, Ebenezer A. Ewusie, Marc Kenis, Yupa Hanboonsong, Jesus Orozco, Nancy Carrejo, Satoshi Nakamura, Laura Gasco, Santos Rojo, Chrysantus M. Tanga, Rudolf Meier, Clint Rhode, Christine J. Picard, Chris D. Jiggins, Florian Leiber, Jeffery K. Tomberlin, Martin Hasselmann, Wolf U. Blanckenhorn, Martin Kapun, Christoph Sandrock

All Peer-Reviewed Publications

Background: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents. Results: We identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data …

Whole Genome Comparisons Reveal Panmixia Among Fall Armyworm (Spodoptera Frugiperda) From Diverse Locations, Katrina A. Schlum, Kurt Lamour, Caroline Placidi De Bortoli, Rahul Banerjee, Robert Meagher, Eliseu Pereira, Maria Gabriela Murua, Gregory A. Sword, Ashley E. Tessnow, Diego Viteri Dillon, Angela M. Linares Ramirez, Komivi S. Akutse, Rebecca Schmidt-Jeffris, Fangneng Huang, Dominic Reisig, Scott J. Emrich, Juan Luis Jurat-Fuentes

All Peer-Reviewed Publications

Background: The fall armyworm (Spodoptera frugiperda (J.E. Smith)) is a highly polyphagous agricultural pest with long-distance migratory behavior threatening food security worldwide. This pest has a host range of > 80 plant species, but two host strains are recognized based on their association with corn (C-strain) or rice and smaller grasses (R-strain). The population genomics of the United States (USA) fall armyworm remains poorly characterized to date despite its agricultural threat. Results: In this study, the population structure and genetic diversity in 55 S. frugiperda samples from Argentina, Brazil, Kenya, Puerto Rico and USA were surveyed to further our understanding of …

A System Dynamics Model For Pests And Natural Enemies Interactions, Bonoukpoè Mawuko Sokame, Henri E.Z. Tonnang, Sevgan Subramanian, Anani Y. Bruce, Thomas Dubois, Sunday Ekesi, Paul André Calatayud

All Peer-Reviewed Publications

Stemborers (Busseola fusca, Sesamia calamistis and Chilo partellus), the fall armyworm (Spodoptera frugiperda) and associated parasitoids constitute an interacting system in maize fields in Kenya. This work aims at developing and evaluating models that represent the evolution of those interactions by applying system thinking and system dynamics approaches with its archetypes [causal loop diagram (CLD), reinforcing (R) and balancing (B)] to analyse the population of these multi-species systems. The software Vensim PLE 8.0.9 was used to implement the models and carry out the simulations of single- and multi-species systems. The results showed that when a single pest species with its …

Promoting Employer Desired Competencies Through A Multiphased "Workgroup" Project, Ashly Smith

International Journal for Business Education

Employers and business leaders have long been advocating for the importance of career readiness skills like critical thinking/problem solving, information literacy, teamwork/collaboration, professionalism/work ethic, and oral/written communication (NACE, 2019; Partnership, 2008). While faculty and students see value in projects that develop these skills, such projects can be some of the most challenging to incorporate effectively into business courses (Chapman et al., 2010; Detmering & Johnson, 2012; Lee et al., 2016; Marks & O’Connor, 2013). This article reports on a multi-phase group project that aims to strengthen a selection of these employer-desired skills while ameliorating student concerns about the research process …

Practice Enterprises In Times Of Distance Learning: The Impact And Consequences Of The Covid-19 Pandemic To The Collaboration Of Practice Enterprises, Theresa Feuchter, Gernot Dreisiebner, Elisabeth Riebenbauer, Ph.D., Michaela Stock

International Journal for Business Education

The aim of this paper is to outline the consequences which arise from the digital transformation of the multidimensional teaching and learning setting of practice enterprises and to discuss how digital collaboration of students can be supported during the COVID-19 pandemic. As an evolutionary moment also in the field of education, one can consider the experiences of COVID-19 as a catalyst for digital transformation and distance learning in education. How digital collaboration can be fostered in times of distance learning is shown by using the example of business simulations such as practice enterprises (PE). While previously this multidimensional teaching and …

Internships As Clinical Rotations In Business: Enhancing Access And Options, Faye W. Gilbert, Jason Harkins, Pankaj Agrrawal, Taylor Ashley

International Journal for Business Education

Internships are high impact practices that offer work experiences and provide advantages for participating undergraduate students and for the talent acquisition efforts of firms. While research consistently documents the benefits of internships as a transformative experience, access and outcomes may vary for students and for underserved populations. Limitations of internships can include lack of access to enough positions as well as inadequate interactions between undergraduate students, firms, and faculty members in business programs. The purpose of this article is to describe an approach to enhancing access to internships on a larger scale with greater variety. Protocols found in clinical rotations …

How Are Agricultural Research Projects Conceiving Innovation? An Assessment Of The European Union Multi-Actor Projects, Samuel Brea Martinez-Collado

Graduate Theses and Dissertations

Horizon research programs are the European Union’s lighthouse for innovation and research concerning the agri-food chain, the management of natural resources, and the bioeconomy. Their innovation strategy approach is one that pursues the practical application of the research via the collaboration of all actors involved. Such strategy is the reflection of a Multi-Actor Approach as their procedure to enhance innovation. This paper presents the main trends and directions 101 Multi-Actor Projects (MAPs) are following on said approach towards innovation. The analysis is based on the use of well-defined “pathways” and “measures” proposed in the Guidelines for Evaluation of Innovation in …

Investigating Effects Of Microenvironmental Stress On Cell Metabolism Using Multiphoton Imaging, Lisa Rebello

Graduate Theses and Dissertations

Resistance to therapy in cancer is a major cause of poor prognosis in patients. Tumor hypoxia plays an active role in mediating treatment resistance and has been linked to metastases and metastatic potential in cancer. Our research focused on three objectives: i) To understand metabolic effects of chronic and intermittent hypoxia in murine breast cancer cells and its affiliation with metastatic potential ii) To identify the metabolic changes associated with radiation therapy in a panel of radiosensitive and radioresistant human head and neck cancer cells and iii) to monitor the changes in cell metabolism associated with gain of treatment resistance. …

Solar Generated Electricity: An Analysis Of What Sectors Are Most Affected By Renewable Portfolio Standards And Related Policies, Logan Knollenberg

Dissertations and Theses

The aim of this thesis is to analyze state-specific Renewable Portfolio Standards (RPS) to understand their design and spillover effect onto non-utility (commercial, residential, industrial) sectors. Past research has overlooked non-utility sectors, often focusing on overall renewable energy growth and electricity generation from a combined end-result perspective. Solar capacity and solar generated electricity data from 5 states are used to establish which non-utility sectors experienced the highest level of solar growth from RPSs and related policies between 2010 and 2019. An explanatory sequential design is utilized, where interrupted time series analyses and exploratory case studies are performed to analyze each …

Triple Oxygen Isotope Constraints On Atmospheric O2 And Biological Productivity During The Mid-Proterozoic, Peng Liu, Jingjin Liu, Aoshaung Ji, Christopher T. Reinhard, Noah J. Planavsky, Dmitri Babikov, Raymond G. Najjar, James F. Kasting

Chemistry Faculty Research and Publications

Reconstructing the history of biological productivity and atmospheric oxygen partial pressure (pO₂) is a fundamental goal of geobiology. Recently, the mass-independent fractionation of oxygen isotopes (O-MIF) has been used as a tool for estimating pO₂ and productivity during the Proterozoic. O-MIF, reported as Δ′¹⁷O, is produced during the formation of ozone and destroyed by isotopic exchange with water by biological and chemical processes. Atmospheric O-MIF can be preserved in the geologic record when pyrite (FeS₂) is oxidized during weathering, and the sulfur is redeposited as sulfate. Here, sedimentary sulfates from …

2d Covalent Organic Frameworks With An Incorporated Manganese Complex For Light Driven Carbon Dioxide Reduction, Denan Wang, Daniel Streater, Yun Peng, Jier Huang

Chemistry Faculty Research and Publications

Covalent organic frameworks (COFs) have emerged as a novel class of crystalline porous photocatalytic materials due to their unique properties such as large surface area, tunable porosity, and rigid structure. In this work, we report the direct incorporation of a manganese CO₂ molecular catalyst (MC) into COFs (Mn−TTA-COF) and the evaluation of its capability as photocatalyst for visible light driven CO₂ reduction to form CO. We found that the photocatalytic activity of Mn−TTA-COF is quite low, which mainly results from the elimination of the CO ligand in the Mn MC upon light illumination, rendering its short duration in …

Library Holiday Hours, Beatriz Varman

TMC Library Newsletter (2015-)

The library will be closed Friday, December 24 - Sunday, January 2 Regular hours resume January 3, 2022

The Roles And Responsibilities Of The Covid-19 Elementary Principal In Relation To Job Descriptions And Utah School Leadership Evaluation Metrics: A Case Study, Sarah R. Nielsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the roles and responsibilities of elementary school principals in relation to how they are evaluated and what is included in their job descriptions during the COVID-19 pandemic. Because of the numerous policies that surround education and the COVID-19 pandemic, this study examined elementary school principals from a single school district in Utah. Seven principals agreed to participate in an interview that asked principals about their day-to-day responsibilities as a principal and how COVID-19 affected those responsibilities. Six principals agreed to participate in a daily reflection on how much time they spent participating …

Enzymatic Synthesis Of Maltodextrin Fatty Acid Esters And Their Emulsion Stabilizing And Microbial Inhibitory Properties, Namhyeon Park

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Food additives have been one of the traditional methods for preserving foods and are still in everyday use for multiple reasons. As the market size of processed foods grows, the use of food additives is increasing. Simultaneously, consumers try to avoid specific food additives or demand less processed foods because of several potential health concerns, suggesting the need for safe food additives.

In this environment, one group of food additives consisting of carbohydrates and fatty acids have received attention because of its nontoxicity and biodegradability with diverse functions. Notably, carbohydrate fatty acid compounds made of sucrose have been approved and …

Proof Positive: Applications Of Chemical Analysis Techniques In Art Forgery Detection, Joseph Fryc

Museum Studies Theses

In response to the subjective nature of older forgery detection techniques, modern forgery detection methods rely heavily on chemical analysis of the materials utilized in a given piece of work in order to make authenticity determinations. Chemical methods of detection at their core provide an objective determination of facts regarding the composition of materials utilized in contested pieces and provide a relative date of production for those materials. In this way, chemical analysis helps service the field of modern forgery detection as a direct compliment to traditional stylistic analysis, by providing extra data on the piece that can often be …

Museums & Environmental Sustainability: Are They Doing Enough?, Alexandra M. Dwyer

Museum Studies Theses

As the world continues to be affected by the rapid rates of climate change, institutions from every sector are transitioning to become more sustainable by reducing or eliminating their harmful habits on the ecosystem. Whether by their own accord or external pressure from current legislative action to cut carbon emissions, institutions are shifting towards a sustainable future. For museums there are additional unique reasons to adopt sustainability into various aspects with their institution. The most influential reason is that museums have a responsibility as community leaders and change makers. However, looming questions remain: Are museums doing enough? Are these cultural …

Creating The Experience: Engaging Millennials In Museums With A Focus On Jewish Millennials And Museums, Sarah G. Drozda

Museum Studies Theses

In this research, I explore two main ideas: The relationship that millennials have with museums and what programming excites them into coming back to the museum. To do this, I did a background review of the motivations and passions of the millennial generation, as well as various programming that have engaged millennials in museums. As someone who is a millennial and passionate about Jewish museums and Jewish engagement, I focused my research on how museums can help to bring Jewish millennials closer to their heritage, culture, and Jewish identity. A good segment of Jewish millennials is not drawn to traditional …

An Investigation Into The Feasibility Of Streamlining Language Sample Analysis Through Computer-Automated Transcription And Scoring, Carly Fox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the study was to investigate the feasibility of streamlining the transcription and scoring portion of language sample analysis (LSA) through computer-automation. LSA is a gold-standard procedure for examining childrens’ language abilities that is underutilized by speech language pathologists due to its time-consuming nature. To decrease the time associated with the process, the accuracy of transcripts produced automatically with Google Cloud Speech and the accuracy of scores generated by a hard-coded scoring function called the Literate Language Use in Narrative Analysis (LLUNA) were evaluated. A collection of narrative transcripts and audio recordings of narrative samples were selected to …

Field Evaluation Of A New Third Generation Push-Pull Technology For Control Of Striga Weed, Stemborers, And Fall Armyworm In Western Kenya, Duncan Cheruiyot, Frank Chidawanyika, Charles A.O. Midega, Jimmy O. Pittchar, John A. Pickett, Zeyaur R. Khan

All Peer-Reviewed Publications

Production of cereal crops in sub-Saharan Africa is threatened by parasitic striga weeds and attack by stemborers and the invasive fall armyworm (FAW), compounded by increasing hot and dry conditions. A climate-smart push-pull technology (PPT) significantly reduces effects of these biotic challenges. To improve further resilience of the system to climate change, more adapted and suitable companion plants were identified and integrated in a new version of PPT, termed 'third generation PPT'. Our study evaluates field performance and farmer opinions of this new version in comparison with the earlier version, climate-smart PPT, and farmers' own practices of growing maize in …

Occurrence, Diversity And Distribution Of Trypanosoma Infections In Cattle Around The Akagera National Park, Rwanda, S. Richard Gashururu, Ndichu Maingi, Samuel M. Githigia, Methode N. Gasana, Peter O. Odhiambo, Dennis O. Getange, Richard Habimana, Giuliano Cecchi, Weining Zhao, James Gashumba, Joel L. Bargul, Daniel K. Masiga

All Peer-Reviewed Publications

Background African Trypanosomiases threaten the life of both humans and animals. Trypanosomes are transmitted by tsetse and other biting flies. In Rwanda, the African Animal Trypanosomiasis (AAT) endemic area is mainly around the tsetse-infested Akagera National Park (NP). The study aimed to identify Trypanosoma species circulating in cattle, their genetic diversity and distribution around the Akagera NP. Methodology A cross-sectional study was carried out in four districts, where 1,037 cattle blood samples were collected. The presence of trypanosomes was determined by microscopy, immunolog-ical rapid test VerY Diag and PCR coupled with High-Resolution Melt (HRM) analysis. A parametric test (ANOVA) was …

Temperature-Dependent Modelling And Spatial Prediction Reveal Suitable Geographical Areas For Deployment Of Two Metarhizium Anisopliae Isolates For Tuta Absoluta Management, Ayaovi Agbessenou, Komivi S. Akutse, Abdullahi A. Yusuf, Sospeter W. Wekesa, Fathiya M. Khamis

All Peer-Reviewed Publications

Tuta absoluta is one of the most devastating pests of Solanaceae crops in Africa. We previously demonstrated the efficacy of Metarhizium anisopliae isolates ICIPE 18, ICIPE 20 and ICIPE 665 against adult T. absoluta. However, adequate strain selection and accurate spatial prediction are fundamental to optimize their efficacy and formulations before field deployment. This study therefore assessed the thermotolerance, conidial yield and virulence (between 15 and 35 °C) of these potent isolates. Over 90% of conidia germinated at 20, 25 and 30 °C while no germination occurred at 15 °C. Growth of the three isolates occurred at all temperatures, but …

Molecular Prevalence And Risk Factors Associated With Tick-Borne Pathogens In Cattle In Western Kenya, Tatenda Chiuya, Jandouwe Villinger, Daniel K. Masiga, Dickens O. Ondifu, Maurice K. Murungi, Lillian Wambua, Armanda D.S. Bastos, Eric M. Fèvre, Laura C. Falzon

All Peer-Reviewed Publications

Background: Tick-borne pathogens (TBPs) are of global importance, especially in sub-Saharan Africa where they represent a major constraint to livestock production. Their association with human disease is also increasingly recognized, signalling their zoonotic importance. It is therefore crucial to investigate TBPs prevalence in livestock populations and the factors associated with their presence. We set out to identify TBPs present in cattle and to determine associated risk factors in western Kenya, where smallholder livestock production is important for subsistence and market-driven income. Results: Tick-borne pathogen infections in blood samples collected from cattle at livestock markets and slaughterhouses between May 2017 and …

Satellite-Based Modelling Of Potential Tsetse (Glossina Pallidipes) Breeding And Foraging Sites Using Teneral And Non-Teneral Fly Occurrence Data, Stella Gachoki, Thomas Groen, Anton Vrieling, Michael Okal, Andrew Skidmore, Daniel Masiga

All Peer-Reviewed Publications

Background: African trypanosomiasis, which is mainly transmitted by tsetse flies (Glossina spp.), is a threat to public health and a significant hindrance to animal production. Tools that can reduce tsetse densities and interrupt disease transmission exist, but their large-scale deployment is limited by high implementation costs. This is in part limited by the absence of knowledge of breeding sites and dispersal data, and tools that can predict these in the absence of ground-truthing. Methods: In Kenya, tsetse collections were carried out in 261 randomized points within Shimba Hills National Reserve (SHNR) and villages up to 5 km from the reserve …

Global Overview Of Locusts As Food, Feed And Other Uses, J. P. Egonyu, S. Subramanian, C. M. Tanga, T. Dubois, S. Ekesi, S. Kelemu

All Peer-Reviewed Publications

The term 'locusts' refers to insect species which can aggregate into migratory swarms that cause wide-scale destruction of crops and pasture, causing significant effect to food security. This review assesses the potential of harnessing locust swarms for beneficial uses. Among 21 known locusts, ~10 species have been traditionally consumed by humans or fed to animals for millennia in 65 countries. Their nutritional composition is comparable or superior to that of conventional meat. However, insecticide residues, microbial contaminants and allergens may compromise their safety. Some countries have developed regulations on edible insects, locusts inclusive. Safe and efficient harvest of locusts could …

Distribution And Mating Type Characterization Of Chickpea Blight (Didymella Rabiei (Kov.) V. Arx) In Ethiopia, Gezahegne Getaneh, Tadele Tefera, Fikre Lemessa, Seid Ahmed, Jandouwe Villinger

All Peer-Reviewed Publications

We have assessed the distribution and mating type of chickpea blight (Didymella rabiei (Kov.) v. Arx) from a total of 350 and 272 fields in major chickpea (Cicer arietinum L.) growing areas of Ethiopia for two consecutive cropping seasons 2017 and 2018, respectively. The prevalence of D. rabiei was 20 % for the year 2017 and 7% for 2018. Severity range of 2−9 and incidence of 10–100 % were recorded for both seasons in only 7–20 % of the assed fields. Field prevalence of 2017 and 2018 seasons were significantly different (df = 31; p < 0.001 and df = 31; p < 0.001, respectively). Similarly, the disease prevalence of both seasons was significantly different (df = 31; p < 0.001). The disease prevalence ratio frequency was highly deviated from (1:1) for both seasons (X2 = 213.62 p= <0.001; X2 = 144.36 p = 0.01). Genomic DNA of Representative samples were extracted from single spore culture and Mating type 1 (MAT1-1) specific primer SP21, Mating type 2 (MAT1-2) specific primer Tail 5, and a flanking region-specific primer Com1 assay were multiplexed in a single PCR reaction to determine the occurrence of D. rabiei mating type in Ethiopia. Out of 156 samples, only 15 samples were positive to MAT1-1 (∼10 %) with the ratio of 9:1. MAT 1−2 type was the most dominant and possibly the asexual reproduction of D. rabiei is the major type in Ethiopia. The result is important for Ascochyta blight management in breeding strategy.

The Dilemma Of Guinea Grass (Megathyrsus Maximus): A Valued Pasture Grass And A Highly Invasive Species, Aaron C. Rhodes, Robert M. Plowes, John A. Goolsby, John F. Gaskin, Boaz Musyoka, Paul André Calatayud, Massimo Cristofaro, Eric D. Grahmann, Dino J. Martins, Lawrence E. Gilbert

All Peer-Reviewed Publications

On a global scale, invasive grasses threaten biodiversity and ecosystem function. Nevertheless, the importation of forage grasses is a significant economic force driven by globalization. Pastureland and rangeland are of critical economic and ecological importance, but novel grass species may lead to invasion. Recognizing that economically important species can also be ecologically damaging creates a contentious debate for land managers, policymakers, and ecologists alike. Many Afrotropical perennial grass species have been intentionally introduced pantropically given their high forage production and resistance to stress. However, these traits may also confer competitive ability, increasing the possibility of unintended escape and invasion. Further, …

Mating Behaviour, Mate Choice And Female Resistance In The Bean Flower Thrips (Megalurothrips Sjostedti), Adeyemi O. Akinyemi, Sevgan Subramanian, David K. Mfuti, Tom W. Pope, Amanuel Tamiru, William D.J. Kirk

All Peer-Reviewed Publications

Many species of thrips (Thysanoptera) in the family Thripidae form mating aggregations, but the adaptive significance of these aggregations and the extent of male and female mate choice is poorly understood. We studied the mating behaviour of the bean flower thrips Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), which forms male aggregations and occurs across sub-Saharan Africa. We tested whether males choose mates by female age or mating status. No-choice mating bioassays with one male and one female were used to simulate the way males usually encounter only one female at a time in aggregations in the field. Virgin females violently resisted …