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Sex And Nest Type Influence Avian Blood Parasite Prevalence In A High-Elevation Bird Community, Marina D. Rodriguez, Paul F. Doherty, Antoinette J. Piaggio, Kathryn P. Huyvaert

United States Department of Agriculture Wildlife Services: Staff Publications

Background: The prevalence of avian haemosporidian parasites and the factors influencing infection in the Colorado Rocky Mountains are largely unknown. With climate change expected to promote the expansion of vector and avian blood parasite distributions, baseline knowledge and continued monitoring of the prevalence and diversity of these parasites is needed.

Methods: Using an occupancy modeling framework, we conducted a survey of haemosporidian parasite species infecting an avian community in the Colorado Rocky Mountains in order to estimate the prevalence and diversity of blood parasites and to investigate species-level and individual-level characteristics that may influence infection.

Results: We estimated the prevalence …

Potential Use For Serosurveillance Of Feral Swine To Map Risk For Anthrax Exposure, Texas, Usa, Rachel M. Maison, Courtney F. Pierce, Izabela K. Ragan, Vienna R. Brown, Michael J. Bodenchuk, Richard A. Bowen, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

Anthrax is a disease of concern in many mammals, including humans. Management primarily consists of prevention through vaccination and tracking clinical-level observations because environmental isolation is laborious and bacterial distribution across large geographic areas diffi cult to confi rm. Feral swine (Sus scrofa) are an invasive species with an extensive range in the southern United States that rarely succumbs to anthrax. We present evidence that feral swine might serve as biosentinels based on comparative seroprevalence in swine from historically defi ned anthrax-endemic and non–anthraxendemic regions of Texas. Overall seropositivity was 43.7% (n = 478), and logistic regression revealed county endemicity …

Publisher Correction: The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control (Bmc Biology, (2021), 19, 1, (41), 10.1186/S12915-021-00975-9), Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Following publication of the original article [1], it was reported that the article copyright was incorrect. The correct copyright statement is: © This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2021. The original article [1] has been corrected.

Genetic Fingerprinting And Aflatoxin Production Of Aspergillus Section Flavi Associated With Groundnut In Eastern Ethiopia, Abdi Mohammed, Paola C. Faustinelli, Alemayehu Chala, Mashilla Dejene, Chemeda Fininsa, Amare Ayalew, Chris O. Ojiewo, David A. Hoisington, Victor S. Sobolev, Jaime Martínez-Castillo, Renee S. Arias

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Aspergillus species cause aflatoxin contamination in groundnut kernels, being a health threat in agricultural products and leading to commodity rejection by domestic and international markets. Presence of Aspergillus flavus and A. parasiticus colonizing groundnut in eastern Ethiopia, as well as presence of aflatoxins have been reported, though in this region, no genetic studies have been done of these species in relation to their aflatoxin production. Results: In this study, 145 Aspergillus isolates obtained from groundnut kernels in eastern Ethiopia were genetically fingerprinted using 23 Insertion/Deletion (InDel) markers within the aflatoxin-biosynthesis gene cluster (ABC), identifying 133 ABC genotypes. Eighty-four isolates …

Greenhouse Gas Emissions From Two Contrasting Beef Systems From Birth To Slaughter In Eastern Nebraska, Levi J. Mcphillips

Department of Animal Science: Dissertations, Theses, and Student Research

Over the last 15 years, the increase in land use for corn and soybean has come at the expense of acres of grasslands and perennial forages employed in conventional beef-production systems. Implementing alternative cow-calf production systems into existing cropping systems may be a solution for reduced land availability and reducing total greenhouse gas emissions (GHG). Therefore, GHG from a conventional (CONV) pasture-based cattle production system with cows wintered on corn residue and summer grazing of brome pasture were compared to partial-confinement system (ALT) with cows and calves in a drylot during the summer and grazing cover crops and corn residue …

Small Grain Cereal Cover Crops For Late Fall Or Early Spring Grazing, Kallie J. Calus

Department of Animal Science: Dissertations, Theses, and Student Research

Beef cattle operations are confronted with early spring and late fall forage deficiencies. Producers in integrated crop and livestock systems can fill forage gaps using cover crops as a forage source in between cash crops.

A five-year study evaluating forage production, growing calf performance and economics of grazing an oats cover crop planted after corn silage (CS) and high moisture corn (HMC) corn harvests was conducted. The economic analysis accounted for costs of establishing and grazing the oats and the value of calf gain to determine fall grazing system profitability. Steers had greater average daily gain grazing oats after CS …

Management Of Late Summer Planted Annual Forages For Grazing And The Impacts Of Novel Sweet Bran Plus Products On Performance And Carcass Characteristics Of Beef Finishing Steers, Devin Anthony Jakub

Department of Animal Science: Dissertations, Theses, and Student Research

Two separate grazing studies were conducted to evaluate: 1) the effects of rapeseed inclusion into late summer planted oats on the performance of growing steers during late fall and winter (Exp. 1) and 2) the effects of forage allocation on forage utilization and performance of steers grazing a late summer planted oat-rapeseed mix (Exp. 2). Variation in the corn wet milling process can result in negative effects on animal performance, nonetheless, there remains interest in further exploration and refinement of corn wet milling byproducts to achieve optimal byproduct compositions and cattle performance. Thus, another experiment was conducted to evaluate the …

Impact Of Wood-Sourced Biochar On Carbon And Nitrogen Capture In Beef Feedlot Systems, Jessica L. Sperber

Department of Animal Science: Dissertations, Theses, and Student Research

A feedlot growing and finishing experiment evaluated the effect of including pine-sourced biochar at 0.8 (growing) and 1.0% (finishing) of dietary DM on steer performance, carcass characteristics, and greenhouse gas (GHG) production (Exp 1). Two nutrient mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading unprocessed red cedar biochar on the feedlot pen surface on manure nutrient capture and cattle performance (Exp 2). In Exp. 1, the inclusion of biochar in the growing diet did not impact steer performance. The inclusion of biochar in the finishing diet significantly reduced intake and gain, resulting …

Utilizing Online Resources To Enhance Distribution Of Competitive Animal Evaluation Knowledge And Benefits, Brooke L. Parrish

Department of Animal Science: Dissertations, Theses, and Student Research

In recent years, the shift toward online education has revealed new challenges for learners to retain information, and for educators to find new and engaging ways to present content. This mixed methods, action research study explores the need and creation of online resources for competitive horse judging through surveys and pilot groups. The study was broken into four cycles. The first was an adult learner analysis survey, distributed through email Listservs and extension social media pages, to aid in answering the research questions: what expert horse judging instructors indicate their students should be learning, and what resources they need. Based …

Evaluation Of Cattle Management For Systems With Limited Perennial Pasture, Morgan Grabau

Department of Animal Science: Dissertations, Theses, and Student Research

Due to the conversion of perennial pasture and hay land to cropland in the western corn belt region, alternative methods of cow/calf management are being used to decrease reliance on perennial forages. These include grazing corn residue and feeding cow/calf pairs in confinement. Previous research has shown that limit-feeding a diet of low-quality forage and energy-dense co-products to cows in confinement is cost-effective. However, this strategy may limit the intake of the young calf and thus their performance. A study was conducted to evaluate the impacts of two alternative calf management strategies when pairs are in confinement, early weaning or …

Feeding A New Corn Milling Coproduct To Lactating Dairy Cattle: Examination Of Whole Animal Energy And Nitrogen Balance, Addison Lee Carroll

Department of Animal Science: Dissertations, Theses, and Student Research

New coproducts are continually developed in the ethanol production industry. With that, the new product originates from the dry milling process which is unlike the traditional process as nitrogenous based particles are concentrated from the residual fiber by sieving post fermentation. Although high protein coproducts have been available since the mid 2000’s. These new products must be evaluated for chemical composition so that they can be accurately described in feed libraries that are used in commercial ration formulation software. While chemical composition provides us an initial and useful description of a feed product, in vivo nitrogen and energy balance studies …

Host Genetics And Phenotype Associations Within The Bovine Rumen Microbiome, Waseem Abbas

Department of Animal Science: Dissertations, Theses, and Student Research

Rumen microbes have a symbiotic relationship with the host where the host provides a suitable environment and microbial fermentation fulfill nearly 70% of the energy needs of the host. Rumen microbes play a central role in host performance and health. To date, most rumen microbiome studies have focused on the influence of diet on microbial species composition. In addition to dietary factors, studies have suggested that host genetic markers could influence the colonization of gastrointestinal microbiota. However, our understanding of the host-microbiome interaction and how host phenotype is influenced by the rumen microbiome is limited. This dissertation demonstrates: (1) host …

Application Of Biochar As Beneficial Additive In Concrete, Temirlan Barissov

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Biochar is a high-carbon solid material produced via thermal decomposition of organic biomass in a low-oxygen environment. Characterized with high water retention properties and high alkalinity, biochar is generally used for soil amendment and fertilization purposes. This study is intended to explore the feasibility of using biochar as a beneficial additive of the most used manmade material, concrete. Literature review revealed several studies where biochar was successfully implemented as an additive in concrete. The beneficial influence of biochar on the mechanical characteristics of concrete is based on nucleation and densification effects. However, the internal microstructure, porosity and chemical composition of …

Modeling Watershed Sensitivity To Climate Change In Systems Affected By Discharge Of Mine Tailings, Johnette C. Shockley

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

For more than a century, a large volume of gold-mining tailings was deposited in Whitewood Creek and the Belle Fourche River, tributaries to the Cheyenne River in western South Dakota. Much of it still remains, and field and historical evidence indicates continued remobilization of tailings-containing alluvium in these bedrock-dominated channels. Both long-term, natural fluctuations in climate and anthropogenically driven changes can impact regional precipitation, temperature, hydrologic patterns, and ecosystem functions. Such changes have the potential to affect both the transport and distribution of arsenic-laden sediments and mechanical erosion that can undermine the stability of channel-bed and overbank material.

This study …

How Do Genetic Relatedness And Spatial Proximity Shape African Swine Fever Infections In Wild Boar?, Tomasz Podgórski, Kim M. Pepin, Anna Radko, Angelika Podbielska, Magdalena Łyjak, Grzegorz Woźniakowski, Tomasz Borowik

United States Department of Agriculture Wildlife Services: Staff Publications

The importance of social and spatial structuring of wildlife populations for disease spread, though widely recognized, is still poorly understood in many host-pathogen systems. In particular, system-specific kin relationships among hosts can create contact heterogeneities and differential disease transmission rates. Here, we investigate how distance-dependent infection risk is influenced by genetic relatedness in a novel host-pathogen system: wild boar (Sus scrofa) and African swine fever (ASF).We hypothesized that infection risk would correlate positively with proximity and relatedness to ASF-infected individuals but expected those relationships to weaken with the distance between individuals due to decay in contact rates and …

Seeding Rate Effects On Forage Mass And Vegetation Dynamics Of Cool-Season Grass Sod Interseeded With Sorghum-Sudangrass, John A. Guretzky, D. D. Redfearn

Department of Agronomy and Horticulture: Faculty Publications

Interseeding annual warm-season grasses into perennial cool-season grasses has the potential to increase summer forage mass and nutritive value. Knowledge of how seeding rate affects annual warm-season grass establishment, forage mass, and vegetation dynamics remains limited. From 2016–2017, we conducted a field experiment evaluating the effects of seeding rates on sorghum-sudangrass (Sorghum bicolor x S. bicolor var. sudanense) density and forage mass and on the frequency of occurrence of plant species in cool-season grass sod in Lincoln, NE. The experiment had a completely randomized design consisting of six replicates of four seeding rates [0, 14, 28, and 35 …

2019ncovr – A Comprehensive Genomic Resource For Sars-Cov-2 Variant Surveillance And Covid-19 Control, Guoquing Lu, Etsuko N. Moriyama

School of Biological Sciences: Faculty Publications

No abstract provided.

Amilorides Inhibit Sars-Cov-2 Replication In Vitro By Targeting Rna Structures, Martina Zafferani, Christina Haddad, Le Luo, Jesse Davila-Calderon, Liang-Yuan Chiu, Christian Shema Mugisha, Adeline G. Monaghan, Andrew A. Kennedy, Joseph D. Yesselman, Robert J. Gifford, Andrew W. Tai, Sebla B. Kutluay, Mei-Ling Li, Gary Brewer, Blanton S. Tolbert, Amanda E. Hargrove

Department of Chemistry: Faculty Publications

The SARS-CoV-2 pandemic, and the likelihood of future coronavirus pandemics, emphasized the urgent need for development of novel antivirals. Small-molecule chemical probes offer both to reveal aspects of virus replication and to serve as leads for antiviral therapeutic development. Here, we report on the identification of amiloride-based small molecules that potently inhibit OC43 and SARS-CoV-2 replication through targeting of conserved structured elements within the viral 5′-end. Nuclear magnetic resonance–based structural studies revealed specific amiloride interactions with stem loops containing bulge like structures and were predicted to be strongly bound by the lead amilorides in retrospective docking studies. Amilorides represent the …

Biomarkers For Resistance To Porcine Circovirus 2 Associated Disease, Daniel Constantin Ciobanu, Lianna Rayne Walker, Taylor Benjamin Engle, Hiep Vu

Department of Animal Science: Faculty Publications

The present disclosure provides compositions and methods for increasing resistance to PCV2 infection in pigs. The increased resistance may be the result of siRNA or genetic modification through CRISPR or a vectored virus targeting SNPs that are resistant to PCV2 infection.

Considerations And Best Practices In Animal Science 16s Ribosomal Rna Gene Sequencing Microbiome Studies, Margaret D. Weinroth, Aeriel D. Belk, Chris Dean, Noelle Noyes, Dana K. Dittoe, Michael J. Rothrock Jr, Steven C. Ricke, Phillip R. Myer, Madison T. Henniger, Gustavo A. Ramírez, Brian B. Oakley, Katie Lynn Summers, Asha M. Miles, Taylor B. Ault-Seay, Zhongtang Yu, Jessica L. Metcalf, James E. Wells

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Microbiome studies in animal science using 16S rRNA gene sequencing have become increasingly common in recent years as sequencing costs continue to fall and bioinformatic tools become more powerful and user-friendly. The combination of molecular biology, microbiology, microbial ecology, computer science, and bioinformatics—in addition to the traditional considerations when conducting an animal science study—makes microbiome studies sometimes intimidating due to the intersection of different fields. The objective of this review is to serve as a jumping-off point for those animal scientists less familiar with 16S rRNA gene sequencing and analyses and to bring up common issues and concerns that arise …

Stabilin Receptors Clear Lps And Control Systemic Inflammation, Fatima Cabral, Mustafa Al-Rahem, John Skaggs, Thushara A. Thomas, Naresh Kumar, Qian Wu, Paolo Fadda, Lianbo Yu, John M. Robinson, Jonghan Kim, Ekta Pandey, Xinghui Sun, Wael N. Jarjour, Murugesan V.S. Rajaram, Edward N. Harris, Latha P. Ganesan

Department of Biochemistry: Faculty Publications

Lipopolysaccharides (LPSs) cause lethal endotoxemia if not rapidly cleared from blood circulation. Liver sinusoidal endothelial cells (LSEC) systemically clear LPS by unknown mechanisms. We discovered that LPS clearance through LSEC involves endocytosis and lysosomal inactivation via Stabilin-1 and 2 (Stab1 and Stab2) but does not involve TLR4. Cytokine production was inversely related to clearance/endocytosis of LPS by LSEC. When exposed to LPS, Stabilin double knockout mice (Stab DK) and Stab1 KO, but not Stab2 KO, showed significantly enhanced systemic inflammatory cytokine production and early death compared with WT mice. Stab1 KO is not significantly different from Stab DK in circulatory …

Twenty-Four-Month Longitudinal Study Suggests Little To No Horizontal Gene Transfer In Situ Between Third-Generation Cephalosporin-Resistant Salmonella And Third-Generation Cephalosporin-Resistant Escherichia Coli In A Beef Cattle Feedyard, John W. Schmidt, Sarah A. Murray, Aaron M. Dickey, Tommy L. Wheeler, Dayna M. Harhay, Terrance M. Arthur

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Third-generation cephalosporins (3GCs) are preferred treatments for serious human Salmonella enterica infections. Beef cattle are suspected to contribute to human 3GC-resistant Salmonella infections. Commensal 3GC-resistant Escherichia coli are thought to act as reservoirs of 3GC resistance because these strains are isolated more frequently than are 3GC-resistant Salmonella strains at beef cattle feedyards. During each of 24 consecutive months, four samples of pen surface material were obtained from five pens (N = 480) at a Nebraska feedyard to determine to the contribution of 3GC-resistant E. coli to the occurrence of 3GC-resistant Salmonella. Illumina whole genome sequencing was performed, and …

Ticks (Acari: Ixodidae) Parasitizing Migrating And Local Breeding Birds In Finland, Jani J. Sormunen, Tero Klemola, Eero J. Vesterinen

Harold W. Manter Laboratory of Parasitology: Library Materials

Ticks are globally renowned vectors for numerous zoonoses, and birds have been identified as important hosts for several species of hard ticks (Acari: Ixodidae) and tick-borne pathogens. Many European bird species overwinter in Africa and Western Asia, consequently migrating back to breeding grounds in Europe in the spring. During these spring migrations, birds may transport exotic tick species (and associated pathogens) to areas outside their typical distribution ranges. In Finland, very few studies have been conducted regarding ticks parasitizing migrating or local birds, and existing data are outdated, likely not reflecting the current situation. Consequently, in 2018, we asked volunteer …

Signaling In Training, Megan Paul

Umbrella Summaries

What is signaling?

In a learning environment, signaling refers to cues that direct learners’ attention to specific instructional content or that emphasize how the content is organized (van Gog, 2014). Signals can be verbal (oral or written) or visual (static or dynamic images or graphics). More commonly studied examples include:

signals in written materials: underlining, italics, bold, highlighting, outlines, headings, overviews, and summaries

signals in visual materials: arrows, circles, flashing, color coding, spotlighting (graying out some content), zooming in on key content, and gestures of pedagogical agents

When signals are used only in written text (i.e., without accompanying visuals), they …

Evidence Of Myomir Regulation Of The Pentose Phosphate Pathway During Mechanical Load-Induced Hypertrophy, Taylor Valentino, Vandre C. Figueiredo, C. Brooks Mobley, John J. Mccarthy, Ivan Jose Vechetti Jr

Department of Nutrition and Health Sciences: Faculty Publications

Many of the molecular and cellular mechanisms discovered to regulate skeletal muscle hypertrophy were first identified using the rodent synergist ablation model. This model reveals the intrinsic capability and necessary pathways of skeletal muscle growth in response to mechanical overload (MOV). Reminiscent of the rapid cellular growth observed with cancer, we hypothesized that in response to MOV, skeletal muscle would undergo metabolic programming to sustain increased demands to support hypertrophy. To test this hypothesis, we analyzed the gene expression of specific metabolic pathways taken from transcriptomic microarray data of a MOV time course. We found an upregulation of genes involved …

A Chickpea Genetic Variation Map Based On The Sequencing Of 3,366 Genomes, Rajeev K. Varshney, Manish Roorkiwal, Shuai Sun, Prasad Bajaj, Annapurna Chitikineni, Mahendar Thudi, Narendra P. Singh, Xiao Du, Hari D. Upadhyaya, Diego Jarquin

Department of Agronomy and Horticulture: Faculty Publications

Zero hunger and good health could be realized by 2030 through effective conservation, characterization and utilization of germplasm resources1 . So far, few chickpea (Cicerarietinum) germplasm accessions have been characterized at the genome sequence level2 . Here we present a detailed map of variation in 3,171 cultivated and 195 wild accessions to provide publicly available resources for chickpea genomics research and breeding. We constructed a chickpea pan-genome to describe genomic diversity across cultivated chickpea and its wild progenitor accessions. A divergence tree using genes present in around 80% of individuals in one species allowed us to estimate the divergence of …

Mt10-Cvb3 Vaccine Virus Protects Against Cvb4 Infection By Inducing Cross-Reactive, Antigen-Specific Immune Responses, Ninaad Lasrado, Rajkumar Arumugam, Mahima T. Rasquinha, Meghna Sur, David Steffen, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Group B coxsackieviruses (CVB) containing six serotypes, B1–B6, affect various organs, and multiple serotypes can induce similar diseases such as myocarditis and pancreatitis. Yet, no vaccines are currently available to prevent these infections. Translationally, the derivation of vaccines that offer protection against multiple serotypes is highly desired. In that direction, we recently reported the generation of an attenuated strain of CVB3, termed Mt10, which completely protects against both myocarditis and pancreatitis induced by the homologous wild-type CVB3 strain. Here, we report that the Mt10 vaccine can induce cross-protection against multiple CVB serotypes as demonstrated with CVB4. We note that the …

Risk Based Simulations Of Sporeformers Population Throughout The Dairy Production And Processing Chain: Evaluating On-Farm Interventions In Nebraska Dairy Farms, Rhaisa A. Crespo Ramírez

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Sporeformer bacteria are ubiquitous in the farm environment. These bacteria produce enzymes that negatively affect the quality of dairy products representing a problem for the dairy industry. Two major issues associated with high levels of sporeformers in raw milk are shelf-life reduction of fluid milk and market limitations for milk powder. Specific attention has been given to the contamination of milk powders with sporeformers due to their ability to survive pasteurization and milk powder processing conditions. Hence, the control of sporeformers is crucial to benefit the whole dairy industry. Researchers have suggested that certain management practices could decrease sporeformers in …

Protein Kinase A And 59 Amp-Activated Protein Kinase Signaling Pathways Exert Opposite Effects On Induction Of Autophagy In Luteal Cells, Emilia Przygrodzka, Corrine F. Monaco, Michele R. Plewes, Guojuan Li, Jennifer R. Wood, Andrea Cupp, John S. Davis

Department of Animal Science: Faculty Publications

In the absence of pregnancy the ovarian corpus luteum undergoes regression, a process characterized by decreased production of progesterone and structural luteolysis involving apoptosis. Autophagy has been observed in the corpus luteum during luteal regression. Autophagy is a self-degradative process important for balancing sources of cellular energy at critical times in development and in response to nutrient stress, but it can also lead to apoptosis. Mechanistic target of rapamycin (MTOR) and 5′ AMP-activated protein kinase (AMPK), key players in autophagy, are known to inhibit or activate autophagy, respectively. Here, we analyzed the signaling pathways regulating the initiation of autophagy in …

The Dynamics Of Dominance: Open Questions, Challenges And Solutions, Eli D. Strauss, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Although social hierarchies are recognized as dynamic systems, they are typically treated as static entities for practical reasons. Here, we ask what we can learn from a dynamical view of dominance, and provide a research agenda for the next decades. We identify five broad questions at the individual, dyadic and group levels, exploring the causes and consequences of individual changes in rank, the dynamics underlying dyadic dominance relationships, and the origins and impacts of social instability. Although challenges remain, we propose avenues for overcoming them. We suggest distinguishing between different types of social mobility to provide conceptual clarity about hierarchy …