Biology Commons^™

How Demographic Processes Shape Animal Social Networks, Daizaburo Shizuka, Allison E. Johnson

School of Biological Sciences: Faculty Publications

Invited review

Demographic processes play a key role in shaping the patterns of social relations among individuals in a population. Social network analysis is a powerful quantitative tool for assessing the social structure formed by associations between individuals. However, demographic processes are rarely accounted for in such analyses. Here, we summarize how the structure of animal social networks is shaped by the joint effects of social behavior and turnover of individuals and suggest how a deeper understanding of these processes can open new, exciting avenues for research. Death or dispersal can have the direct effect of removing an individual and …

Evolutionary Origin And Genetic Diversity Of Ring‐Necked Pheasants In The Upper Midwest United States, Hernán Vázquez-Miranda, Magdalena Jean Olson, Robert M. Zink

School of Biological Sciences: Faculty Publications

We compared mitochondrial cytochrome b sequences of ring‐necked pheasants (Phasianus colchicus) from Midwestern United States (SD and NE, USA) to a molecular phylogeographic hypothesis of pheasants in the native Eurasian range to understand which subspecies are represented by wild and captive released birds. We found that these birds represent 2 Eurasian lineages, which we refer to generally as northern Eurasian (Colchicus group) and eastern China (Torquatus group). These mitochondrial DNA lineages occur in different frequencies in the wild, with the latter being 3 times more common. This suggests that 1) the eastern China lineage is either …

A Role For Triglyceride Lipase Brummer In The Regulation Of Sex Differences In Drosophila Fat Storage And Breakdown, Lianna W. Wat, Chien Chao, Rachael Bartlett, Justin L. Buchanan, Jason W. Millington, Hui Ju Chih, Zahid S. Chowdhury, Puja Biswas, Vivian Huang, Leah J. Shin, Lin Chuan Wang, Marie-Pierre L. Gauthier, Maria C. Barone, Kristi L. Montooth, Michael A. Welte, Elizabeth J. Rideout

School of Biological Sciences: Faculty Publications

Triglycerides are the major form of stored fat in all animals. One important determinant of whole-body fat storage is whether an animal is male or female. Here, we use Drosophila, an established model for studies on triglyceride metabolism, to gain insight into the genes and physiological mechanisms that contribute to sex differences in fat storage. Our analysis of triglyceride storage and breakdown in both sexes identified a role for triglyceride lipase brummer (bmm) in the regulation of sex differences in triglyceride homeostasis. Normally, male flies have higher levels of bmm mRNA both under normal culture conditions and …

Trade-Offs Between Morphology And Thermal Niches Mediate Adaptation In Response To Competing Selective Pressures, Stella F. Uiterwaal, Ian T. Lagerstrom, Thomas M. Luhring, Miranda E. Salsbery, John P. Delong

School of Biological Sciences: Faculty Publications

The effects of climate change—such as increased temperature variability and novel predators—rarely happen in isolation, but it is unclear how organisms cope with mul- tiple stressors simultaneously. To explore this, we grew replicate Paramecium caudatum populations in either constant or variable temperatures and exposed half to predation. We then fit thermal performance curves (TPCs) of intrinsic growth rate (r_max) for each replicate population (N = 12) across seven temperatures (10°C–38°C). TPCs of P. caudatum exposed to both temperature variability and predation re- sponded only to one or the other (but not both), resulting in unpredictable outcomes. …

Radiomics-Based Outcome Prediction For Pancreatic Cancer Following Stereotactic Body Radiotherapy, Elsa Parr, Qian Du, Chi Zhang, Chi Lin, Ahsan Kamal, Josiah Mcalister, Xiaoying Liang, Kyle Bavitz, Gerard Rux, Michael Hollingsworth, Michael Baine, Dandan Zheng

School of Biological Sciences: Faculty Publications

(1) Background: Radiomics use high-throughput mining of medical imaging data to extract unique information and predict tumor behavior. Currently available clinical prediction models poorly predict treatment outcomes in pancreatic adenocarcinoma. Therefore, we used radiomic features of primary pancreatic tumors to develop outcome prediction models and compared them to traditional clinical models. (2) Methods: We extracted and analyzed radiomic data from pre-radiation contrast-enhanced CTs of 74 pancreatic cancer patients undergoing stereotactic body radiotherapy. A panel of over 800 radiomic features was screened to create overall survival and local-regional recurrence prediction models, which were compared to clinical prediction models and models combining …

Extreme Offspring Ornamentation In American Coots Is Favored By Selection Within Families, Not Benefits To Conspecific Brood Parasites, Bruce E. Lyon, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within …

Mitochondrial Localization Of Dictyostelium Discoideum Dutpase Mediated By Its N‑Terminus, Catherine P. Chia, Noriko Inoguchi, Kyle C. Varon, Bradley M. Barholomai, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

Objective: The nuclear and mitochondrial genomes of Dictyostelium discoideum, a unicellular eukaryote, have relatively high A+T-contents of 77.5% and 72.65%, respectively. To begin to investigate how the pyrimidine biosynthetic pathway fulfills the demand for dTTP, we determined the catalytic properties and structure of the key enzyme deoxyuridine triphosphate nucleotidohydrolase (dUTPase) that hydrolyzes dUTP to dUMP, the precursor of dTTP. Results: The annotated genome of D. discoideum identifies a gene encoding a polypeptide containing the five conserved motifs of homotrimeric dUTPases. Recombinant proteins, comprised of either full-length or core polypeptides with all conserved motifs but lacking residues 1-37 of the …

Local Control Of Resource Allocation Is Sufficient To Model Optimal Dynamics In Syntrophic Systems, Glenn Ledder, Sabrina E. Russo, Erik B. Muller, Angela Peace, Roger M. Nisbet

School of Biological Sciences: Faculty Publications

Syntrophic systems are common in nature and include forms of obligate mutualisms in which each participating organism or component of an organism obtains from the other an essential nutrient or metabolic product that it cannot provide for itself. Models of how these complementary resources are allocated between partners often assume optimal behavior, but whether mechanisms enabling global control exist in syntrophic systems, and what form they might take, is unknown. Recognizing that growth of plant organs that supply complementary resources, like roots and shoots, can occur autonomously, we present a theory of plant growth in which rootshoot allocation is determined …

Predator-Dependent Functional Responses Alter The Coexistence And Indirect Effects Among Prey That Share A Predator, Kyle E. Coblentz, John P. Delong

School of Biological Sciences: Faculty Publications

Predator functional responses describe predator feeding rates as a function of prey abundance and are central to pred-ator–prey theory. Despite ample evidence that functional responses also depend on predator abundance, theory incor-porating predator-dependent functional responses has focused almost exclusively on specialist predator–prey pairs or linear food chains. This leaves a large gap in our knowledge as many predators feed on multiple prey, and in so doing, generate indirect effects among prey that can alter their coexistence. Here we investigate how predator-dependent functional responses in a one predator–two prey model alter the coexistence among prey and their net effects on one …

Host Relationships And Geographic Distribution Of Species Of Blanchard, 1848 (Onchoproteocephalidea, Onchobothriidae) In Elasmobranchs: A Metadata Analysis, Francisco Zaragoza-Tapia, Griselda Pulido-Flores, Scott L. Gardner, Scott Monks

Scott L. Gardner Publications

Species of Acanthobothrium have been documented as parasites of the spiral intestine of elasmobranchs. Results of a metadata analysis indicate that 114 species of elasmobranchs have been reported as hosts of 200 species of Acanthobothrium. The metadata analysis revealed that 3.7% of species of sharks and 14.9% of species of rays that have been reported as hosts to date; some species are parasitized by more than one species of Acanthobothrium. This work provides a Category designation, as proposed by Ghoshroy and Caira (2001), for each species of Acanthobothrium. These Category designations are a tool to facilitate comparisons …

Obituary: Sydney Anderson (1927–2018), Scott Lyell Gardner, Robert M. Timm, Nancy Olds, Hugh H. Genoways

Scott L. Gardner Publications

On August 12, 2018, the American Society of Mammalogists (ASM) lost one of its giants of the latter half of the 20th century when Sydney Anderson quietly passed away at his home in Birmingham, Alabama, at the age of 91. “Syd,” to his many friends and colleagues, was born on January 11, 1927 in Topeka, Kansas, to Robert Grant and Evelyn Fern (Hunt) Anderson.

Anderson began his professional career at the University of Kansas, where for four years (1955–1959) he served as Assistant Curator in charge of mammals in the Museum of Natural History, and Instructor in the Department of …

A Self-Marker-Like Protein Governs Hemocyte Allorecognition In Halocynthia Roretzi, Masaki Ema, Taizo Okada, Miki Takahashi, Masato Uchiyama, Hideo Kubo, Hideaki Moriyama, Hitoshi Miyakawa, Midori Matsumoto

School of Biological Sciences: Faculty Publications

Background: Self-incompatibility, fusion/non-fusion reactions, and contact reactions (CRs) have all been identified as allorecognition phenomena in ascidians. CR is a reaction characteristic of the hemocytes of Halocynthia roretzi, whereby they release phenol oxidase (PO) upon contact with non-self hemocytes. Thus, these cells may represent a primitive form of the vertebrate immune system. In the present study, we focused on the CR of H. roretzi hemocytes and sought to identify self-marker proteins that distinguish between self and non-self cells.

Results: We initially generated a CR-inducing monoclonal antibody against the complete hemocyte membraneprotein complement (mAb11B16B10). This antibody was identified based on the …

Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith

School of Biological Sciences: Faculty Publications

The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ¹³C) and nitrogen …

Phenotypically Plastic Responses To Predation Risk Are Temperature Dependent, Thomas M. Luhring, Janna M. Vavra, Clayton E. Cressler, John Delong

School of Biological Sciences: Faculty Publications

Predicting how organisms respond to climate change requires that we understand the temperature dependence of fitness in relevant ecological contexts (e.g., with or without predation risk). Predation risk often induces changes to life history traits that are themselves temperature dependent. We explore how perceived predation risk and temperature interact to determine fitness (indicated by the intrinsic rate of increase, r) through changes to its underlying components (net reproductive rate, generation time, and survival) in Daphnia magna. We exposed Daphnia to predation cues from dragonfly naiads early, late, or throughout their ontogeny. Predation risk increased r differentially across temperatures …

Green Club After School Program Curriculum, Megan Willburn

Honors Program: Expanded Learning Clubs

Green Club is an after school program which encourages students to develop environmental empathy, passions for environmental sustainability, and knowledge about the workings of environmental systems.

Reorganization Of Surviving Mammal Communities After The End-Pleistocene Megafaunal Extinction, Anikó B. Tóth, S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis, Andrew Du, Jussi T. Eronen, J. Tyler Faith, Danielle Fraser, Nicholas J. Gotelli, Gary R. Graves, Advait M. Jukar, Joshua H. Miller, Silvia Pineda-Munoz, Laura C. Soul, Amelia Villaseñor, John Alroy

School of Biological Sciences: Faculty Publications

Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end- Pleistocene megafaunal extinction in North America.We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on cooccurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, …

“What Will I Experience In My College Stem Courses?” An Investigation Of Student Predictions About Instructional Practices In Introductory Courses, Clara L. Meaders, Emma S. Toth, A. K. Lane, J. Kenny Shuman, Brian A. Couch, Marilyne Stains, Mackenzie R. Stetzer, Erin Vinson, Michelle K. Smith

School of Biological Sciences: Faculty Publications

The instructional practices used in introductory college courses often differ dramatically from those used in high school courses, and dissatisfaction with these practices is cited by students as a prominent reason for leaving science, technology, engineering, and mathematics (STEM) majors. To better characterize the transition to college course work, we investigated the extent to which incoming expectations of course activities differ based on student demographic characteristics, as well as how these expectations align with what students will experience. We surveyed more than 1500 undergraduate students in large introductory STEM courses at three research-intensive institutions during the first week of classes …

Investigating How Faculty Social Networks And Peer Influence Relate To Knowledge And Use Of Evidence-Based Teaching Practices, A. K. Lane, John Skvoretz, J. P. Ziker, Brian A. Couch, B. Earl, J. E. Lewis, J. D. Mcalpin, L. B. Prevost, S. E. Shadle, Marilyn Stains

School of Biological Sciences: Faculty Publications

Background: Calls for science education reform have been made for decades in the USA. The recent call to produce one million new science, technology, engineering, and math (STEM) graduates over 10 years highlights the need to employ evidence-based instructional practices (EBIPs) in undergraduate STEM classes to create engaging and effective learning environments. EBIPs are teaching strategies that have been empirically demonstrated to positively impact student learning, attitudes, and achievement in STEM disciplines. However, the mechanisms and processes by which faculty learn about and choose to implement EBIPs remain unclear. To explore this problem area, we used social network analysis …

Metabolism Underlies Physiological Homeostasis In Drosophila, Omera B. Matoo, Cole R. Julick, Kristi Montooth

School of Biological Sciences: Faculty Publications

Organismal physiology emerges from metabolic pathways and subcellular structures like the mitochondria that can vary across development and among individuals. Here, we tested whether genetic variation at one level of physiology can be buffered at higher levels of biological organization during development by the inherent capacity for homeostasis in physiological systems. We found that the fundamental scaling relationship between mass and metabolic rate, as well as the oxidative capacity per mitochondria, changed significantly across development in the fruit fly Drosophila. However, mitochondrial respiration rate was maintained at similar levels across development. Furthermore, larvae clustered into two types—those that switched to …

Opportunities For Behavioral Rescue Under Rapid Environmental Change, Samuel B. Fey, David A. Vasseur, Karla Alujević, Kristy J. Kroeker, Michael L. Logan, Mary I. O'Connor, Volker H.W. Rudolf, John Delong, Scott Peacor, Rebecca L. Selden, A Sih, Susana Clusella‐Trullas

School of Biological Sciences: Faculty Publications

Laboratory measurements of physiological and demographic tolerances are important in understanding the impact of climate change on species diversity; however, it has been recognized that forecasts based solely on these laboratory estimates overestimate risk by omitting the capacity for species to utilize microclimatic variation via behavioral adjustments in activity patterns or habitat choice. The complex, and often context‐dependent nature, of microclimate utilization has been an impediment to the advancement of general predictive models. Here, we overcome this impediment and estimate the potential impact of warming on the fitness of ectotherms using a benefit/cost trade‐off derived from the simple and broadly …

Life History Traits And Functional Processes Generate Multiple Pathways To Ecological Stability, John P. Delong, Torrance C. Hanley, Jean P. Gibert, Linda M. Puth, David M. Post

School of Biological Sciences: Faculty Publications

Stability contributes to the persistence of ecological communities, yet the interactions among different stabilizing forces are poorly understood. We assembled mesocosms with an algal resource and one to eight different clones of the consumer Daphnia ambigua and tracked algal and Daphnia abundances through time. We then fitted coupled ordinary differential equations (ODEs) to the consumer–resource time series. We show that variation in different components of stability (local stability and the magnitude of population fluctuations) across mesocosms arises through variation in life history traits and the functional processes represented by ODE model parameters. Local stability was enhanced by increased algal growth …

Morphological Changes In American Kestrels (Falco Sparverius) At Continental Migration Sites, Teresa E. Ely, Christopher W. Briggs, Shawn E. Hawks, Gregory S. Kaltenecker, David L. Evans, Frank J. Nicoletti, Jean-François Therrien, Olin Allen, John Delong

School of Biological Sciences: Faculty Publications

Many American kestrel (Falco sparverius) populations are declining across North America. Potential causes include mortality from reduction in food availability, a changing climate, habitat degradation, an increase in avian predators, disease, and toxins. We analyzed American kestrel count and banding data from seven raptor migration sites throughout North America with at least 20 years of migration data. We used count data to determine the year at which the kestrel population began a significant decline and then used banding records to determine whether body mass and wing chord declined after this point. We found reductions in kestrel body mass at three …

Putting The I In Science, Naomi Kirkvold

Honors Program: Expanded Learning Clubs

This club gets kids interested in science in ways that they may not have experienced in a classroom by doing weekly experiments.

Establishing Enhanced Learning Outcomes In Science For First Generational Undergraduate College Students, Marianna Burks

Department of Teaching, Learning, and Teacher Education: Theses and Other Student Research

First-generation students represent an increasing percentage of the demographic for college and university enrollment at both the undergraduate and graduate levels. Since 2001, results from the National Center for Education Statistics Longitudinal Study, indicates ‘higher percentages of first-generations college students attended public postsecondary institutions-76 vs. 72%’ (Redford & Hoyer, 2017). There is insufficient research, however, concerning how first-generation students’ needs are different, even unique, from those students who are second- generation and beyond attending college (National Center for Educational Statistics, 2017). Since this increase of students enrolling in post-secondary education, ‘understanding the needs of first-generation students is imperative more now …

Detection Of Heteroplasmic Single Nucleotide Polymorphisms Using Melt Curve Analysis And Dual Labeled Fluorescent Probes, Emily Jezewski

Honors Program: Senior Projects (Public)

Plant mitochondrial genomes are strange – they are unusually large, consist of huge amounts of non-coding DNA, and contain of several overlapping regions throughout the genome. The genome is made of several different sized linear and circular molecules and different mitochondria within a cell will have different pieces of the genome. Even if multiple mitochondria contain the same region of the genome, these sequences can differ by single nucleotide polymorphisms (SNPS). This is known as heteroplasmy. Heteroplasmy has been documented in Arabidopsis thaliana using whole-genome sequencing data. While heteroplasmy is well-documented, its existence in the mitochondrial genome is unexpected and …

Plant Mitochondrial Genome Evolution And Structure Has Been Shaped By Double-Strand Break Repair And Recombination, Emily Wynn

School of Biological Sciences: Dissertations, Theses, and Student Research

Plant mitochondrial genomes are large but contain a small number of genes. These genes have very low mutation rates, but genomes rearrange and expand at significant rates. We propose that much of the apparent complexity of plant mitochondrial genomes can be explained by the interactions of double-strand break repair, recombination, and selection. One possible explanation for the disparity between the low mutation rates of genes and the high divergence of non-genes is that synonymous mutations in genes are not truly neutral. In some species, rps14 has been duplicated in the nucleus, allowing the mitochondrial copy to become a pseudogene. By …

The Ecological Niche Of Echinococcus Multilocularis In North America: Understanding Biotic And Abiotic Determinants Of Parasite Distribution With New Records In New Mexico And Maryland, United States, Sebastian Botero-Cañola, Altangerel Tsogtsaikhan Dursahinhan, Sara E. Rácz, Parker V. Lowe, John E. Ubelaker, Scott Lyell Gardner

Scott L. Gardner Publications

English abstract: Understanding the factors shaping the niche of parasites and its expression over geographical space and through time continues to be a modern scientific challenge with the results of research in this area directly influencing both theoretical and applied biology. This is especially important for proactive management of zoonotic parasites such as Echinococcus multilocularis, the etiologic agent of alveolar echinococcosis. Echinococcus multilocularis has a Holarctic distribution; with its geographic range and prevalence increasing recently in areas of the western Palearctic, while its distribution dynamics are poorly understood in the Nearctic. In this paper, we use an ecological niche …

Status Of The Plains Harvest Mouse (Reithrodontomys Montanus Griseus) In Eastern Nebraska, Keith Geluso, Greg D. Wright

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In eastern Nebraska, current status of the Plains Harvest Mouse (Reithrodontomys montanus griseus) is not well understood. Infrequent captures during the last century have led to a paucity of information regarding this taxon, and some researchers postulate that its distribution has contracted in the state. In 2008, we conducted a field survey for R. m. griseus in eastern Nebraska, amassed prior specimen records, and examined most of the specimens for this subspecies from the state to better understand its distribution, natural history, and subspecific status. In our field efforts, we only captured a single individual despite …

Enzyme Kinetics Of Dutpase From The Planarian Dugesia Ryukyuensis, Shahanoor Alam, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

Objective: Planarians including Dugesia ryukyuensis (Dr) have strong regenerative abilities that require enhanced DNA replication. Knockdown of the DUT gene in Dr, which encodes deoxyuridine 5′-triphosphate pyrophosphatase (dUTPase), promotes DNA fragmentation, inhibits regeneration, and eventually leads to death. dUTPase catalyzes the hydrolysis of dUTP to dUMP and pyrophosphate. dUTPase is known to prevent uracil misincorporation in DNA by balancing the intracellular ratio between dUTP and dTTP, and contributes to genome stability. Nevertheless, the catalytic performance of Dr-dUTPase has not been reported.

Results: To confirm the catalytic activity of Dr-dUTPase, we cloned and expressed Dr-DUT in E. coli. Then, we purified …

Microbial Community Of Saline, Alkaline Lakes In The Nebraska Sandhills Based On 16s Rrna Gene Amplicon Sequence Data, Nicole A. Fiore, David D. Dunigan, Julie J. Shaffer, Ryan Roberts, Sanjay Antony-Babu, Bradley A. Plantz, Kenneth W. Nickerson, Andrew K. Benson, Karrie A. Weber

School of Biological Sciences: Faculty Publications

The Nebraska Sandhills region contains over 1,500 geochemically diverse interdunal lakes, some of which are potassium rich, alkaline, and hypersaline. Here, we report 16S rRNA amplicon pyrosequencing data on the water and sediment microbial communities of eight alkaline lakes in the Sandhills of western Nebraska.