Population Biology Commons^™

Popgenhelpr: An R Package To Streamline And Facilitate Informed Population Genomic Analyses And Visualization Of Genetic Ancestry, Diversity And Differentiation, Keaka Farleigh, Mason O. Murphy, Christopher Marie Blair, Tereza Jezkova

Publications and Research

Analysing large population genomic datasets requires an interdisciplinary skillset. Beyond a knowledge base in genetics and population biology, population genomic analyses involve computer science and statistics, representing a barrier for researchers without experience in those fields. PopGenHelpR seeks to lower this barrier by enabling researchers to perform population genomic analyses and generate near-publication quality figures in a streamlined and informed fashion. PopGenHelpR allows users to estimate genetic diversity within populations as well as differentiation among populations and individuals from single nucleotide polymorphism data. PopGenHelpR includes commonly used measures such as observed heterozygosity and FST. PopGenHelpR also provides five …

A Review Of Mockingbird Song, Jacqueline Milander

Student Theses

The northern mockingbird (Mimus polyglottos) is known for its large repertoire and highly versatile song patterns.  It is a frequent mimic that is thought to continue learning sounds from its environment for the duration of its life.  Utilizing available song studies, this is a comprehensive review of northern mockingbird song, including learning, mimicry, repertoires, song dependence on seasonal cyclicity, and song function, particularly interspecific territoriality. While much discussion has surrounded the idea that northern mockingbirds engage in interspecific territoriality and that vocal mimicry functions in intersexual selection, this review provides new insight into the possibility that latitudinal differences among populations …

Hidden In The Mist: Three New Species Of Salamanders Of The Genus Pseudoeurycea (Amphibia: Plethodontidae) From Oaxaca, Mexico, Eduardo A. Aguilar-Herrera, Salomón Sanabria-Urbán, Dulce L. Flores-Martínez, José David Gómez-Tapia, Misael Seba-Chacha, Leopoldo D. Vázquez-Reyes, Francisco A. Rivera-Ortíz, Patricia Ramírez-Bastida, Bruno Cortés-Ortiz, R. Alejandro Calzada-Arciniega, Etienne U. Avila-Ortega, Dónovan I. Víquez-Vega, Omar Hernández-Ordoñez, Christopher Blair, Víctor H. Jiménez-Arcos

Publications and Research

We describe three new species of lungless salamanders (Plethodontidae) in the genus Pseudoeurycea from Cerro Rabon, located on the eastern slopes of the Sierra Mazateca, Oaxaca, Mexico. This mid-elevation mountain, largely surrounded by warmer lowlands, remains relatively understudied. We present molecular and morphological evidence distinguishing the three new species from their congeners. According to our phylogenetic analysis, one of the new species belongs to the P. leprosa group, while the other two are members of the P. juarezi group. Notably, one of the new species represents the fourth worm salamander known from west of the Isthmus of Tehuantepec, and another …

Hybridization And Introgression In Marine Invertebrates: Population Genomics Of Phymactis Papillosa And Asterias Sea Stars, Christopher J. Dookie

Dissertations and Theses

Hybridization and introgression are evolutionary significant processes in marine invertebrates (Sanford & Kelly,2011) yet genome-wide investigations of gene flow in these taxa remain limited relative to vertebrate systems (Marchi et al., 2021). This thesis presents genomic analyses of hybridization and introgression in two marine invertebrates occupying contrasting oceanographic settings and characterized by contrasting genomic datasets: restriction-site associated DNA sequencing (RADseq) SNP data for the eastern Pacific sea anemone Phymactis papillosa and whole genome sequencing (WGS) data for the North Atlantic sea stars Asterias rubens and Asterias forbesi. For each system, I applied coalescent-based species tree inference using CASTER (Zhang …

Exploring The Role Of Ecological Traits In Shaping Spatial Patterns Of Genetic Diversity, Rilquer Mascarenhas Da Silva

Dissertations, Theses, and Capstone Projects

The field of comparative phylogeography aims at uncovering common underlying causes for shared patterns of diversity and diversification at the population level. However, it is now widely accepted that intraspecific genetic diversity patterns can differ considerably across co-occurring taxa due to ecological processes acting at the population level (and influencing individual movement and abundance). To model the processes underlying lineage diversification and demographic shifts in response to environmental changes, phylogeographers and population geneticists are now faced with the challenge of incorporating measurements of species ecological traits into their molecular studies. This dissertation aimed at investigating how different types of ecological …

The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French

Dissertations, Theses, and Capstone Projects

The spatial distribution of genetic diversity is of interest to biodiversity scientists and conservationists and is a fundamental metric of biodiversity. Genetic diversity patterns across spatial and taxonomic scales contain information about population and assemblage dynamics that can convey their resilience to environmental change. Ectotherms are especially linked to their environments and may be especially sensitive to fluctuations in the environment over time. Herein, I investigate global and regional patterns of genetic diversity in two groups of ectotherms, insects and lizards, to understand the relationship between environmental change and genetic diversity, from populations to assemblages. Overall, my research aims to …

Population Genomics, Ecology And Conservation Of Asterias Sea Stars In The North Atlantic, Melenia I. Giakoumis

Dissertations, Theses, and Capstone Projects

Uncovering how species respond to environmental change is a central question in biology (Ehrlén & Morris 2015; Habibullah et al. 2022). It is the key to elucidating the past, understanding the present and predicting the future of species’ population dynamics. This dissertation investigates the influence of environmental change on intertidal species’ distributions and genomics at several timescales, with implications for conservation.

Environmental changes have occurred throughout history, on a geological scale, and have shaped the global patterns of species’ distributions and population sizes. Biologists have long studied how geological history has shaped species distributions (Sanmartín 2012) in both terrestrial (Liu …

Reproductive Traits And Change In Body Shape Of Neonates In The Oak Forest Skink, Plestiodon Lynxe, Manuel Feria-Ortiz, Uri Omar García-Vázquez, Carlos Joaquín Pavón-Vázquez, Adrián Nieto-Montes De Oca

Publications and Research

Reproductive traits are critically important for understanding how organisms adapt to their respective environments. In this study, we provide information on relative litter mass (RLM) and other litter and neonate related characters of nine female Plestiodon lynxe captured in the field. We also recorded seven body dimensions in 16 neonates and 15 two-month juveniles, and on the basis of these dimensions we compared the body shape of these two age classes to detect changes in the proportions of body parts. The average litter size (4.55) is larger than that found in other viviparous species of Plestiodon, but smaller than …

Genomic Insights Into Mechanisms Of Microbial Evolution And Evolution-Inspired Strategies To Combat Pathogen Diversity, Saymon Akther

Dissertations, Theses, and Capstone Projects

We live in an era of emerging infectious diseases that are increasingly common, rapidly spreading, and gravely devastating. Lyme disease, caused by bacteria belonging to the genus Borreliella, is rapidly rising in the Northern Hemisphere because of geographic range expansion of both the tick vectors and the pathogens. Evolutionary comparative analysis of Borreliella genomes is a key to understanding the phylogeographic history and mechanisms of their global diversification. Moreover, genomic variations in Borreliella associated with human pathogenicity, e.g., at loci encoding cell-surface antigens interacting with the vertebrate hosts, have not been fully identified. Similarly, the ongoing COVID-19 pandemic, caused …

Population Structure Of The Lizard Ecpleopus Gaudichaudii Coincides With A Biogeographic Barrier - The Doce River, Alexander J. Garretson

Dissertations and Theses

Intraspecific genetic variation is an integral component of diversification and the accumulation of biodiversity. The degree to which isolated populations of the same species are genetically structured in geographical space is impacted by a variety of mechanisms. In this study, I document patterns and discuss possible drivers of genetic structure within Ecpleopus gaudichaudii, a lizard species endemic to the Atlantic Forest of Brazil. For that, I assembled ddRadseq sequences from 48 individuals across much of the range of the E. gaudichaudii and analyzed its population structure. I created an intraspecific phylogeny for this group utilizing RAxML and conducted a …

Genome-Scale Data Reveal Deep Lineage Divergence And A Complex Demographic History In The Texas Horned Lizard (Phrynosoma Cornutum) Throughout The Southwestern And Central Us, Nicholas Finger, Keaka Farleigh, Jason T. Bracken, Adam D. Leaché, Olivier François, Ziheng Yang, Tomas Flouri, Tristan Charran, Tereza Jezkova, Dean A. Williams, Christopher Blair

Publications and Research

The southwestern and central US serve as an ideal region to test alternative hypotheses regarding biotic diversification. Genomic data can now be combined with sophisticated computational models to quantify the impacts of paleoclimate change, geographic features, and habitat heterogeneity on spatial patterns of genetic diversity. In this study we combine thousands of genotyping-by-sequencing (GBS) loci with mtDNA sequences (ND1) from the Texas Horned Lizard (Phrynosoma cornutum) to quantify relative support for different catalysts of diversification. Phylogenetic and clustering analyses of the GBS data indicate support for at least three primary populations. The spatial distribution of populations appears concordant …

The Effects Of Climate And Demographic History In Shaping Genomic Variation Across Populations Of The Desert Horned Lizard (Phrynosoma Platyrhinos), Keaka Farleigh, Sarah A. Vladimirova, Christopher Blair, Jason T. Bracken, Nazila Koochekian, Drew R. Schield, Daren C. Card, Nicholas Finger, Jonathan Henault, Adam D. Leaché, Todd A. Castoe, Tereza Jezkova

Publications and Research

Species often experience spatial environmental heterogeneity across their range, and populations may exhibit signatures of adaptation to local environmental characteristics. Other population genetic processes, such as migration and genetic drift, can impede the effects of local adaptation. Genetic drift in particular can have a pronounced effect on population genetic structure during large-scale geographic expansions, where a series of founder effects leads to decreases in genetic variation in the direction of the expansion. Here, we explore the genetic diversity of a desert lizard that occupies a wide range of environmental conditions and that has experienced post-glacial expansion northwards along two colonization …

Genomic And Ecological Dimensions Of Malagasy Reptile And Amphibian Biodiversity, Arianna L. Kuhn

Dissertations, Theses, and Capstone Projects

A long history of isolation coupled with complex topographic and ecological landscapes makes Madagascar ideal for exploring the historical factors that have shaped patterns of population diversity and endemism. Many species-level studies have suggested Late Quaternary climate change may have influenced population dynamics in the tropics, but Madagascar’s ecologically unique biomes or individual species properties may have driven idiosyncratic responses to these shifts. Using community-scale population genetic data I implement a hierarchical approximate Bayesian computation (hABC) approach to evaluate the degree of synchronous population expansion during glacial cycles across herpetofaunal assemblages both within and across discrete biomes and taxonomic groups. …

The Insular Herpetofauna Of Mexico: Composition, Conservation, And Biogeographic Patterns, Juan Valentín Pliego‐Sánchez, Christopher Blair, Aníbal H. Díaz De La Vega‐Pérez, Víctor H. Jiménez‐Arcos

Publications and Research

We compile a Mexican insular herpetofaunal checklist to estimate endemism, conservation status, island threats, net taxonomic turnover among six biogeographic provinces belonging to the Nearctic and Neotropical regions, and the relationships between island area and mainland distance versus species richness. We compile a checklist of insular herpetofaunal through performing a literature and collection review. We define the conservation status according to conservation Mexican law, the Red List of International Union for Conservation of Nature, and Environmental Vulnerability Scores. We determine threat percentages on islands according to the 11 major classes of threats to biodiversity. We estimate the net taxonomic turnover …

A New Vine Snake (Reptilia, Colubridae, Oxybelis) From Peru And Redescription Of O. Acuminatus, Robert C. Jadin, Michael J. Jowers, Sarah A. Orlofske, William E. Duellman, Christopher Blair, John C. Murphy

Publications and Research

The Brown Vine Snake, Oxybelis aeneus, was until recently considered a single species, distributed from southern Arizona through the Neotropics into southeastern Brazil. However, newly conducted research restructured the species with a substantial taxonomic revision, recognizing five additional taxa (i.e. O. koehleri, O. microphthalmus, O. potosiensis, O. rutherfordi, O. vittatus) in this species complex. This revision focused on populations in North America, Central America, and northern South America while neglecting the southern portion of its distribution. Here, we examine the taxonomic history of the complex and use it along with specimen data to resurrect O. acuminatus from southeastern Brazil. Finally, …

The Relationships Between Spawning Horseshoe Crabs And Egg Densities: Recommendations For The Assessment Of Populations And Habitat Suitability, Mark L. Botton Phd, Christina P. Colon Phd, Matthew Sclafani Phd, Robert E. Loveland Phd, Susan Elbin Phd, Kaitlyn Parkins

Publications and Research

1. Horseshoe crab population sizes and trends have been previously studied using surveys of spawning adults and counts of eggs from surface (top 5 cm) and deep (20 cm) sediment samples. The correlations between surface and deep eggs were studied at two locations, Delaware Bay and Jamaica Bay, USA, and the correlations between egg densities and spawning counts were examined in Jamaica Bay. 2. There were significantly higher densities of eggs in deep sediments than in surface sediments. Only about 10% of the variability in surface egg density was explained by deep egg density. The numerical patterns between surface and …

Resilience: Insights From The U.S. Longterm Ecological Research Network, Jane Cowles, Laura Templeton, John J. Battles, Peter J. Edmunds, Robert C. Carpenter, Stephen R. Carpenter, Michael Paul Nelson, Natalie L. Cleavitt, Timothy J. Fahey, Peter M. Groffman, Joe H. Sullivan, Maile C. Neel, Gretchen J. A. Hansen, Sarah Hobbie, Sally J. Holbrook, Clare E. Kazanski, Eric W. Seabloom, Russell J. Schmitt, Emily H. Stanley, Alan J. Tepley, Natalie S. Van Doorn, Jake M. Vander Zanden

Advanced Science Research Center

Ecosystems are changing in complex and unpredictable ways, and analysis of these changes is facilitated by coordinated, long-term research. Meeting diverse societal needs requires an understanding of what populations and communities will be dominant in 20, 50, and 100 yr. This paper is a product of a synthesis effort of the U.S. National Science Foundation funded Long-Term Ecological Research (LTER) network addressing the LTER core research area of populations and communities. This analysis revealed that each LTER site had at least one compelling story about what their site would look like in 50 or 100 yr. As the stories were …

Ecology And Evolution, David J. Lohman

Open Educational Resources

Introduction to the basic principles of ecology and evolutionary biology emphasizing quantitative approaches and hypothesis testing. Scientific reasoning, computer literacy, and writing skills are developed in the laboratory.

Assessment Of Wild Ring-Tailed Lemur (Lemur Catta) Populations In Southwestern Madagascar With Implications For The Illegal Pet Trade, Samantha D. Calkins

Theses and Dissertations

Accurate population estimates are critical to inform conservation management of species. Incomplete sampling can lead to population underestimates and lacking conservation efforts. Population surveys are important for assessing human and animal welfare to allow for targeted conservation action. Recent ring-tailed lemur (Lemur catta) surveys have led researchers to conclude that L. catta populations are crashing. This has generated much attention and alarm, but may also be based on incomplete information. To better understand population dynamics, more thorough sampling is needed. Here, we survey five such sites to reassess the presence and abundance of L. catta in these locations. …

Standards For Distribution Models In Biodiversity Assessments, Miguel B. Araújo, Robert P. Anderson, A. Márcia Barbosa, Colin M. Beale, Carsten F. Dormann, Regan Early, Raquel A. Garcia, Antoine Guisan, Luigi Maiorano, Babak Naimi, Robert B. O'Hara, Niklaus E. Zimmermann, Carsten Rahbek

Publications and Research

Demand for models in biodiversity assessments is rising, but which models are adequate for the task? We propose a set of best-practice standards and detailed guidelines enabling scoring of studies based on species distribution models for use in biodiversity assessments. We reviewed and scored 400 modeling studies over the past 20 years using the proposed standards and guidelines. We detected low model adequacy overall, but with a marked tendency of improvement over time in model building and, to a lesser degree, in biological data and model evaluation. We argue that implementation of agreed-upon standards for models in biodiversity assessments would …

Using Molecular Markers To Trace The Population History Of Volant Organisms At Differing Temporal Scales, Noah A. Burg

Dissertations, Theses, and Capstone Projects

Using molecular markers to test phylogenetic and phylogeographic hypotheses is critical for tracking the population origin of invasive, introduced species (Chapter 2, Chapter 4) and to identify the systematic relationships of disparate lineages at both shallow and deep evolutionary time scales (Chapters 3, Chapter 4). In this thesis, Sanger Sequencing was used to generate datasets based on fresh and preserved tissue from specimens collected in the field, as well as museum tissue vouchers granted from various institutions in the US and Europe. In combining these source materials, data were generated for three focal studies: 1) In the first research section …

Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer

Publications and Research

The evolutionary emergence of humans’ remarkably economical walking gait remains a focus of research and debate, but experi- mentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental mea- surements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal–terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by …

Of Rats And Men, Thomas S. Walsh

Capstones

This capstone is a data-driven investigation into New York City's rat problem. By using publicly available government data to map rat activity in NYC, I identified several socio-economic variables that correlate with rat populations at the community district, borough, and city-scale. I used these findings (mainly that rat problems are linked to lower incomes) as the basis of an investigation, which includes interviews with residents, experts, and city officials. Prof. Bobby Corrigan, urban rodentologist and formerly with the NYC Department of Health criticizes the city's efforts for the first time on the record.

https://thomasseiyawalsh.wixsite.com/ratstone

Climate Matching Drives Spread Rate But Not Establishment Success In Recent Unintentional Bird Introductions, Pedro Abellán, José L. Tella, Martina Carrete, Laura Cardador, José D. Anadón

Publications and Research

Understanding factors driving successful invasions is one of the cornerstones of invasion biology. Bird invasions have been frequently used as study models, and the foundation of current knowledge largely relies on species purposefully introduced during the 19th and early 20th centuries in countries colonized by Europeans. However, the profile of exotic bird species has changed radically in the last decades, as birds are now mostly introduced into the invasion process through unplanned releases from the worldwide pet and avicultural trade. Here we assessed the role of the three main drivers of invasion success (i.e., event-, species-, and location-level factors) on …

Lichen Conservation In Eastern North America: Population Genomics, Climate Change, And Translocations, Jessica Allen

Dissertations, Theses, and Capstone Projects

Conservation biology is a scientific discipline that draws on methods from diverse fields to address specific conservation concerns and inform conservation actions. This field is overwhelmingly focused on charismatic animals and vascular plants, often ignoring other diverse and ecologically important groups. This trend is slowly changing in some ways; for example, increasing number of fungal species are being added to the IUCN Red-List. However, a strong taxonomic bias still exists. Here I contribute four research chapters to further the conservation of lichens, one group of frequently overlooked organisms. I address specific conservation concerns in eastern North America using modern methods. …

Flight Of The Freshwater Fish, Michael H. Wilson

Capstones

Michael H. Wilson

Capstone Abstract

December 27, 2016

Flight of the Freshwater Fish

The Hudson River provides for millions of people as a path for commercial and private transportation, a source of food and energy, and perhaps most importantly for many living in the tri-state area as a destination for recreation and relaxation. The most overlooked feature of the river is how the wildlife shows clear signs of a changing climate and rapid environmental response to the impacts of global warming on the river.

Entire populations of fish species in the lower Hudson have been forced to leave the river …

Diversity-Dependent Cladogenesis Throughout Western Mexico: Evolutionary Biogeography Of Rattlesnakes (Viperidae: Crotalinae: Crotalus And Sistrurus), Christopher Blair, Santiago Sánchez-Ramírez

Publications and Research

Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the …

Landscape Genetics Of Leaf-Toed Geckos In The Tropical Dry Forest Of Northern Mexico, Christopher Blair, Victor H. Jimenez-Arcos, Fausto R. Mendez De La Cruz, Robert W. Murphy

Publications and Research

Habitat fragmentation due to both natural and anthropogenic forces continues to threaten the evolution and maintenance of biological diversity. This is of particular concern in tropical regions that are experiencing elevated rates of habitat loss. Although less well-studied than tropical rain forests, tropical dry forests (TDF) contain an enormous diversity of species and continue to be threatened by anthropogenic activities including grazing and agriculture. However, little is known about the processes that shape genetic connectivity in species inhabiting TDF ecosystems. We adopt a landscape genetic approach to understanding functional connectivity for leaf-toed geckos (Phyllodactylus tuberculosus) at multiple sites …

What To Eat Now? Shifts In Polar Bear Diet During The Ice-Free Season In Western Hudson Bay, Linda J. Gormezano, Robert F. Rockwell

Publications and Research

Under current climate trends, spring ice breakup in Hudson Bay is advancing rapidly, leaving polar bears (Ursus maritimus) less time to hunt seals during the spring when they accumulate the majority of their annual fat reserves. For this reason, foods that polar bears consume during the ice-free season may become increasingly important in alleviating nutritional stress from lost seal hunting opportunities. Defining how the terrestrial diet might have changed since the onset of rapid climate change is an important step in understanding how polar bears may be reacting to climate change. We characterized the current terrestrial diet of polar bears …

What Is The Predictive Power Of The Colobine Protein-To-Fiber Model And Its Conservation Value?, Jan F. Gogarten, Melissa Guzman, Colin A. Chapman, Aerin L. Jacob, Patrick A. Omeja, Jessica Rothman

Publications and Research

Predicting variation in animal abundance across time and space has proven very difficult; however, a model exists to predict the biomass of small folivorous primates that has considerable correlative support. This model suggests that the protein-to-fiber ratio of leaves in a habitat can predict folivore biomass. Here we present an experimental test of this protein-to-fiber model to assess if the number of infant monkeys per female and group size can be predicted based on the leaf chemistry of a habitat. We expected regenerating forest in Kibale National Park, Uganda to have leaves with higher concentrations of crude protein and lower …