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Articles 31 - 60 of 330

Full-Text Articles in Ecology and Evolutionary Biology

Evolution Of Floral Microbes And The Resulting Effects On Pollinator Preference, Hailey Hatch May 2022

Evolution Of Floral Microbes And The Resulting Effects On Pollinator Preference, Hailey Hatch

Undergraduate Honors Capstone Projects

Floral microbes are an overlooked aspect of the extended floral phenotype. Through altering floral nectar chemistry, they can mediate interactions between flowers, pollinators, and other floral microbes, with significant implications for plant and pollinator health. Interactions between floral microbes and pollinators are critically important to understand, as pollinators provide important ecosystem services in both natural and agriculture systems. Here, I explored how floral nectar traits affected both evolution and competition within the floral yeast Metschnikowia reukaufii, the floral bacterium Bacillus subtilis, and other microbes isolated from Brassica rapa nectar, an important plant model system and oilseed crop. To …


In-Class Evolution Discussions Change Bible Interpretation, Jessica Abele Mar 2022

In-Class Evolution Discussions Change Bible Interpretation, Jessica Abele

Library/Life Sciences Undergraduate Poster Competition 2022

Conflict between religion and evolution is a major barrier for religious biology students. Educators have been working to increase evolution acceptance by using a variety of methods (e.g., increasing evolution knowledge, addressing creationism in class, etc.) with little success. However, recent research shows using a reconciliatory approach to evolution and religion increases evolution acceptance while overall religiosity is unaffected (Lindsay et al., 2019).


Phylogenomic Discordance Suggests Polytomies Along The Backbone Of The Large Genus Solanum, Edeline Gagnon, Rebeccca Hilgenhof, Andrés Orejuela, Angela J. Mcdonnell, Gaurav Sablok, Xavier Aubriot, Leandro Giacomin, Yuri Gouvêa, Thamyris Bragionis, João Renato Stehmann, Lynn Bohs, Steven Dodsworth, Christopher T. Martine, Péter Poczai, Sandra Knapp, Tiina Särkinen Feb 2022

Phylogenomic Discordance Suggests Polytomies Along The Backbone Of The Large Genus Solanum, Edeline Gagnon, Rebeccca Hilgenhof, Andrés Orejuela, Angela J. Mcdonnell, Gaurav Sablok, Xavier Aubriot, Leandro Giacomin, Yuri Gouvêa, Thamyris Bragionis, João Renato Stehmann, Lynn Bohs, Steven Dodsworth, Christopher T. Martine, Péter Poczai, Sandra Knapp, Tiina Särkinen

Faculty Journal Articles

Premise of the study

Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of gene-tree discordance in Solanum, one of the largest flowering plant genera that includes the cultivated potato, tomato, and eggplant, as well as 24 minor crop plants.

Methods

A densely sampled species-level phylogeny of Solanum is built using unpublished and publicly available Sanger sequences comprising 60% of all accepted species (742 spp.) …


Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie Jan 2022

Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie

Master's Theses

Life-history characteristics (e.g., age and growth) have been used extensively to understand the temporal population dynamics of fish species, but less so within a phylogenetic framework. This study investigates life-history characteristics within the suborder Gadoidei (order: Gadiformes) and to test the extent of phylogenetic signal for those characteristics. To accomplish this, a phylogeny of Gadoidei was first constructed based on both mitochondrial and nuclear genes. Within this phylogenetic framework, life-history traits, including growth rate, age at maturity, and longevity, as well as ecological data, such as water depth and diet type, were mapped to the phylogeny using parsimony analysis to …


Nutrient Scarcity And Cellular Cooperation In A Clonal Hydroid, Weam S. El Rahmany Jan 2022

Nutrient Scarcity And Cellular Cooperation In A Clonal Hydroid, Weam S. El Rahmany

Graduate Research Theses & Dissertations

Biological complexity forms when lower-level units (e.g., genes, cells, organisms) cooperatively band together. This complexity may be exemplified by multicellularity, the cooperation between the cells of the same species, or symbiosis, cooperation between the cells of different species. This cooperation is under continual threat, as defection, the opposite of cooperation, is favored by default by lower-level units (i.e., cells). Animal cancers may be the most well-known phenomena that exemplify the concept of cellular defection. Cancer cells have been shown to feature morphological and metabolic traits, developed through differential gene expression or mutations, that favor their growth at the cost of …


Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein Jan 2022

Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein

Theses and Dissertations

In this study I attempted to further resolve the population genetic structure in the Prothonotary Warbler (Protonotaria citrea), and conducted an outlier SNP analysis and exploratory gene ontology analysis to investigate potential ongoing natural selection in the species. This analysis of population structure confirms previous work by DeSaix et al. (2019), where weak population structure was observed between eastern sites along the Atlantic Coastal Plain, and western sites in the Mississippi Alluvial Valley, possibly due to a genetic discontinuity across the Appalachian Mountains. I conducted two forms of outlier SNP analyses, a principal component analysis (PCA)-based approach to identify SNPs …


Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland Jan 2022

Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland

Electronic Theses and Dissertations

Little information is available concerning the distribution of genetic diversity in non-salmonid, non-imperiled, freshwater fish. In order to fill in this knowledge gap, I conducted a population genomics survey in Redbreast Sunfish (Lepomis auritus; RBS), a widespread, generalist species distributed along the Atlantic slope rivers of eastern North America. I sampled four basins (ACF, Savannah, Roanoke, and James) at eight sites each with a factorial experimental design. Sites were distributed among coastal plain, Piedmont, or mountain ecoregions in order to capture the greatest range of environmental states experienced by RBS, with the intention of finding evidence for local adaptation to …


Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas Jan 2022

Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas

Graduate College Dissertations and Theses

Introduced plants face many ecological and evolutionary challenges when establishing in a new range, such as strong abiotic stressors and potentially novel selective environments. One such abiotic stress is water availability, which is a strong selective force shaping physiological and phenological traits that enable plants to tolerate or avoid drought stress. Despite the challenges of establishing in a new range, thousands of species have become invasive in recent centuries. Two hypotheses that may explain how a species is able to withstand stress in its introduced range are preadaptation, which posits that species are adapted to similar environments in their native …


Lipidomic Analysis Of Various Developmental Stages Of Physcomitrium Patens, Deepshila Gautam Dec 2021

Lipidomic Analysis Of Various Developmental Stages Of Physcomitrium Patens, Deepshila Gautam

Electronic Theses and Dissertations

Lipids maintain fluidity of the cell membrane during the lifetime of all organisms. The moss Physcomitrium patens, an early land plant, enters reproductive phase under cold (15°C) conditions relative to its gametophytes (22°C). Thus, we hypothesized that their lipid content and composition would be distinct. Using ESI-MS/MS, we showed that the content and acyl composition of 11 lipid classes varied during development. Galactolipids were abundant in gametophytes but insignificant in sporophytes; among phospholipids, phosphatidylcholine was predominant in both phases. Although, sporophytes contained around five-fold less lipids than the gametophyte, their phosphatidic acid content, which accumulates during stress, was 18-fold …


(Non)Parallel Developmental Mechanisms In Vertebrate Appendage Reduction And Loss, Samantha Swank, Thomas Sanger, Yoel E. Stuart Nov 2021

(Non)Parallel Developmental Mechanisms In Vertebrate Appendage Reduction And Loss, Samantha Swank, Thomas Sanger, Yoel E. Stuart

Biology: Faculty Publications and Other Works

Appendages have been reduced or lost hundreds of times during vertebrate evolution. This phenotypic convergence may be underlain by shared or different molecular mechanisms in distantly related vertebrate clades. To investigate, we reviewed the developmental and evolutionary literature of appendage reduction and loss in more than a dozen vertebrate genera from fish to mammals. We found that appendage reduction and loss was nearly always driven by modified gene expression as opposed to changes in coding sequences. Moreover, expression of the same genes was repeatedly modified across vertebrate taxa. However, the specific mechanisms by which expression was modified were rarely shared. …


Resource Allocation And Phenotypic Plasticity Of Simultaneous Hermaphroditic Turtle Barnacles (Chelonibia Testudinaria), Kevin C. Cash Nov 2021

Resource Allocation And Phenotypic Plasticity Of Simultaneous Hermaphroditic Turtle Barnacles (Chelonibia Testudinaria), Kevin C. Cash

All HCAS Student Capstones, Theses, and Dissertations

This research addresses the knowledge gap of phenotypic plasticity in a commonly found and important species of epizoic barnacle, Chelonibia testudinaria. Limited research has been published regarding how phenotypic expression is mediated the spatial distribution of barnacles on a mobile host. To investigate this potential relationship, barnacles were collected from the backs of turtles along the beaches of Fort Lauderdale Florida. These barnacles were assessed for various phenotypic traits as well as their corresponding spatial distribution on the turtle carapace. Barnacles were safely removed from the carapace using a chisel before their preservation in ethanol. Barnacles were then numbered …


The Evolution Of Bioluminescence Across The Shrimp Family Sergestidae: A Genomic Skimming And Phylogenetic Approach, Charles G. Golighty Iii Nov 2021

The Evolution Of Bioluminescence Across The Shrimp Family Sergestidae: A Genomic Skimming And Phylogenetic Approach, Charles G. Golighty Iii

FIU Electronic Theses and Dissertations

The family Sergestidae provide a unique system for studying the evolution of bioluminescence, with species possessing one of three distinct forms of photophores. This study capitalizes on molecular data to construct a genus-level phylogeny of sergestid shrimp. “Genome skimming” was implemented, capturing mitochondrial genomic data across 19 species. Additional individuals were incorporated through Sanger sequencing of four partial gene regions. The -sergestes group of genera was recovered as non-monophyletic, with the -sergia group of genera being recovered as monophyletic. Ancestral state reconstructions of light organ type indicate the organs of Pesta photophore is the ancestral state for the …


Phenotype Bias Determines How Natural Rna Structures Occupy The Morphospace Of All Possible Shapes, Fatme Ghaddar, Dr Kamaludin Dingle, Dr Petr Sulc, Prof Ard A. Louis Sep 2021

Phenotype Bias Determines How Natural Rna Structures Occupy The Morphospace Of All Possible Shapes, Fatme Ghaddar, Dr Kamaludin Dingle, Dr Petr Sulc, Prof Ard A. Louis

Undergraduate Research Symposium

The relative prominence of developmental bias versus natural selection is a long standing controversy in evolutionary biology. Here we demonstrate quantitatively that developmental bias is the primary explanation for the occupation of the morphospace of RNA secondary structure (SS) shapes. By using the RNAshapes method to define coarse-grained SS classes, we can measure the frequencies that non-coding RNA SS shapes appear in nature. Our main findings are firstly that only the most frequent structures appear in nature; the vast majority of possible structures in the morphospace have not yet been explored. Secondly, and perhaps more surprisingly, these frequencies are accurately …


Factors Influencing Primate Hair Microbiome Diversity, Catherine Kitrinos Sep 2021

Factors Influencing Primate Hair Microbiome Diversity, Catherine Kitrinos

Masters Theses

Primate hair is both a substrate upon which essential social interactions occur and an important host-pathogen interface. As commensal microbes provide important immune functions for their hosts, understanding the microbial diversity in primate hair could provide insight into primate immunity and disease transmission. While studies of human hair and skin microbiomes show differences in microbial communities across body regions, little is known about the nonhuman primate hair microbiome. In this study, we collected hair samples (n=159) from 8 body regions across 12 nonhuman primate species housed at 3 US institutions to examine 1) the diversity and composition of the primate …


Coevolution Of Hosts And Pathogens In The Presence Of Multiple Types Of Hosts, Evan J. Mitchell Aug 2021

Coevolution Of Hosts And Pathogens In The Presence Of Multiple Types Of Hosts, Evan J. Mitchell

Electronic Thesis and Dissertation Repository

How will hosts and pathogens coevolve in response to multiple types of hosts? I study this question from three different perspectives. First, I model a scenario in which hosts are categorized as female or male. Hosts invest resources in maintaining their immune system at a cost to their reproductive success, while pathogens face a trade-off between transmission and duration of infection. Importantly, female hosts are also able to vertically transmit an infection to their newborn offspring. The main result is that as the rate of vertical transmission increases, female hosts will have a greater incentive to pay the cost to …


Landscape Population And Evolutionary Genomics Of Several Closely Related Species Of Mallard-Like Ducks, Joshua Brown Aug 2021

Landscape Population And Evolutionary Genomics Of Several Closely Related Species Of Mallard-Like Ducks, Joshua Brown

Open Access Theses & Dissertations

Divergence and speciation proceed through three major evolutionary forces (i.e., selection, genetic drift, and gene flow) that are often spatially and temporally heterogeneous across the landscape. Moreover, these forces can have differing but subtle effects within the genomes of diverging taxa, and therefore, disentangling the effects of these evolutionary mechanisms throughout the speciation process can be challenging. Here, I use a recent species radiation, the mallard complex, to investigate how strong, yet varied, evolutionary pressures influence the speciation process. The mallard complex consists of 14 mallard-like waterfowl species around the world that have some of the highest rates of hybridization …


Empathy And Fairness In Nonhuman Primates: Evolutionary Bases Of Human Morality, Colt Halter May 2021

Empathy And Fairness In Nonhuman Primates: Evolutionary Bases Of Human Morality, Colt Halter

Intuition: The BYU Undergraduate Journal of Psychology

Darwin offered an evolutionary perspective on the origins of human morality, suggesting that humans share a biological foundation with nonhuman primates. This paper reviews the current literature on moral and prosocial behaviors of nonhuman primates, specifically examining whether nonhuman primates exhibit behaviors that are typical of empathy and fairness. The literature documents that nonhuman primates exhibit empathetic behaviors regarding emotional contagion and sympathetic concern. There is also evidence that nonhuman primates have a sense of fairness, seen in their reciprocal behaviors and aversion to inequity. Taken together, this suggests that there are evolutionary roots of morality, lending empirical support to …


Chloroplast Genomes In Populus (Salicaceae): Comparisons From An Intensively Sampled Genus Reveal Dynamic Patterns Of Evolution, Jiawei Zhou, Shuo Zhang, Jie Wang, Hongmei Shen, Bin Ai, Wei Gao, Cuijun Zhang, Qili Fei, Daojun Yuan, Zhiqiang Wu, Luke R. Tembrock, Sen Li, Cuiha Gu, Xuezhu Liao May 2021

Chloroplast Genomes In Populus (Salicaceae): Comparisons From An Intensively Sampled Genus Reveal Dynamic Patterns Of Evolution, Jiawei Zhou, Shuo Zhang, Jie Wang, Hongmei Shen, Bin Ai, Wei Gao, Cuijun Zhang, Qili Fei, Daojun Yuan, Zhiqiang Wu, Luke R. Tembrock, Sen Li, Cuiha Gu, Xuezhu Liao

Aspen Bibliography

The chloroplast is one of two organelles containing a separate genome that codes for essential and distinct cellular functions such as photosynthesis. Given the importance of chloroplasts in plant metabolism, the genomic architecture and gene content have been strongly conserved through long periods of time and as such are useful molecular tools for evolutionary inferences. At present, complete chloroplast genomes from over 4000 species have been deposited into publicly accessible databases. Despite the large number of complete chloroplast genomes, comprehensive analyses regarding genome architecture and gene content have not been conducted for many lineages with complete species sampling. In this …


The Role Of Nutrition And Hormone Signaling In Extended Larval Development And Obesity In Starvation-Selected Drosophila Melanogaster, Jennifer M. Clark May 2021

The Role Of Nutrition And Hormone Signaling In Extended Larval Development And Obesity In Starvation-Selected Drosophila Melanogaster, Jennifer M. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Brief periods of starvation are a common stressor that most animals encounter in the wild and must be able to survive in order to maximize their fitness. Starvation resistance of the adult fruit fly, Drosophila melanogaster, is thought to be primarily conferred by adult fat stores, body size, metabolic rate, behavior, and activity levels. Additionally, flies selected for starvation resistance also often show delayed pupariation, which is usually indicative of altered hormone signaling. How starvation selection extends development and if it contributes to adult starvation resistance remains incompletely studied. Identifying the targets of starvation selection that cause extended development and …


Zebrafish (Danio Rerio) Hoxb6: An Exploration Into The Divergence Of Genomic Dna Sequence And Gene Expression Across Teleost Fishes Post-Genome Duplication, Amber Lynn Rittgers, Pierre Le Pabic, Adam Davis Apr 2021

Zebrafish (Danio Rerio) Hoxb6: An Exploration Into The Divergence Of Genomic Dna Sequence And Gene Expression Across Teleost Fishes Post-Genome Duplication, Amber Lynn Rittgers, Pierre Le Pabic, Adam Davis

Georgia Journal of Science

Hoxb6 is an evolutionarily conserved developmental regulatory gene that functions, in part, to pattern several organs and organ systems within the embryonic trunk during vertebrate embryogenesis. The cis-regulatory circuitry mediating trunk expression in mouse (Mus musculus) may be conserved across gnathostome vertebrates, as several other species show similar trunk expression patterns, including chicken (Gallus gallus), dogfish shark (Scyliorhinus canicula), and several teleost fishes. A whole genome duplication event that occurred in the lineage leading to teleost fishes has generated at least two Hoxb6 genes, hoxb6a and b6b. Two teleost fishes of the …


The Phoenix, Fernanda Perez-Alvarez Apr 2021

The Phoenix, Fernanda Perez-Alvarez

Montserrat Annual Writing Prize

This article uses a mythical creature, the phoenix, to examine and illustrate the biological principles for generation of an adult body plan from a single cell. Using the study of developmental biology, it explores the cellular and molecular biology that underpins the massive complexity of creating an adult body plan. It also explores the similarities and differences between different embryos, and how nature and evolution have shaped the biology of those embryos to create different body plans.


The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes Mar 2021

The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes

USF Tampa Graduate Theses and Dissertations

Objectives: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations.

Materials and methods: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy–Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables.

Results: Many of the samples have extremely high frequencies of the T allele (q̄ = 0.62, median = 0.66). In this region, the frequency of the T …


Climate Niche Evolution In C4+Cam Portulaca And Closely Related C3+Cam Lineages, Nora M. Heaphy Jan 2021

Climate Niche Evolution In C4+Cam Portulaca And Closely Related C3+Cam Lineages, Nora M. Heaphy

Library Map Prize

With at least a hundred independent origins among land plants, the CAM and C4 photosynthetic pathways represent one of the most notable examples of global convergent evolution of a complex trait. While biochemically similar, CAM and C4 are generally understood to be two distinct ecological adaptations evolving along separate trajectories. However, the purslanes (Portulaca), a globally widespread clade of around 100 species of annual and perennial succulents, are able to operate both CAM and C4 cycles in the same leaf. Portulaca likely originated from a facultative CAM ancestor and then evolved a C4 system at least three times …


Larval Anatomy Of Monotypic Painted Ant Nest Frogs Lithodytes Lineatus Reveals Putative Homoplasies With The Leptodactylus Pentadactylus Group (Anura: Leptodactylidae), Filipe A.C Do Nascimento, Rafael O. De Sá, Paulo C. De A. Garcia Jan 2021

Larval Anatomy Of Monotypic Painted Ant Nest Frogs Lithodytes Lineatus Reveals Putative Homoplasies With The Leptodactylus Pentadactylus Group (Anura: Leptodactylidae), Filipe A.C Do Nascimento, Rafael O. De Sá, Paulo C. De A. Garcia

Biology Faculty Publications

The morphological diversity of anuran larvae made them an important source of information for evolutionary and systematic studies. For the monotypic frog genus Lithodytes, which has an interesting taxonomic history, including its past synonymizing with Adenomera and its placement as a subgenus of Leptodactylus, the information provided from its larvae can help to understand its systematics interrelationships and also provide insights about its evolutionary trajectories. Herein, we provide a detailed description of the larval morphology of Lithodytes lineatus, including novel data of internal morphology (buccopharyngeal cavity and skeleton), and discuss some morphological and evolutionary aspects in relation …


Population Genomic Transformations Induced By Isolation Of Wild Bird Avian Influenza Viruses (Orthomyxoviridae) In Embryonated Chicken Eggs, Matthew W. Hopken, Antoinette J. Piaggio, K. L. Pabilonia, James Pierce, Theodore Anderson, Courtney Pierce, Zaid Abdo Jan 2021

Population Genomic Transformations Induced By Isolation Of Wild Bird Avian Influenza Viruses (Orthomyxoviridae) In Embryonated Chicken Eggs, Matthew W. Hopken, Antoinette J. Piaggio, K. L. Pabilonia, James Pierce, Theodore Anderson, Courtney Pierce, Zaid Abdo

USDA Wildlife Services: Staff Publications

Isolation and cultivation of wild-type viruses in model organism cells or tissues is standard practice in virology. Oftentimes, the virus host species is distantly related to the species from which the culture system was developed. Thus, virus culture in these tissues and cells basically constitutes a host jump, which can lead to genomic changes through genetic drift and/or adaptation to the culture system. We directly sequenced 70 avian influenza virus (Orthomyxoviridae) genomes from oropharyngeal/cloacal swabs collected from wild bird species and paired virus isolates propagated from the same samples following isolation in specific-pathogen-free embryonated chicken eggs. The data were analyzed …


Functional Genetic Approaches To Provide Evidence For The Role Of Toolkit Genes In The Evolution Of Complex Color Patterns In Drosophila Guttifera, Mujeeb Olushola Shittu Jan 2021

Functional Genetic Approaches To Provide Evidence For The Role Of Toolkit Genes In The Evolution Of Complex Color Patterns In Drosophila Guttifera, Mujeeb Olushola Shittu

Dissertations, Master's Theses and Master's Reports

Toolkit genes are set of genes that orchestrate the development of basic body plan of animals, and they are highly conserved in all animals. The co-option of the toolkit genes into the pigmentation pathway has led to the evolution of novel species. This study focuses on understanding how the complex color patterns in animals develop by using the Drosophila species in the quinaria group as models. We developed an mRNA in situ hybridization (ISH) protocol, which allowed us to study gene expression patterns in the abdomen of developing pupae of non-model Drosophila species (Chapter 2). Through ISH, we found that …


The Evolution Of Technology, Kelly Cooper Jan 2021

The Evolution Of Technology, Kelly Cooper

Williams Honors College, Honors Research Projects

As per outlined by Dr. Quinn, this literature review will be a comprehensive review paper including an overview of current and previous research done in the field of Memetics. This will further include sifting through literature to hone in on a specific, new area of memetics Dr. Weeks is focused on, the evolutionary change of abiotic factors through purchasing. This is to be completed with the help of the library worshops designed to teach the skills necessary to undergo a literature review of this size. I will also participate in weekly reading groups to discuss papers and work closely with …


Morphological Variance In Mouthparts And Foraging Behavior In Bumblebees, Ye Jin Lee Jan 2021

Morphological Variance In Mouthparts And Foraging Behavior In Bumblebees, Ye Jin Lee

Honors Theses

Bumblebees (Hymenoptera: Apidae: Bombus) show an incredible degree of size variation within and between species. Individuals from the same hive may vary up to 10-fold in mass. This variation allows individuals to specialize in foraging on different flowers suited to their morphology. However, as different species have different foraging behaviors, their variation in mouthparts and scaling of mouthparts to body size may have been under different kinds of stabilizing selection as they adapted to collect nectar from flowering plants over evolutionary time. Here, we examined the scaling relationships between body size and mouthpart structures, and the variation in mouthpart shape …


Exploring Zosterophyll Relationships Within A More Broadly Sampled Character Space: A Focus On Anatomy, Megan Nibbelink Jan 2021

Exploring Zosterophyll Relationships Within A More Broadly Sampled Character Space: A Focus On Anatomy, Megan Nibbelink

Cal Poly Humboldt theses and projects

Important constituents of Siluro-Devonian floras, zosterophylls gave rise to the lycophytes. I explore the relationships of 18 zosterophyll species from 16 genera, maximizing sampling of anatomy. Using phylogenetic and phenetic methods, I (1) assess the influence of tree rooting, taxon sampling, and morphological vs anatomical characters on the stability of relationships; and (2) compare phylogenetic and phenetic methods in terms of relationships recovered. Phenetic analyses show sensitivity to taxon sampling and support placement of Renalia among zosterophylls, but do not provide results that are strongly congruent with those of phylogenetic analyses. Phylogenetic analyses demonstrate that taxon and character sampling significantly …


Lifetime Reproductive Benefits Of Cooperative Polygamy Vary For Males And Females In The Acorn Woodpecker (Melanerpes Formicivorus), Sahas Barve, Christina Riehl, Eric L. Walters, Joseph Haydock, Hannah L. Dugdale, Walter D. Koenig Jan 2021

Lifetime Reproductive Benefits Of Cooperative Polygamy Vary For Males And Females In The Acorn Woodpecker (Melanerpes Formicivorus), Sahas Barve, Christina Riehl, Eric L. Walters, Joseph Haydock, Hannah L. Dugdale, Walter D. Koenig

Biological Sciences Faculty Publications

Cooperative breeding strategies lead to short-term direct fitness losses when individuals forfeit or share reproduction. The direct fitness benefits of cooperative strategies are often delayed and difficult to quantify, requiring data on lifetime reproduction. Here, we use a longitudinal dataset to examine the lifetime reproductive success of cooperative polygamy in acorn woodpeckers (Melanerpes formicivorus), which nest as lone pairs or share reproduction with same-sex cobreeders. We found that males and females produced fewer young per successful nesting attempt when sharing reproduction. However, males nesting in duos and trios had longer reproductive lifespans, more lifetime nesting attempts and higher …