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Cognitive Ecology Of Color Vision In Orchid Bees, Andreia Queiroz Santos A Figueiredo Nov 2021

Cognitive Ecology Of Color Vision In Orchid Bees, Andreia Queiroz Santos A Figueiredo

Dissertations

Animals interact with their environment and acquire information from it. Information can be processed by their sensory systems and influence behavior, often mediated through mechanisms of decision-making and learning. Animal pollinators acquire information from flowers and use this information to make decisions about the flowers they visit. My research aimed to understand the role of color vision in a tropical pollinator, the orchid bee Euglossa dilemma. Chapter 1 is a review exploring pollination through the lens of prepared learning. Prepared learning proposes that animals learn some associations better than others due to an evolved match with the environment. I …


Illustrated Guide To The Immature Lepidoptera On Oaks In Missouri, Robert Marquis, Steven Passoa, John Lill, James Whitfield, Josiane Le Corff, Rebecca Forkner, Valerie Passoa Jun 2019

Illustrated Guide To The Immature Lepidoptera On Oaks In Missouri, Robert Marquis, Steven Passoa, John Lill, James Whitfield, Josiane Le Corff, Rebecca Forkner, Valerie Passoa

Biology Department Faculty Works

Oak trees (Quercus spp.) dominate many forests in North America, and their diverse herbivore fauna is a major component of ecological biodiversity. Yet, identification guides for oak-feeding Lepidoptera in the eastern United States usually lack detailed larval morphological characteristics and pupal descriptions. This book describes the immature stages of common species of butterflies and moths (Lepidoptera) whose larvae are found on 10 species of oak (Quercus) in the eastern Missouri Ozarks (USA). Data were collected mainly as part of the Missouri Ozark Forest Ecosystem Project (MOFEP), a longterm study of the effects of harvesting regimes on forest structure and function. …


Mode And Rate Of Evolution Of Haemosporidian Mitochondrial Genomes: Timing The Radiation Of Avian Parasites, Patricia Parker, M Pacheco, Nubia Matta, Gediminas Valkiūnas, Beatriz Mello, Craig Stanley, Miguel Lentino, Maria Garcia-Amado, Michael Cranfield, Sergei Pond, Ananias Escalante Feb 2018

Mode And Rate Of Evolution Of Haemosporidian Mitochondrial Genomes: Timing The Radiation Of Avian Parasites, Patricia Parker, M Pacheco, Nubia Matta, Gediminas Valkiūnas, Beatriz Mello, Craig Stanley, Miguel Lentino, Maria Garcia-Amado, Michael Cranfield, Sergei Pond, Ananias Escalante

Biology Department Faculty Works

Haemosporidians are a diverse group of vector-borne parasitic protozoa that includes the agents of human malaria; however, most of the described species are found in birds and reptiles. Although our understanding of these parasites’ diversity has expanded by analyses of their mitochondrial genes, there is limited information on these genes’ evolutionary rates. Here, 114 mitochondrial genomes (mtDNA) were studied from species belonging to four genera: Leucocytozoon, Haemoproteus, Hepatocystis, and Plasmodium. Contrary to previous assertions, the mtDNA is phylogenetically informative. The inferred phylogeny showed that, like the genus Plasmodium, the Leucocytozoon and Haemoproteus genera are not monophyletic groups. Although sensitive to …


Oxidative Stress In Avian Embyros, Toshi Tsunekage Dec 2015

Oxidative Stress In Avian Embyros, Toshi Tsunekage

Dissertations

Oxidative stress has been implicated in mediating trade-offs in the evolution of life histories. Oxidative stress results from an imbalance in the production of free radicals and an organism’s antioxidant defenses. Higher metabolic rates associated with more rapid growth and shorter development periods may increase oxidative stress and accumulated cellular damage in embryonic tissues. In my dissertation I explored oxidative stress and antioxidant defenses in avian embryos. I measured levels of oxidative stress in tissues of different stage embryos of Japanese quail (Coturnix japonica), and tested if patterns of lipid peroxidation could be explained by changes in the developing embryo’s …


Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart May 2015

Climate-Driven Change In Himalayan Rhododendron Phenology, Robert Evan Hart

Dissertations

Phenology – the seasonal timing of life-history events – is a critical dimension of natural history. It is also one of the earliest and most noticeable traits by which organisms respond to climate change. However, these responses are complex, and only beginning to be understood, especially in the montane and alpine environments that are among the ecosystems most vulnerable to climate change. Drawing from diverse data sets and employing multiple methodologies, I examined how climate affects phenology in Himalayan Rhododendron spp. Comprehensively monitoring flowering phenology over gradients of season and elevation on Mt. Yulong, China – home to a diverse …


Evolution And Ecology Of Two Iconic Australian Clades: The Meliphagidae (Birds) And The Hakeinae (Plants), Eliot Trimarchi Miller Jan 2015

Evolution And Ecology Of Two Iconic Australian Clades: The Meliphagidae (Birds) And The Hakeinae (Plants), Eliot Trimarchi Miller

Dissertations

The first part of this dissertation explores the evolution of two iconic groups of species through Australian climate space: the Meliphagidae, or honeyeaters, which are primarily nectar-feeding birds, and the Hakeinae, a section of the plant family Proteaceae. Both groups are inferred to have had their origins in Gondwanan rainforests that were widespread across Australia 45 million years ago and then diversified into more arid environments as the continent’s climate became more arid. Accordingly, dry environments are inhabited by closely related (phylogenetically clustered) sets of species, although, in contrast to the honeyeaters, Hakeinae communities are characterized by more localized diversification. …


Reinterpreting Bateman Gradients: Multiple Mating And Selection In Both Sexes Of A Songbird Species, N.M. Gerlach, J.W Mcglothlin, P.G Parker, E.D Ketterson Sep 2012

Reinterpreting Bateman Gradients: Multiple Mating And Selection In Both Sexes Of A Songbird Species, N.M. Gerlach, J.W Mcglothlin, P.G Parker, E.D Ketterson

Biology Department Faculty Works

Bateman’s principle, which states that male reproductive success should increase with multiple mating, whereas female reproductive success should not, has long been used to explain sex differences in behavior. The statistical relationship between mating success and reproductive success, or Bateman gradient, has been proposed as a way to quantify sex differences in sexual selection. We used a long-term data set on the distribution of paternity in the socially monogamous dark-eyed junco to examine the effect of multiple mating on lifetime reproductive success and to determine the relative contributions of within-pair and extra-pair mating. Both sexes exhibited a strong positive Bateman …


Community Ecology And Phylogeography Of Bird Assemblages In Arid Zones Of Northern Venezuela: Implications For The Conservation Of Restricted-Range Birds, Adriana Rodriguez-Ferraro Jul 2008

Community Ecology And Phylogeography Of Bird Assemblages In Arid Zones Of Northern Venezuela: Implications For The Conservation Of Restricted-Range Birds, Adriana Rodriguez-Ferraro

Dissertations

Aridlands of northern Venezuela are important from an ornithological perspective because of the occurrence of habitat specialist birds that depend exclusively on desert scrubs and are endemic to this region. Currently, long-term survival of habitat specialists is threatened by ongoing changes in vegetation but the effects of such changes on bird assemblages are unknown. The goal of this study was to characterize bird assemblages found in six arid zones in northern Venezuela at both ecological and genetic levels, and to generate information relevant for conservation planning. The study involved assessments of patterns of avian species richness, abundance, community composition and …


Comparative Immune Function In Wild Birds, Kevin David Matson May 2007

Comparative Immune Function In Wild Birds, Kevin David Matson

Dissertations

Over the last several decades, interest in quantifying immune function in comparative studies of wild animals has grown appreciably. Now, the field of ecological immunology is undergoing a transition, and ¿second generation¿ studies are being designed and carried out. With a greater appreciation of the complexity of immune systems, these second generation studies are commonly distinguished from their antecedents by making comparisons using multiple assays and including multiple species. I worked to advance this transition by developing novel approaches to comparative immunology, exploring the interrelationships among indices of immune function, and applying multiple indices to a question of comparative avian …


The Role Of Local And Regional Factors In The Foraging Ecology Of Birds Associated With Polylepis Woodlands, Grace Patricia Servat-Valenzuela May 2007

The Role Of Local And Regional Factors In The Foraging Ecology Of Birds Associated With Polylepis Woodlands, Grace Patricia Servat-Valenzuela

Dissertations

Understanding the extent to which patterns of functional structure are repeated in space and the scale at which different factors (local and regional) operate to explain community patterns are of important in community ecology. I studied the extent of spatial variation in foraging ecology of birds in the Polylepis community, a vegetation system of the Andes, in regard to variation in local (vegetation structure, floristic composition, food resources) and regional factors (biogeography). Specifically, I studied foraging ecology of nine insectivorous bird species (and the assemblage they conform) across twelve disjunct woodlands embedded in three biogeographic regions of the Peruvian Andes. …


Evolutionary Epidemiology Of Endemic Gal¿Pagos Birds And Their Parasites, Noah Kerness Whiteman May 2006

Evolutionary Epidemiology Of Endemic Gal¿Pagos Birds And Their Parasites, Noah Kerness Whiteman

Dissertations

In order to better understand parasite diversification, I went to the Gal¿pagos Islands to study the ecology and evolution of a model bird-parasite system, which included four phylogenetically independent ectoparasite lineages infecting the Gal¿pagos Hawk (Aves: Buteo galapagoensis). The parasites comprised two lice (Insecta: Phthiraptera: Amblycera, Ischnocera), a lousefly (Diptera: Hippoboscidae) and an avian skin mite (Acari: Epidermoptidae). Ultimately, my goal was to examine ectoparasite evolutionary epidemiology and disease susceptibility in relation to the host¿s ecological and colonization history. At the outset, I hypothesized that parasite natural history was key in influencing the coalescent process. Accordingly, I found differences …


Conservation Medicine On The Galápagos Islands: Partnerships Among Behavioral, Population, And Veterinary Scientists, Patricia Parker, Noah Whiteman, R. Miller Jan 2006

Conservation Medicine On The Galápagos Islands: Partnerships Among Behavioral, Population, And Veterinary Scientists, Patricia Parker, Noah Whiteman, R. Miller

Biology Department Faculty Works

No abstract provided.


Correlational Selection Leads To Genetic Integration Of Body Size And An Attractive Plumage Trait In Dark-Eyed Juncos, Joel Mcglothlin, Patricia Parker, Val Nolan, Ellen Ketterson Jan 2005

Correlational Selection Leads To Genetic Integration Of Body Size And An Attractive Plumage Trait In Dark-Eyed Juncos, Joel Mcglothlin, Patricia Parker, Val Nolan, Ellen Ketterson

Biology Department Faculty Works

When a trait's effect on fitness depends on its interaction with other traits, the resultant selection is correlational and may lead to the integration of functionally related traits. In relation to sexual selection, when an ornamental trait interacts with phenotypic quality to determine mating success, correlational sexual selection should generate genetic correlations between the ornament and quality, leading to the evolution of honest signals. Despite its potential importance in the evolution of signal honesty, correlational sexual selection has rarely been measured in natural populations. In the dark‐eyed junco (Junco hyemalis), males with experimentally elevated values of a plumage trait (whiteness …