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Articles 61 - 90 of 156
Full-Text Articles in Other Ecology and Evolutionary Biology
Are Capuchin Monkeys (Sapajus Spp.) Sensitive To Lost Opportunities? The Role Of Opportunity Costs In Intertemporal Choice, Elsa Addessi, Valeria Tierno, Valentina Focaroli, Federica Rossi, Serena Gastaldi, Francesca De Petrillo, Fabio Paglieri, Jeffrey R. Stevens
Are Capuchin Monkeys (Sapajus Spp.) Sensitive To Lost Opportunities? The Role Of Opportunity Costs In Intertemporal Choice, Elsa Addessi, Valeria Tierno, Valentina Focaroli, Federica Rossi, Serena Gastaldi, Francesca De Petrillo, Fabio Paglieri, Jeffrey R. Stevens
Jeffrey Stevens Publications
Principles of economics predict that the costs associated with obtaining rewards can influence choice. When individuals face choices between a smaller, immediate option and a larger, later option, they often experience opportunity costs associated with waiting for delayed rewards because they must forego the opportunity to make other choices. We evaluated how reducing opportunity costs affects delay tolerance in capuchin monkeys. After choosing the larger option, in the High cost condition, subjects had to wait for the delay to expire, whereas in the Low cost different and Low cost same conditions, they could perform a new choice during the delay. …
A Desert Tortoise–Common Raven Viable Conflict Threshold, Kerry L. Holcomb, Peter S. Coates, Brian G. Prochazka, Timothy Shields, William I. Boarman
A Desert Tortoise–Common Raven Viable Conflict Threshold, Kerry L. Holcomb, Peter S. Coates, Brian G. Prochazka, Timothy Shields, William I. Boarman
Human–Wildlife Interactions
Since 1966, common raven (Corvus corax; raven) abundance has increased throughout much of this species’ Holarctic distribution, fueled by an ever-expanding supply of anthropogenic resource subsidies (e.g., water, food, shelter, and nesting substrate) to ecoregion specific raven population carrying capacities. Consequently, ravens are implicated in declines of both avian and reptilian species of conservation concern, including the California (USA) endangered and federally threatened Mojave desert tortoise (Gopherus agassizii; desert tortoise). While ravens are a natural predator of desert tortoises, the inter-generational stability of desert tortoise populations is expected to be compromised as annual juvenile survival is …
Introduction To Neutrosophic Genetics, Florentin Smarandache
Introduction To Neutrosophic Genetics, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
Neutrosophic Genetics is the study of genetics using neutrosophic logic, set, probability, statistics, measure and other neutrosophic tools and procedures. In this paper, based on the Neutrosophic Theory of Evolution (that includes degrees of Evolution, Neutrality (or Indeterminacy), and Involution) – as extension of Darwin’s Theory of Evolution, we show the applicability of neutrosophy in genetics, and we present within the frame of neutrosophic genetics the following concepts: neutrosophic mutation, neutrosophic speciation, and neutrosophic coevolution.
Ecology And Evolution, David J. Lohman
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.
Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso
Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso
LSU New Orleans Theses and Dissertations
One of the most important gene families to play a role in adaptive immunity is the major histocompatibility complex (MHC). MHC class II loci are considered to be the most variable loci in the vertebrate genome, and studies have shown that this variability can be maintained through complex co-evolutionary dynamics between host and parasite. Despite the rich body of research into the MHC, there is comparatively little understanding of its genomic architecture in reptiles. Similarly, loci associated with innate immunity have received little attention in reptiles compared to other vertebrates. In the first chapter, we investigated the structure and organization …
Evolutionary Ecology Of Host-Parasite Relationships: Role Of Host Ecology, Phylogeny, And Demographics In Shaping Parasite Evolution, Erika Taylor Gendron
Evolutionary Ecology Of Host-Parasite Relationships: Role Of Host Ecology, Phylogeny, And Demographics In Shaping Parasite Evolution, Erika Taylor Gendron
Biology ETDs
Host-parasite systems exist across complex and ecologically heterogeneous landscapes, and may occur across taxonomically and ecologically disparate host species. Under these conditions, mechanisms underlying microevolutionary processes (i.e. gene flow, genetic drift) are not always clear, and may be mediated by numerous co-occurring factors specific to individual hosts. Host traits such as host immunology, demographics, phylogeny and ecology may act in concert to shape host-parasite relationships, and ultimately evolutionary processes. The research described herein used phylogeographic, phylogenomic, and population genetic methods to further understanding of how host traits impact the evolutionary ecology of trematode systems, using avian schistosomes (Digenea: Schistosomatidae) as …
Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer
Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer
Poisonous Plant Research (PPR)
Locoweeds are the most widespread poisonous plant problem in the world and have been reported in the Western United States since the 1800s, causing tremendous losses in livestock. Consumption of locoweeds by grazing animals stimulates the neurological disease, locoism, characterized by weight loss, ataxia, and lack of muscular coordination. The name locoweed is used for Astragalus and Oxytropis species known to contain swainsonine, the toxic principle produced by the plant endophytic fungus Undifilum. Astragalus includes 2,500-3,000 species and many varieties that have almost identical morphological characteristics that overlap among species, leading to improper identification. Therefore, the aim of this study …
Martin Luther King Jr. And Ernest Everett Just - On Evolution Of Ethical Behavior, Theodore Walker
Martin Luther King Jr. And Ernest Everett Just - On Evolution Of Ethical Behavior, Theodore Walker
Perkins Faculty Research and Special Events
Rev. Martin Luther King Jr. prescribed an evolutionary advance in ethical behavior: the total “abolition of poverty” and the abolition of war throughout “the world house.” Cell biologist Ernest Everett Just advanced the idea that human ethical behavior evolved from cellular origins.
Also, astrobiologists Chandra Wickramasinghe and Sir Fred Hoyle advanced the idea of cosmic biology, including stellar evolution and cosmic evolution. From cells to humans to stars and cosmology, evolutionary natural science converges with natural theology.
The Bioethical Significance Of “The Origin Of Man’S Ethical Behavior” (October 1941, Unpublished) By Ernest Everett Just And Hedwig Anna Schnetzler Just, Theodore Walker Jr.
The Bioethical Significance Of “The Origin Of Man’S Ethical Behavior” (October 1941, Unpublished) By Ernest Everett Just And Hedwig Anna Schnetzler Just, Theodore Walker Jr.
Journal of the South Carolina Academy of Science
Abstract –
E. E. Just (1883-1941) is an acknowledged “pioneer” in cell biology, and he is perhaps the pioneer in study of egg cell fertilization. Here we discover that Just also made pioneering contributions to general biology and evolutionary bioethics.
Within Just’s published contributions to observational cell biology, there are substantial fragments of his theory of ethical behavior, a theory with roots in cell biology. In addition to such previously available fragments, Just’s fully developed theory is now available. This recently discovered unpublished book-length manuscript argues for the biological origins of ethical behavior (evolving from cells to humans, within a …
Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson
Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson
College of Graduate Studies: Theses & Dissertations
Studying warning coloration and mimicry is an effective way to understand predator-driven selection and phenotypic diversity. The presence (sympatry) or absence (allopatry) of a toxic model plays a role in shaping mimetic phenotypes. However, the impact of edge sympatry and allopatry on predation of mimetic phenotypes is not well understood. We studied coralsnake mimicry to test how edge sympatry and allopatry affect predation on mimetic phenotypes. Specifically, we tested 1) if overall attack rates varied with edge sympatry of coralsnakes 2) which color patterns conferred a fitness advantage 3) which specific mimetic signal components are important in driving predatory attacks …
The Evolution And Development Of Chiropteran Flight, Emmaline Willis
The Evolution And Development Of Chiropteran Flight, Emmaline Willis
Honors Theses and Capstones
No abstract provided.
The Evolution Of Dragons, Laura J. Mayfield
The Evolution Of Dragons, Laura J. Mayfield
Undergraduate Theses, Professional Papers, and Capstone Artifacts
Dragons have been depicted in human art as early as 4500 BCE. For centuries, these fantasy creatures have inspired countless folk and fantasy tales, as well as appearing in the art of different cultures around the world. Now there are thousands of different depictions of these huge, flying, fire-breathing lizards, but are any of them possible? In this study, I reference peer-reviewed scientific articles, phylogenetic analysis, and paleoart studies to create biologically-sound dragons. Basing the dragon lineage on a real branch of webbed-winged scansoriopterygids—an extinct family of climbing and gliding maniraptoran dinosaurs—I explored the possible wing-structure, fire-breathing abilities, and effects …
Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso
Plasticity And The Impact Of Increasing Temperature On A Tropical Ectotherm, Adam A. Rosso
College of Graduate Studies: Theses & Dissertations
Organisms may respond to climate change through behavior, genetic adaptation, and/or phenotypic plasticity. Tropical ectotherms are thought to be especially vulnerable to climate change because most have a narrow range of thermal tolerance while living close to their upper thermal tolerance limits. Additionally, many tropical species live in closed-canopy forests, which provide homogenous thermal landscapes that prevent behavioral compensation for stressfully warm temperatures. Finally, tropical ectotherms are thought to have decreased capacity for phenotypic plasticity because they have evolved in thermally stable environments. We tested gene expression patterns and phenotypic plasticity in the Panamanian slender anole by a) measuring changes …
Effects Of Insect Opportunists On A Four-Level Trophobiotic System Involving Nectar-Producing Galls Of The Cynipid Wasp Disholcaspis Quercusmamma (Hymenoptera: Cynipidae), Stephanie L. Smith
Effects Of Insect Opportunists On A Four-Level Trophobiotic System Involving Nectar-Producing Galls Of The Cynipid Wasp Disholcaspis Quercusmamma (Hymenoptera: Cynipidae), Stephanie L. Smith
Masters Theses
The induction of plant galls is considered an adaptive life history trait found in many insect groups. The formation of galls provides several advantages to the gall maker, such as enhanced nutrition, favorable microclimate, and protection from natural enemies, including parasitoids, inquilines, and predators. Order Hymenoptera has many gall-making species, belonging to the gall wasp family Cynipidae. As an extended phenotype of the gall makers, some galls exhibit very sophisticated adaptive mechanisms involving multilevel species interactions. In particular, the oak galls of the Cynipid species Disholcaspis quercusmamma, found in much of Illinois, produce a palatable, sugary nectar-like secretion, attracting …
Evidence Of Local Adaptation To Climate In An Invasive Ectotherm: A Study On The Eurasian Gypsy Moth (Lymantria Dispar) In North America, Phillip M. Gibbs
Evidence Of Local Adaptation To Climate In An Invasive Ectotherm: A Study On The Eurasian Gypsy Moth (Lymantria Dispar) In North America, Phillip M. Gibbs
Theses and Dissertations
Invasive species exist in nearly every ecosystem both terrestrial and aquatic. Improving our understanding of the mechanisms that shape the ability of these organisms to physiologically cope with their surroundings will be crucial to preparing for future impacts of climate change. The Gypsy Moth (Lymantria dispar) has been expanding its range across North America over the last 100+ years since its arrival in Medford, Massachusetts. This study quantifies upper thermal limits (UTL) across 8 different populations of L. dispar in North America and seeks to determine if signals of local adaptation to climate across a latitudinal gradient may …
Can Zooplankton On The North American Great Plains ‘Keep Up’ With Climate-Driven Salinity Change?, Mariam Elmarsafy
Can Zooplankton On The North American Great Plains ‘Keep Up’ With Climate-Driven Salinity Change?, Mariam Elmarsafy
Theses and Dissertations (Comprehensive)
The Great Plains of North America are projected to become more arid as the climate changes over the next century. Salinity levels for lakes in this region are linked to climate, suggesting that lakes will become more saline as the climate becomes drier. One group of organisms that might be affected by increased salinity levels are the zooplankton, aquatic invertebrates that transfer energy from primary producers to macroinvertebrates and fish. Little is known about the ability of zooplankton to adapt to long-term increases in lake salinity levels. For my thesis, I used resurrection ecology to examine how a common zooplankter, …
Conflicts And Triage, Kate E. Lynch, Daniel T. Blumstein
Conflicts And Triage, Kate E. Lynch, Daniel T. Blumstein
Animal Sentience
To represent diverse interests successfully, a strategy for dealing with conflicts is needed. We discuss an approach to maximizing the interests of the greatest number of individuals, present and future.
Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey R. Gadek
Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey R. Gadek
Biology ETDs
The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …
The Evolution Of Spinosad Resistance In Colorado Potato Beetles (Leptinotarsa Decemlineata), Coby Michael Klein
The Evolution Of Spinosad Resistance In Colorado Potato Beetles (Leptinotarsa Decemlineata), Coby Michael Klein
Dissertations, Theses, and Capstone Projects
Colorado potato beetles (Leptinotarsa decemlineata) are a major pest of cultivated potato plants worldwide. They are well-known for their ability to rapidly evolve resistance to all major classes of pesticides. Defoliation of potato plants by L. decemlineata can reduce potato yields by a considerable margin. The damage done by resistant beetles is steep and much research is focused on developing new chemical controls, especially those derived from naturally occurring compounds. Spinosad is a relatively new natural product insecticide, introduced approximately a decade ago, suitable for use in organic farming. Potato beetles on Long Island, NY developed very strong …
The ‘Law Of Environmental Dependence’ - Biology And Ethics In The Work Of Ernest Everett Just: + Found – Some 251 Mostly Typed Pages, Theodore Walker
The ‘Law Of Environmental Dependence’ - Biology And Ethics In The Work Of Ernest Everett Just: + Found – Some 251 Mostly Typed Pages, Theodore Walker
Perkins Faculty Research and Special Events
Abstract-
“The Origin of Man’s Ethical Behavior” (circa October 1941) by Ernest Everett Just and Hedwig A. Schnetzler Just - is an unpublished book manuscript about the biological origins and evolution of ethical behavior, and about “the law of environmental dependence.” Missing since Just’s death in October 1941, it was found and identified in May 2018 among the collected papers of Ernest Everett Just preserved at the Howard University Moorland-Spingarn Research Center in Washington, DC. In addition to the 1996 US postage with the caption “Ernest E. Just, Biologist,” we now have reason to add two new postage stamps with …
Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner
Electronic Theses and Dissertations
North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) …
Phylogenetic History Of The Amy Gene Cluster In Catarrhines, Christian M. Gagnon
Phylogenetic History Of The Amy Gene Cluster In Catarrhines, Christian M. Gagnon
Theses and Dissertations
This study phylogenetically analyzed 30 AMY-related genes from 11 primates. The results show the gradual expansion of the AMY gene family which could have allowed primates to adapt to various ecological landscapes and maximize energy intake from starch-rich foods in periods of food scarcity.
Cichlid Size Vs Flow Rate, Amy E. Naumovski
Cichlid Size Vs Flow Rate, Amy E. Naumovski
STAR Program Research Presentations
Cichlids are a diverse group of fish that are known for their prenatal and postnatal care of their eggs and frys (baby fish). This unique characteristic creates a limitation on the amount of eggs a cichlid can lay and protect, which is particulalry effected by the size of the eggs. Cichlids have a large variance in their egg size, which correlates to a large variance in their fry size. This project explores the trade offs cichlids make in egg size and fry size by specifically testing the ability of varying sized cichlids to swim in different flow rates. This could …
Trade-Offs Shape Carotenoid-Based Color Variation In Redheaded Pine Sawfly (Neodiprion Lecontei) Larvae, Maranda Gaines
Trade-Offs Shape Carotenoid-Based Color Variation In Redheaded Pine Sawfly (Neodiprion Lecontei) Larvae, Maranda Gaines
Lewis Honors College Capstone Collection
Carotenoids serve various ecological roles in animals including coloration, immune responses, and vision. Carotenoid-derived coloration is greatly emphasized in the literature, particularly relating to mate choice and aposematic warning. However, the trade-offs between the color and non-color functions of carotenoids are not thoroughly explored. In the redheaded pine sawfly (Neodiprion lecontei), some larval populations have yellow pigmentation, using carotenoids derived from their diets for aposematic warning coloration. Other larval populations are white in color, having genetically lost the ability to produce the yellow pigment. Because carotenoids are essential to life functions in both the yellow and white populations, we aim …
Symbiotic Bacteria Can Colonize Closely-Related, But Not Distantly-Related Species Of Its Host Dictyostelium Discoideum, Rory Vu Mather
Symbiotic Bacteria Can Colonize Closely-Related, But Not Distantly-Related Species Of Its Host Dictyostelium Discoideum, Rory Vu Mather
Undergraduate Research Symposium Posters
Some of the closest interactions between organisms can be found within symbioses, where different individuals live in close physiological contact and either benefit or harm the other. A powerful kind of benefit comes when bacterial symbionts produce amino acids or provide digestive capabilities outside the host’s ability, in essence taking advantage of the other’s genetic catalog. One such symbiosis is that of the social amoeba Dictyostelium discoideum and its bacterial symbionts Burkholderia agricolaris, Burkholderia hayleyella, and Burkholderia bonneia. In this symbiosis, Burkholderia provide the capability of carrying food bacteria to their host, an advantageous trait when bacterial food is rare. …
Life History Of The Coastal Tailed Frog (Ascaphus Truei) Across An Elevational Gradient, Adrian Daniel Macedo
Life History Of The Coastal Tailed Frog (Ascaphus Truei) Across An Elevational Gradient, Adrian Daniel Macedo
Cal Poly Humboldt theses and projects
The life history of a species is described in terms of its growth, longevity, and reproduction. Unsurprisingly, life history traits are known to vary in many taxa across environmental gradients. In the case of amphibians, species at high elevations and latitudes tend to have shorter breeding seasons, shorter activity periods, longer larval periods, reach sexual maturity at older ages, and produce fewer and larger clutches per year.
The Coastal Tailed Frog (Ascaphus truei) is an ideal species for the study of geographic variation in life history because it ranges across most of the Pacific Northwest from northern California …
Transgenerational Plasticity Is Sex-Dependent And Persistent In Yellow Moneyflower (Mimulus Guttatus), Kayla Akkerman
Transgenerational Plasticity Is Sex-Dependent And Persistent In Yellow Moneyflower (Mimulus Guttatus), Kayla Akkerman
All Master's Theses
Transgenerational phenotypic plasticity, whereby environmental cues experienced by parents alter the phenotype of their progeny, has now been documented in diverse organisms. Transmission of environmentally determined responses is known to occur through both maternal and paternal gametes, but the underlying mechanisms have rarely been compared. In addition, the persistence of induction over multiple generations appears to vary widely but has been characterized for relatively few systems. Yellow monkeyflower (Mimulus guttatus) is known to exhibit transgenerational induction of increased glandular trichome production in response to simulated insect damage. Here we test for differences between maternal and paternal transmission of …
Shaping The Tools Of Battle : Sexual Selection, Contest Dynamics, And Weapon Divergence In The Asian Rhinoceros Beetle Trypoxylus Dichotomus, Jillian F. Del Sol
Shaping The Tools Of Battle : Sexual Selection, Contest Dynamics, And Weapon Divergence In The Asian Rhinoceros Beetle Trypoxylus Dichotomus, Jillian F. Del Sol
Graduate Student Theses, Dissertations, & Professional Papers
Exaggerated weapons of sexual selection often diverge more rapidly and dramatically than other body parts, suggesting that relevant agents of selection may be discernible in contemporary populations. I examined the ecology, reproductive behavior, and strength of sexual selection on horn length in five recently diverged beetle populations that differ in relative horn size. I show that mating system ecology differs between these locations and corresponds with the local strength of contemporary selection on horn length. Comparisons of ecological conditions and selection strength across populations offer a critical first step towards meaningfully linking mating system dynamics, selection patterns, and diversity in …
Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney Iv
Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney Iv
Theses and Dissertations
Emplectonema gracile (Johnston 1837) is a hoplonemertean of marine intertidal hard-bottom communities and is distributed throughout the Northern Hemisphere. Although possessing a planktonic larval stage in its life history, the range of such cosmopolitan marine invertebrate species is often explained by cryptic speciation and anthropogenic transport. The purpose of this study is to test for possible cryptic species using mtDNA markers (COI and 16S rDNA) and to investigate population structure in E. gracile over a portion of its geographic range using mtDNA markers and ddRADseq nuclear SNP data. The results of both phylogenetic- and tree-based species delimitation revealed that E. …
A Change In Grain? Diet Induced Plasticity In The Generalist Grasshopper Melanoplus Differentialis, Austin M. Culotta
A Change In Grain? Diet Induced Plasticity In The Generalist Grasshopper Melanoplus Differentialis, Austin M. Culotta
LSU New Orleans Theses and Dissertations
Phenotypic plasticity is favored in heterogeneous environments in which alternative phenotypes can exploit alternative resources. However, it’s not clear whether phenotypic plasticity is useful in environments that become more homogenous over an organism’s life cycle. I studied a population of grasshopper Melanoplus differentialis that experiences high resource diversity as nymphs but low resource diversity as adults to determine if individuals can undergo diet-induced morphological plasticity in head shape to increase biting ability and ingestion of hard diets. Insects on a soft diet were larger and had greater bite force than those on a hard diet. Head structures related to chewing …