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2024

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Full-Text Articles in Evolution

What Is It Like To Be A Diplomat? Reflections On Donald Griffin And Emotion, Oliver H. Turnbull Dec 2024

What Is It Like To Be A Diplomat? Reflections On Donald Griffin And Emotion, Oliver H. Turnbull

Animal Sentience

This commentary addresses three aspects of Donald Griffin’s work: (1) his thoughts beyond cognition, on emotion; (2) his views on the earliest origins of mind, including primitive forms of consciousness; and (3) his diplomatic use of memorable phrases to facilitate change.


Scorpiops Reini Sp. N. From Yunnan, China (Scorpiones: Scorpiopidae), Victoria Tang Dec 2024

Scorpiops Reini Sp. N. From Yunnan, China (Scorpiones: Scorpiopidae), Victoria Tang

Euscorpius

Scorpiops reini sp. n. is described from Yingjiang County (Dehong Prefecture, Yunnan Province) based on an adult pair. It can be readily discriminated from all of its congeneric geographic neighbors in Yunnan, namely S. jendeki Kovařík, 1994, S. shidian (Zhu et al., 2005), S. tongtongi Tang, 2022, and S. zhangshuyuani (Ythier, 2019). Within Yunnan, it resembles S. validus (Di et al., 2010) and S. yangi (Zhu et al., 2007) most, but can be identified by its large median ocelli (relative to the width of ocular subislet), pedipalp chelal finger morphology and pectinal tooth count. Beyond Yunnan, it shows the highest …


Hidden Markov Model For Identifying Local Variants In Human Genomes Using Simulated Data, Scott Mccallum Dec 2024

Hidden Markov Model For Identifying Local Variants In Human Genomes Using Simulated Data, Scott Mccallum

Electronic Theses and Dissertations

Identifying adaptive mutations in genetic data is challenging due to the low frequency of occurrence of such events, and because signatures of selection are intertwined with the footprints of various other evolutionary forces that shape our genomes. Even when a larger region appears to be under selection, genomic sites that are linked to adaptive mutations have similar statistical signals, and thus can obfuscate the identification of the actual adaptive mutation. The new method described here uses a Hidden Markov Model that allows for classification of neutral, linked, and sweep (adaptive mutation) genomic sites. This model is general and can be …


Star-Studded Stingers: Fluorescent Sensilla On The Scorpion Aculeus (Arachnida: Scorpiones), Graeme Lowe Dec 2024

Star-Studded Stingers: Fluorescent Sensilla On The Scorpion Aculeus (Arachnida: Scorpiones), Graeme Lowe

Euscorpius

The aculeus of the scorpion telson was studied by UV fluorescence microscopy. Numerous brightly fluorescent punctae were observed on the non-fluorescent distal aculeus, including the tip region. The punctae were identified as aculear sensilla coeloconica (ASC), and were connected to fluorescent canals running through the cuticle. ASC were present in both sexes, and in adults and immatures as early as the second juvenile instar, but were absent from the first instar. The distal aculeus was found to be encased in a thick, non-fluorescent dark exocuticle (DX), covering an underlying thin, fluorescent hyaline exocuticle (HX). Fluorescent ASC were recorded from 183 …


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxxiv. Four New Species Of Neobuthus From Somaliland (Buthidae), František Kovařík, Hassan Sh A. Elmi, František Šťáhlavský Dec 2024

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxxiv. Four New Species Of Neobuthus From Somaliland (Buthidae), František Kovařík, Hassan Sh A. Elmi, František Šťáhlavský

Euscorpius

New information about taxonomy and distribution of the genus Neobuthus Hirst, 1911 is presented, based on material recently collected in Somaliland. Four new species are described, N. dhobo sp. n., N. opatovae sp. n., N. osoli sp. n., and N. verae sp. n. (Somaliland). An updated distribution map of the genus Neobuthus is provided.


Testing Vivo-Morpholino Mediated Gene Knockdown Of Stat6, Spi1b, And Hnf4Α In Adult Threespine Stickleback, Stella Dipippo Dec 2024

Testing Vivo-Morpholino Mediated Gene Knockdown Of Stat6, Spi1b, And Hnf4Α In Adult Threespine Stickleback, Stella Dipippo

Honors Scholar Theses

The fibrotic immune response to the cestode parasite, Schistocephalus solidus, varies among threespine stickleback populations. Fibrosis suppresses parasite growth but has costly effects on the fish. Previous genomic studies in stickleback have suggested potential roles of Spi1b, STAT6, and HNF4α in modulating fibrosis severity, but there is presently no evidence for this in-vivo. We used antisense vivo-morpholino oligonucleotides (MOs) to attempt to knockdown the expression of each gene in the liver, spleen, and intestine of adult stickleback. Vivo-MOs have been proven effective in other species of teleost fish, as well as in mice and humans, but …


Analyzing Head Morphology Trends With Increasing Population Density In A Jamaican Lizard Species, Lillian Durand Dec 2024

Analyzing Head Morphology Trends With Increasing Population Density In A Jamaican Lizard Species, Lillian Durand

2024 Fall Honors Capstone Projects - Archive

Anolis lizards are model organisms for studying natural selection and evolutionary processes. One trait that is hypothesized to be advantageous for males is head size, as larger heads lead to stronger bite forces and increased likelihood in outcompeting other males for mates. To better understand how linked head size and intraspecific competition are, the head morphology of male A. lineatopus was analyzed among Jamaican populations with varying levels of population density. Population densities were determined using standardized plot surveys and mark resight models. Head dimensions and body condition for individual lizards were measured at each site. My study found that …


Evaluating The Roles Of Pollinators In Shaping The Floral Color Variation Of Phacelia Dubia, Katherine Riddle Dec 2024

Evaluating The Roles Of Pollinators In Shaping The Floral Color Variation Of Phacelia Dubia, Katherine Riddle

All Theses

Floral color variation within a species is a common occurrence and its maintenance has been a long-standing question in evolutionary biology. Differences in flower color between populations can be shaped by pollinator-mediated selection. Pollinators can exhibit innate and learned preferences for color that may influence floral color variation. These preferences may be molded by the visual environment in which pollinators forage. Most current understanding of how pollinators shape floral color variation involves dramatic differences in dominant pollinators between populations (e.g., hawkmoth vs. bee) and most behavioral work utilized model pollinators like honeybee and bumble bee. However, less is known about …


Species Distribution Modeling With Environmental Time Series Data And Deep Learning, Austin M. Smith Nov 2024

Species Distribution Modeling With Environmental Time Series Data And Deep Learning, Austin M. Smith

USF Tampa Graduate Theses and Dissertations

Species distribution models (SDM) are frequently used to gain ecological understanding and guide conservation decisions. These models are developed with a wide variety of procedures - from regression-based approaches to more modern machine learning algorithms - but a requirement almost all share is the use of predictor variables that strongly simplify the temporal variability of driving factors. These static features are chosen by the user, which can incorporate unnecessary bias into a study. Additionally, current data preparation techniques often remove variables from the process entirely, which inherently removes information that may still be of importance. Conversely, novel architectures of deep …


To Be Conscious Or Not To Be, Bjørn Grinde Nov 2024

To Be Conscious Or Not To Be, Bjørn Grinde

Animal Sentience

Carolyn Ristau has done a fine job summarizing the work and life of the zoologist Donald Griffin. Most scientists now accept the existence of animal sentience, but identifying which species possess consciousness remains controversial. Griffin defined consciousness as "the subjective state of feeling or thinking about objects and events.” Nonconscious processes are faster and more energy-efficient, however, and often drive behavior. Consciousness probably evolved for complex decision-making, shaped by evolutionary continuity, with feelings as a common currency for evaluating outcomes. Its survival advantage may be limited, and its presence across species varies depending on evolutionary trajectories.


Tityopsis Rolandoi Sp. N. (Scorpiones: Buthidae) From Cuba, František Kovařík, Mark Stockmann, František Šťáhlavský, Sheyla Yong Nov 2024

Tityopsis Rolandoi Sp. N. (Scorpiones: Buthidae) From Cuba, František Kovařík, Mark Stockmann, František Šťáhlavský, Sheyla Yong

Euscorpius

A new species Tityopsis rolandoi sp. n. is described from Cuba, fully illustrated with color photos showing its morphology and habitus. T. rolandoi sp. n. is the only species of the genus with a combination of two characters: movable finger shorter than carapace and chela length/width ratio 3.6 in male. This species also has a characteristic shape of a median smooth patch of sternite V, which is almost oval in male. In addition to morphology, we present the information about the karyotype of T. rolandoi sp. n. (2n=20) and T. sheylae (2n=22).


Communication In Noise Is The Window On Cognition, R. Haven Wiley Nov 2024

Communication In Noise Is The Window On Cognition, R. Haven Wiley

Animal Sentience

As Griffin surmised, communication is the window on cognition, but as shown here, only if it is noisy. This commentary is an invitation to consider the full implications of the evolution of noisy communication. A combination of Information Theory, Signal Detection Theory, and Natural Selection, in a unified theory of the evolution of communication, reveals that noise is inevitable. All organisms are thus decision makers. Perception, thought, freedom of decision, self-awareness, metabolism, and natural selection all share the consequences of signals in noise. A full understanding of each requires attention to the errors of receivers. Griffin’s hunch is correct with …


Understanding The Welfare Of Aquarium Fish, Paul Rose Nov 2024

Understanding The Welfare Of Aquarium Fish, Paul Rose

Animal Sentience

Bony fishes (Osteichthyes) are prevalent in public and domestic aquaria, yet evidence-based welfare practices exist for only a limited number of species. Oldfield & Bonano’s (O&B’s) target article highlights critical questions about the wellbeing and sociality of Osteichthyes. Advancing research on their biology, physiology, psychology, and behavior is essential to develop and validate welfare measures, ensuring guidelines for welfare-focused housing and husbandry.


Structural Molecular And Developmental Evidence For Cell-Type Diversity In Cnidarian Mechanosensory Neurons, Julia Baranyk, Kristen Malir, Miguel A.P. Silva, Sakura Rieck, Gracie Scheve, Nagayasu Nakanishi Nov 2024

Structural Molecular And Developmental Evidence For Cell-Type Diversity In Cnidarian Mechanosensory Neurons, Julia Baranyk, Kristen Malir, Miguel A.P. Silva, Sakura Rieck, Gracie Scheve, Nagayasu Nakanishi

Biological Sciences Faculty Publications and Presentations

Deploying a conserved mechanosensory neuron known as the concentric hair cell, cnidarians have evolved diverse mechanoreceptors from hydroid filiform tentacles to jellyfish statocysts. However, it is unknown whether cnidarian mechanoreceptor evolution has relied solely on repurposing a single ancestral mechanosensory neuron type. Here we report evidence for cell-type diversity of mechanosensory neurons in sea-anemone cnidarian Nematostella vectensis. Uncovered in the ectoderm of feeding tentacles are conventional type I hair cells and previously unrecognized type II hair cells differing in the structure of apical sensory apparatus and synapses. Moreover, we identify TRP channel-encoding gene polycystin-1 as a type-II-hair-cell-specific essential mediator of …


Changes In Morphology, Phenology, Demography Of Several Avian Species Over 18 Years At A Restored Grassland, Ashley Mcmahon, Katie Stumpf, Charlie Muise Oct 2024

Changes In Morphology, Phenology, Demography Of Several Avian Species Over 18 Years At A Restored Grassland, Ashley Mcmahon, Katie Stumpf, Charlie Muise

Biology Theses

In response to a changing climate and habitat loss, avian species are displaying changes in body size, migration phenology, and demography. Species have often adhered to Allen’s and Bergmann’s rules, displaying increased wing length and decreased body mass, respectively, over time in response to higher temperatures. Additionally, climate change has resulted in earlier spring migration and depending on species, either earlier or later fall migration. Finally, species affected by habitat loss often display male-skewed sex ratios and juvenile skewed age ratios. Our goal was to determine how 1) body size, 2) migration phenology, and 3) demography have changed for grassland …


Scorpiops Tangae Sp. N. (Scorpiones: Scorpiopidae) From Laos, František Kovařík, František Šťáhlavský, Mark Stockmann Oct 2024

Scorpiops Tangae Sp. N. (Scorpiones: Scorpiopidae) From Laos, František Kovařík, František Šťáhlavský, Mark Stockmann

Euscorpius

A new species Scorpiops tangae sp. n. is described from Laos, fully illustrated with color photos showing its morphology and habitus. Scorpiops tangae sp. n. is the only species of the genus with a combination of five characters: chelal trichobothrium Eb3 located in distal half of manus between trichobothria Dt and Est; patella of pedipalp with 11 ventral and 17 external trichobothria; fingers of pedipalps undulate in male; pedipalp movable finger with ca. 45 IAD; and chela length to width ratio 3.7 in male. In addition to morphology and hemispermatophore, we also present the …


Clustered Setation On The Pedipalps Of Buthid Scorpions (Scorpiones: Buthidae), Graeme Lowe, Victoria Tang Oct 2024

Clustered Setation On The Pedipalps Of Buthid Scorpions (Scorpiones: Buthidae), Graeme Lowe, Victoria Tang

Euscorpius

Chaetotaxy of the external pedipalp femur and distal ventral pedipalp movable finger was studied in 120 species, 69 genera and 17 families of scorpions. Setation was generally denser in the ‘Buthus’ group, a major arid-adapted buthid lineage distributed across Palearctic deserts. On the external femur, macrosetae formed a prominent cluster, the ‘distal external macrosetal cluster’ (DEMC); on the distal ventral movable finger they formed a dense patch, the ‘distal ventral macrosetal cluster’ (DVMC). In other buthids and non-buthids, the DEMC and DVMC were mostly absent, except in a few arid-adapted genera. Relative setation densities of DEMC and DVMC in different …


Uroplectes Ebogo Sp. N. (Scorpiones: Buthidae) From Cameroon, František Kovařík, František Šťáhlavský, Valeriy Govorov Oct 2024

Uroplectes Ebogo Sp. N. (Scorpiones: Buthidae) From Cameroon, František Kovařík, František Šťáhlavský, Valeriy Govorov

Euscorpius

A new species Uroplectes ebogo sp. n. is described from Cameroon, fully illustrated with color photos showing its morphology and habitus. Uroplectes ebogo sp. n. is the only species of the genus with a combination two characters: metasoma without carinae and metasoma V and telson without punctuation. In addition to morphology and hemispermatophore, we also present the information about the karyotype of Uroplectes ebogo sp. n. (2n=24).


Albinism In Olivierus Martensii (Karsch, 1879) (Scorpiones: Buthidae), Victoria Tang, Zhenbang Liu Oct 2024

Albinism In Olivierus Martensii (Karsch, 1879) (Scorpiones: Buthidae), Victoria Tang, Zhenbang Liu

Euscorpius

This is a formal case report for the albinism in Olivierus martensii (Karsch, 1879). Albino phenotype is compared with its normal counterpart in terms of their morphology and behavior by cursory experiments. The examined 7 albino individuals (5 of which were adults) were smaller and more slender than their normal counterparts. However, these quantitative differences were not statistically significant and should be treated with caution due to the low sample size. Their abilities to detect both white light and UV light or UV-excited fluorescence were not significantly undermined, although their tendency to ensure a clear vision through self-cleaning behavior appeared …


Ontogenetic Biomechanics Of Tufted (Sapajus) And Untufted (Cebus) Capuchin Mandibles, Taylor A. Polvadore, Caitlin B. Yoakum, Parker M. Taylor, Megan A. Holmes, Myra F. Laird, Janine Chalk-Wilayto, Claudia Misue Kanno, Jose Americano De Oliveira, Claire E. Terhune Oct 2024

Ontogenetic Biomechanics Of Tufted (Sapajus) And Untufted (Cebus) Capuchin Mandibles, Taylor A. Polvadore, Caitlin B. Yoakum, Parker M. Taylor, Megan A. Holmes, Myra F. Laird, Janine Chalk-Wilayto, Claudia Misue Kanno, Jose Americano De Oliveira, Claire E. Terhune

Anthropology Faculty Publications and Presentations

Objectives

Cortical bone geometry is commonly used to investigate biomechanical properties of primate mandibles. However, the ontogeny of these properties is less understood. Here we investigate changes in cortical bone cross-sectional properties throughout capuchin ontogeny and compare captive versus wild, semi-provisioned groups. Tufted capuchins (Sapajus spp.) are known to consume relatively hard/tough foods, while untufted capuchins (Cebus spp.) exploit less mechanically challenging foods. Previous research indicates dietary differences are present early in development and adult Sapajus mandibles can resist higher bending/shear/torsional loads.

Materials and methods

This study utilized microCT scans of 22 Cebus and 45 Sapajus from early …


Précis Of: "Birds, Bats And Minds: Tales Of A Revolutionary Scientist, Donald R. Griffin", Carolyn A. Ristau Oct 2024

Précis Of: "Birds, Bats And Minds: Tales Of A Revolutionary Scientist, Donald R. Griffin", Carolyn A. Ristau

Animal Sentience

Donald Griffin co-discovered bat sonar and founded the field of echolocation. He studied bird migration and founded Cognitive Ethology, the study of animal awareness and mental experiences. In all these endeavors, he faced hostile opposition. The biography (Ristau 2024) examines Griffin's life and the scientific explorations by him and others in these fields. This Précis emphasizes his arguments and supporting evidence for animal consciousness as well as his later research. Griffin considered the inhibiting assumptions made by scientists, including Cartesian views, the misunderstanding of innate behaviors, prejudice against lower animals, concern with violations of parsimony, and the assertions of the …


The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French Sep 2024

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 …


Diverse Origins Of Near-Identical Antifreeze Proteins In Unrelated Fish Lineages Provide Insights Into Evolutionary Mechanisms Of New Gene Birth And Protein Sequence Convergence, Nathan Rives, Vinita Lamba, C.H. Christina Cheng, Xuan Zhuang Sep 2024

Diverse Origins Of Near-Identical Antifreeze Proteins In Unrelated Fish Lineages Provide Insights Into Evolutionary Mechanisms Of New Gene Birth And Protein Sequence Convergence, Nathan Rives, Vinita Lamba, C.H. Christina Cheng, Xuan Zhuang

Biological Sciences Faculty Publications and Presentations

Determining the origins of novel genes and the mechanisms driving the emergence of new functions is challenging yet crucial for understanding evolutionary innovations. Recently evolved fish antifreeze proteins (AFPs) offer a unique opportunity to explore these processes, particularly the near-identical type I AFP (AFPI) found in four phylogenetically divergent fish taxa. This study tested the hypothesis of protein sequence convergence beyond functional convergence in three unrelated AFPI-bearing fish lineages. Through comprehensive comparative analyses of newly sequenced genomes of winter flounder and grubby sculpin, along with available high-quality genomes of cunner and 14 other related species, the study revealed that near-identical …


Methodologies For Dry Fixation And Taxidermy Of Education-Oriented Scorpion Specimens, Victoria Tang Aug 2024

Methodologies For Dry Fixation And Taxidermy Of Education-Oriented Scorpion Specimens, Victoria Tang

Euscorpius

Scorpions hold a renowned status as iconic creatures across numerous cultures in the world. Traditionally preserved as desiccated specimens for educational purposes, they have been exhibited in museums and pedagogic collections, serving as concrete epistemological conduits for public education on biodiversity. However, these specimens frequently lack meticulous organization, potentially misrepresenting the animals’ ethological characteristics. This brief article aims to offer paradigmatic guidance for taxidermy of scorpions, ensuring a more accurate depiction of their in vivo habitus, achievable through the use of readily obtainable tools and undemanding techniques.


Three New Species Of Genus Scorpiops Peters, 1861 From Tibet, China (Scorpiones: Scorpiopidae), With Implications For The Diagnostic Values Of Qualitative Characters, Victoria Tang, Kaichen Ouyang, Zhenbang Liu, František Šťáhlavský Aug 2024

Three New Species Of Genus Scorpiops Peters, 1861 From Tibet, China (Scorpiones: Scorpiopidae), With Implications For The Diagnostic Values Of Qualitative Characters, Victoria Tang, Kaichen Ouyang, Zhenbang Liu, František Šťáhlavský

Euscorpius

Three new species of genus Scorpiops Peters, 1861 are described from Tibet Autonomous Region, China. S. deshpandei sp. n. is described based on an adult male and an immature pair collected from Mêdog County, Nyingchi, with additional molecular evidence substantiating its validity against S. longimanus Pocock, 1893. S. kovariki sp. n. is featured by a single adult female from Zayü. This species is only weakly supported by its genetic distance from S. jendeki Kovařík, 1994, but empirical understanding of the morphological variation in Scorpiops species motivated us to consider them as distinct. S. matthewi sp. n. is based on …


Euscorpius Gulhanimae Sp. N. From The Konya Province, Turkey (Scorpiones: Euscorpiidae), Ersen A. Yağmur Aug 2024

Euscorpius Gulhanimae Sp. N. From The Konya Province, Turkey (Scorpiones: Euscorpiidae), Ersen A. Yağmur

Euscorpius

A new species Euscorpius gulhanimae sp. n. is described from southern Turkey (Beyşehir District of Konya Province). It differs by trichobothrial numbers in Pv and et series; these numbers are the highest in all species of Euscorpius in Turkey. E. gulhanimae sp. n. has light greyish yellow mesosoma, dark reddish-brown chela and dark brown metasomal segments III-V; the new species is distinguished by this two-colored feature from all Euscorpius species. With this description, the known number of species in the family Euscorpiidae in Turkey is increased to 21.


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxxiii. Three New Species Of Gint From Ethiopia And Somaliland (Buthidae), František Kovařík, Hassan Sh A. Elmi, František Šťáhlavský Aug 2024

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxxiii. Three New Species Of Gint From Ethiopia And Somaliland (Buthidae), František Kovařík, Hassan Sh A. Elmi, František Šťáhlavský

Euscorpius

Three new species, Gint sahil sp. n. from Somaliland and Gint abshiri sp. n. and G. derbiae sp. n. from Ethiopia are described and compared with other species of the genus. Additional information is provided on the taxonomy and distribution of the genus Gint, fully complemented with color photos of specimens of the new species, as well as of their habitats. Furthermore, alongside the analyses of external morphology and hemispermatophores, we have provided description of the karyotype of G. abshiri sp. n. This species exhibits karyotype with 2n=27. Included is distribution map and a key for the genus Gint …


Revision Of The Genus Scorpio In Jordan, With A Description Of A New Genus And Three New Species (Scorpiones: Scorpionidae), Bassam Abu Afifeh, Ersen A. Yağmur, Mohammad Al–Saraireh, Zuhair Amr Aug 2024

Revision Of The Genus Scorpio In Jordan, With A Description Of A New Genus And Three New Species (Scorpiones: Scorpionidae), Bassam Abu Afifeh, Ersen A. Yağmur, Mohammad Al–Saraireh, Zuhair Amr

Euscorpius

Several new Scorpio populations are studied from various habitats in Jordan, including specimens previously identified as Scorpio kruglovi Birula, 1910 and S. fuscus (Ehrenberg, 1829). A new scorpionid genus, Jordanius gen. n. is described, mainly differentiated from the genus Scorpio Linné, 1758 by the elongation and heavy patterns of granulation of chela manus, and granulated chela fingers. Scorpio granulomanus Al-Saraireh et al., 2023 is transferred to the new genus, and Jordanius maysaraensis gen. et sp. n. is described. Also, Scorpio jordanensis sp. n. and S. wahbehi sp. n. are described. Detailed …


A Comparative Analysis Of Extant Oceanic Shark Species Using Trait-Based Ecology, Elizabeth A. Johnson Aug 2024

A Comparative Analysis Of Extant Oceanic Shark Species Using Trait-Based Ecology, Elizabeth A. Johnson

All HCAS Student Capstones, Theses, and Dissertations

Over the past few decades, scientists have been working together to mitigate human impacts on global shark populations, but deciding which species need the most immediate attention can be difficult. This study uses a newly emerging approach to ecology, trait-based ecology, to identify trends in trait expression with depth and determine which species have the most unique sets of traits. While trait-based ecology has already been applied to numerous fields, a trait-based approach to shark research is still in its infancy. A total of 15 traits across 337 oceanic shark species were examined to identify trends in trait expression and …


The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson Aug 2024

The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson

Biology ETDs

Elevational gradients cause profound eco-climatic variation across short distances. Partial pressure of oxygen (PO2) is a severe challenge that organisms face at high elevations; due partly to specialization on PO2, most Neotropical bird species have narrow elevational ranges. However, a small fraction are elevational generalists that span sea level to high elevations, and a subset undertake extreme migratory journeys from low to high elevations biannually. My dissertation combines diverse approaches across levels of biological organization to understand how elevation impacts the ecology, evolution, physiology, and migration of montane birds. I examined ‘extreme’ elevational …