Ecology and Evolutionary Biology Commons^™

Sexual Di(Et)Morphism: Using Experimental Evolution To Test Whether Resource Partitioning Promotes Divergence Of The Sexes In Drosophila Melanogaster, Owen A. Jamieson

Theses and Dissertations (Comprehensive)

Sexual dimorphism has been a long-studied phenomenon in the field of evolutionary biology. Usually, these differences in morphology, physiology and/or behaviour between the sexes are studied through the parsimonious lens of sexual selection. However, there are natural history cases where this lens does not seem applicable. Some species show sex specific morphological traits whose presence may not be due to a direct benefit to reproduction, but a difference in how each sex interacts with the environment and differing selective pressures from the environment on either sex. Darwin even brought up examples of this kind of dimorphism and pondered their existence, …

A New Species Of Liocheles Sundevall, 1833 (Scorpiones: Hormuridae) From The Western Himalayas, Virender К. Bhardwaj, Sunil Katal, H. T. Lalremsanga, Zeeshan A. Mirza

Euscorpius

Sampling in the Western Himalayas of India led to the discovery of a population of the genus Liocheles Sundevall, 1833, that differes from all Indian congeners. Molecular and morphological data confirmed the distinctiveness of the population, which is here described as a new species. The new species is morphologically similar to L. longimanus (Werner, 1939), from which it differs in the arrangement of trichobothria on external patella and structure of the hemispermatophore. A preliminary molecular phylogeny of the family Hormuridae based on the mitochondrial cytochrome oxidase I gene is presented.

New Locality Records And Future Habitat Suitability Of Sassanidotus Gracilis (Birula, 1900) (Scorpiones: Buthidae) In The Iran–Afghanistan–Pakistan Arid Belt, Ersen A. Yağmur, Kerim Çiçek, Homa Barati, Mohammad Moradi

Euscorpius

This study reports new locality records from Iran and a climate-based habitat suitability assessment for Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt. We document new specimens from Sistan and Baluchestan Province, Iran, with an updated distribution map and illustrations, and we model the species' potential distribution across south-eastern Iran and adjacent parts of Afghanistan and Pakistan.

Habitat suitability was associated mainly with precipitation seasonality, precipitation of the wettest month, precipitation of the driest month, and slope. In an arid setting these rainfall variables are unlikely to indicate a need for moist habitat; they more plausibly track …

First Insular Record And Dna Barcoding Of Euscorpius Vailatii Tropea & Fet, 2015 From Trizonia Island (Fokida, Greece), Konstantinos Kalaentzis, Francesco Frigioni, Alexios Panagiotopoulos, Elias Tzoras, Styliani Minoudi, Alexandros Triantafyllidis

Euscorpius

Euscorpius vailatii Tropea & Fet, 2015 (Scorpiones: Euscorpiidae), originally described from Aitoloakarnania and Fokida (Greece), is herein reported from Trizonia Island in the Gulf of Corinth, representing the first insular record for the species. The examined specimens are consistent with the diagnostic morphology of E. vailatii. The first molecular data for the species are provided, based on both mainland and insular populations. Comparative analyses further highlight the distinctiveness of E. vailatii from geographically close congeners, while phylogenetic results indicate a sister-taxon relationship with E. erymanthius, supporting a Quaternary biogeographic history shaped by the evolution of the Gulf of …

Formalization Of Nomenclatural Acts Proposed In Tang (2026) (Scorpiones: Buthidae, Chaerilidae, Scorpiopidae), Victoria Tang

Euscorpius

Several nomenclatural, taxonomic, and faunistic decisions put forth in Tang (2026) are formalized herein: (1) four nomina dubia, Chaerilus tessellatus Qi et al., 2005, Scorpiops langxian Qi et al., 2005, S. pococki Qi et al., 2005, and Isometrus (Reddyanus) wenjieae Huang et al., 2025; (2) two junior subjective synonyms, Scorpiops langxian = S. pococki = S. tibetanus Hirst, 1911 syn. n.; (3) one new “aspidonym”, Scorpiops obluda Tang, 2026 sp. indet. nomen nudum; and (4) removal of Scorpiops hardwickii (Gervais, 1843) and S. petersii Pocock, 1893 from the Chinese scorpiofauna. Reddyanus tibetanus (Lourenço & Zhu, 2008) is maintained …

A Geometric Morphometric Analysis Of Acetabular Shape Variation Across Bat Families, Jordan L. Huff

Electronic Theses and Dissertations

Bats are the only mammals capable of powered flight, and research is concentrated on this adaptation. Their non-flight locomotion has received comparatively little attention. Previous studies show that non-flight locomotor behaviors vary across families. Members of Pteropodidae are efficient climbers but cannot effectively walk, whereas Phyllostomidae and Vespertilionidae are better at terrestrial locomotion but show reduced arboreal capabilities. The non-flight locomotion of Hipposideridae and Rhinolophidae is less understood, although rhinolophids exhibit limited terrestrial locomotion. This study examined whether differences in locomotor behavior are associated with variation in acetabular morphology. A geometric morphometric analysis of acetabular shape was conducted across multiple …

What Does Sentience Mean At The Neural Level?, Björn Brembs

Animal Sentience

Jonathan Birch's (2025) LSE criteria for sentience include motivational trade-offs, exemplified by C. elegansweighing hunger against desiccation risk. Yet once the neural circuit is known, this "trade-off" reduces to a single inhibitory synapse—an ‘elemental’ account discrediting the ‘molar’ one. My commentary illustrates the same discrepancy in Drosophila: dopaminergic ramping during courtship as it progressively suppresses threat-detecting neurons; so persistence past danger reflects recalibrated valuation rather than a weighed decision. As neurobiology increasingly discovers such discrepancies, all criteria resting on behavioral classifications risk being defined away without altering the behavior's validity.

Scorpiops Walteri Sp. N. (Scorpiones: Scorpiopidae) From Myanmar, František Kovařík

Euscorpius

A new species Scorpiops walteri sp. n. (Scorpiopidae) is described from Myanmar, fully illustrated with color photos showing its morphology and habitus. Scorpiops walteri sp. n. is the only species of the genus with a combination of the following five characters: chelal trichobothrium Eb₃ located in middle of manus between trichobothria Dt and Est; patella of pedipalp with 11–12 ventral and 19 external trichobothria; fingers of pedipalps strongly undulate in male; pedipalp movable finger with ca. 47 IAD; and chela length to width ratio 2.8 in male.

Look Out For Our Kind, Christof Koch

Animal Sentience

Strongly supportive overall of Birch’s broad tent Sentience Project, I offer an alternative dyadic, single-class, two-stage process based on estimating the probability for sentience, and the associated confidence, for any individual or taxonomic group. I criticize Birch’s narrow computational framework when addressing the question of algorithmic sentience; there are alternative approaches.

Ai Is Not The Kind Of Thing That Can Ever Be Sentient, Lori Marino

Animal Sentience

Sentience evolved to allow organisms to move through their environment avoiding harms and achieving benefits. Sentience did not evolve from computation. It evolved from valenced feelings. AI (even robots) are not embodied and are not the kind of thing that needs to be sentient. There is no way to get from computations to feelings. They are qualitatively different things. We should avoid being lulled into thinking that an inanimate object designed to engage our propensity for anthropomorphism, like AI, is actually a mind.

Euscorpius Emae Sp. N. (Scorpiones: Euscorpiidae), A New Scorpion Species From Montenegro, František Kovařík

Euscorpius

A new species Euscorpius emae sp. n. (Scorpiones: Euscorpiidae) from Montenegro is described, fully complemented with color photographs. E. emae sp. n. is morphologically unique by yellow to orange color, very narrow metasoma and enlarged chela. Pedipalp patella external trichobothria numbers are 4eb, 4eb_a, 2esb, 4em, 4est, 5et, and ventral aspect of patella with 9 trichobothria.

Tails From The Isle Of Devils: Two New Records Of Non-Native Invasive Scorpions (Arachnida: Scorpiones) Successfully Intercepted In Bermuda, Including The First Record Of Caraboctonidae, Danniella Sherwood, Mark Outerbridge, Struan R. Smith, Jenny Gosling, Myles Darrell

Euscorpius

Hadruroides sp. (Scorpiones: Caraboctonidae) is newly recorded as a successfully intercepted non-native invasive species in Bermuda, based on examination of a desiccated and damaged immature female specimen. A second record of an intercepted Centruroides gracilis (Latreille, 1804) (Scorpiones: Buthidae) is reported based on examination of an adult male.

Scorpions Of Angola (Arachnida, Scorpiones). Part I. Family Buthidae, With Descriptions Of Two New Species., František Kovařík

Euscorpius

All scorpion species of the family Buthidae known from Angola are listed, with color photographs and maps of their distribution. Diagnosis of Babycurus ansorgei Hirst, 1911 is revised; its male is described for the first time. Babycurus crassicaudatus Roewer, 1952, is revalidated (it was erroneously synonymized with B. ansorgei, since the females of both species are morphologically almost identical). Uroplectes angolensis sp. n. and U. xavieri sp. n. are described from Angola. Validity of Uroplectes ngangelarum Monard, 1930 is confirmed as different from U. planimanus (Karsch, 1879); its lectotype is designated. Lectotype is also designated for Uroplectes planimanus …

On The Edge Of Science?, Mark Briffa, Lynne U. Sneddon

Animal Sentience

In The Edge of Sentience, Jonathan Birch (2024) provides a thought-provoking synthesis of current perspectives on animal (and artificial) sentience. He addresses the question from conceptual, ethical, regulatory and empirical viewpoints. Here we focus on some of the scientific issues raised, including defining and operationalising the concept of sentience and the implications for policy and regulation. Despite unresolved conceptual challenges, the book makes a compelling case for the continued scientific investigation of animal sentience.

From The Edge To The Grounds Of “Sentientism”, David Degrazia

Animal Sentience

Birch’s book is a remarkable exploration of the nature of sentience, its moral salience, evidence for its presence, and how to arrive at humane policies regarding our treatment of human beings, animals, brain organoids, and AI systems of uncertain sentience. Although Birch endorses the view that sentience is of fundamental moral importance, he endeavors to remain neutral among reasonable moral views and work out how to navigate through uncertainty—both ethical and epistemological—to arrive at defensible policies. While making common cause with Birch’s project, my own recent book advances a developed case in favor of the “sentientism” Birch endorses.

Natural Behavior Vs. Subjective Experience In Fish Welfare Assessments, Ronald G. Oldfield

Animal Sentience

Several commentaries on the Oldfield & Bonano (2024) target article proposed that natural behavior should play a larger role in assessing the welfare of fishes in zoos and aquariums. However, the natural-behavior concept of animal welfare has been widely criticized because natural behaviors do not necessarily improve welfare, and unnatural behaviors do not necessarily reduce it. I review the three major concepts of animal welfare — physical health, natural behavior, and affect/feelings — and argue that behavior patterns, whether natural or otherwise, should be evaluated according to their effects on health and subjective experience. Using the affect/feelings concept and the …

Effect Of Temperature On The Defensive And Predatory Behavior Of The Scorpion Hadrurus Obscurus (Scorpiones: Hadruridae), Zia Nisani, Megan Bennett, Audrey Enriquez, Mel Iniquez, Emilia Martinez Rios, Brooklyn Stone

Euscorpius

Scorpions employ their stinging mechanism both for defense and predation, and being ectothermic, temperature influences their physiology and behavior. As such, we hypothesized that temperature both affects defensive stinging and prey-capture behavior in scorpions. We tested the effects of body temperature on these behaviors in the desert hairy scorpion, Hadrurus obscurus Williams, 1970. In the first experiment, scorpions were placed in temperature-controlled chambers with either high (26-28°C) or low (21- 22°C) temperatures and probed to elicit a defensive sting. We recorded the reaction time and the number of probes needed to elicit a sting. In the second experiment, we observed …

Pickleweed In The Disappearing Marsh: Population Genetics & Metal Accumulation In Salicornia Depressa, Alice Kaisla

Graduate Doctoral Dissertations

Salicornia is a genus of succulent halophytes found in salt marshes around the world. Salicornia species have a remarkably high tolerance for heavy metal pollution and have been shown to accumulate high concentrations of heavy metals in their tissue under experimental conditions. As a result, they are both a useful system for studying evolution in polluted coastlines and a potential candidate for use in phytoremediation. My research focuses on Salicornia depressa, known as pickleweed, a species commonly found in marshes along the heavily urbanized and industrialized New England coast. I investigate genetic diversity and population structure in S. depressa populations …

Patents And Technology Evolution: Altering Innovations And Innovators Via Patent Influences, Richard Gruner

Georgia Journal of Law & Technology

Technologies improve primarily through evolutionary change not rational optimization. New technologies emerge as attempts to solve practical problems, the technologies are tested in marketplaces to determine if they are superior in cost and function to alternatives, and those that fare well in the testing gain widespread adoption.  Widely adopted technologies, and their problems, form the basis for the next round of technology improvements and evolution.  Through these steps, evolutionary processes lacking rational direction can generate changing technologies matched to the desires and problems of present society.

As they operate to advance diverse technologies, evolutionary processes governing technology change are subject …

Compsobuthus Hadeki Sp. N. From Iraq (Scorpiones: Buthidae), František Kovařík, František Šťáhlavský

Euscorpius

A new species, Compsobuthus hadeki sp. n. from Iraq is described and fully complemented with color photographs and compared with morphologically the most similar species, C. matthiesseni (Birula, 1905). The two species can be unequivocally separated by the following morphological features: in C. hadeki sp. n., movable finger of pedipalp bears 9 rows of granules; telson with aculeus shorter than vesicle, and metasoma III with 10 carinae. Cytogenetic analysis was performed, revealing a diploid chromosome count of 22 in C. hadeki sp. n.

Investigating Cryptic Diversity In The Hawaiian Endemic Plant, Psychotria Mariniana (Rubiaceae), Uyen Thi Hoang Nguyen

Master's Theses

Islands, with their isolation and steep environmental gradients, serve as natural laboratories for studying speciation. Molecular phylogenetic and population genetic methods utilizing Next-Generation Sequencing (NGS) have revolutionized our ability to document patterns of genetic divergence and diversity. Cryptic diversity, genetically distinct populations that were previously unrecognized as unique, and cryptic speciation, where divergent genetic populations may be deserving of status as unique species, have been observed in many taxa. The Hawaiian Islands provide an ideal setting for studying divergence and speciation due to their extreme isolation, known ages, and volcanic origin. Previous work has investigated the evolutionary relationships of the …

Structure And Diversity Of Play Behavior In Juvenile Belding's Ground Squirrels, Paul O'Driscoll Ii

Master's Theses

Play behavior is ubiquitous among juvenile mammals and can promote motor, social, and cognitive development, providing multiple adaptive benefits to young animals in some cases. The structure of play can be linked to the benefits it confers on individuals. I evaluated the structure of play in juvenile Belding’s ground squirrels (Urocitellus beldingi), a species for which multiple adaptive benefits of play have been identified. I compared juvenile play in U. beldingi to adult sexual and aggressive behavior to determine and classify similarities between juvenile play and adult behavior. I evaluated diversity in the behaviors expressed during play interactions and diversity …

A Reassessment Of “Tityus” Tenuimanus Banks, 1910, As A Misidentified Leiurus Sp. (Scorpiones: Buthidae), Mohamed Mousaid, Ersen A. Yağmur, Zoe Flores, Alana Rivera, Aziza Lansari, Abdellah Bouazza

Euscorpius

This study re-examines the holotype of “Tityus” tenuimanus Banks, 1910, previously synonymized with Buthus atlantis Pocock, 1889 by Lourenço & Francke (1984). Our results indicate that the specimen is a misidentified representative of Leiurus Ehrenberg, 1828, as it exhibits the diagnostic characters of this genus: the central lateral and posterior median carinae of the carapace fused into a lyre-shaped configuration, and tergites I–II bearing five granular carinae (a character absent in the genus Buthus Leach, 1815). Moreover, the holotype lacks one of the most distinctive characters of the genus Tityus Koch, 1836, namely the presence of a subaculear tubercle. The …

Scorpions In Brazilian Caves And Other Subterranean Habitats, Jonas E. Gallão, Bruno D, Lenhare, Misael Oliveira-Neto, Maria E. Bichuette

Euscorpius

Arachnids have successfully colonized subterranean environments. Compared to spiders, harvestmen, and pseudoscorpions, scorpions have a moderate number of subterranean species, including troglophiles and troglobites. Among the four families and 184 species and three subspecies of scorpions found in Brazil, three families and at least 33 species and one subspecies have been documented in subterranean habitats. This study presents a faunistic list of scorpion occurrences in caves and other types of subterranean habitats in Brazil, along with distribution maps and an attempt to classify species based on their use of and dependence on subterranean environments.

The Genus Nebo Simon, 1878 (Scorpiones: Diplocentridae) In Oman, Graeme Lowe

Euscorpius

No abstract provided.

Quantifying Genetic Diversity In Nematode Feeding Rate, Jacob King

Honors Theses

Understanding how populations persist under changing environmental conditions is a central question in ecology and evolutionary biology. Variation in traits related to resource acquisition may play a key role in determining population survival when resources are limited or fluctuate over time. In this study, I investigated how variation in feeding-related traits influences population persistence using a combination of computational modeling and laboratory experiments. I developed a stochastic, individual-based consumer–resource model to simulate population dynamics across varying levels of trait variance and resource regimes. Across 60,000 simulated populations, increased trait variation consistently reduced extinction risk and extended persistence time, although the …

I Lost My Number, Can I Have Yours? Body Image Satisfaction With Sexually Dimorphic Traits Is Associated With Men's Dating Anxiety And Confidence, David A. Frederick, Tania A. Reynolds, Nikoline L. Smart, Justin R. Garcia, David A. Puts

Psychology Faculty Articles and Research

Evolutionary scientists posit that sexual selection processes caused males to develop sexually dimorphic traits to aid them during intrasexual competition and increase their likelihood of being chosen as mates. Evolutionary social sciences have extensively examined women's preferences for traits such as muscle mass and voice pitch, reasoning that these traits serve as cues of men's ability to provide direct benefits (e.g., resources) and indirect (genetic) benefits passed on to offspring. At the same time, body image researchers have extensively focused on the social causes and consequences of men's dissatisfaction with their muscularity and body fat. We connected these two research …

Polydactyl Precursors: Insights Into Early Tetrapod Locomotion From Polydactyl American Alligators, Trevor P. Brewington

All Theses

Several of the earliest tetrapod lineages exhibited polydactyl limbs, with seven or eight digits per limb rather than the typical five or fewer seen in extant lineages. How these digit configurations might have been used during terrestrial locomotion is unclear, given the lack of living models in which their performance can be studied and limited evidence from fossil trackways. However, polydactyly occasionally appears in natural populations of American alligators (Alligator mississippiensis), animals with body plans that broadly resemble those of early tetrapods. To test how polydactyl limbs similar to those of early tetrapods might have functioned on land, …

Shape Variation In The Mandible Of The Borophagine Canids And Implications For Predatory Behavior, Benjamin Neavear

Theses, Dissertations and Culminating Projects

The borophagines are an extinct lineage of canids that inhabited North America for more than 20 million years. This group included genera such as Aelurodon, Borophagus, and Epicyon. Borophagines are commonly referred to as “bone-crushing dogs” because their skull morphology converged with that of extant hyenas, predators capable of consuming bone. The purpose of this study was to determine whether convergence was present in the mandible, an anatomical structure strongly correlated with feeding behavior, particularly in the genera Aelurodon and Borophagus. It was hypothesized that most borophagine taxa possessed mandibular shapes similar to those of hyenas. Numerous mandibular characters were …

Morphological Variation Of Lingual Glands In Wild American Alligator (Alligator Mississippiensis) Populations, Benjamin Angalet

Master's Theses

American alligators (Alligator mississippiensis) inhabit diverse aquatic ecosystems including freshwater wetlands, swamps, and estuarine rivers. As apex predators, their physiological resilience has implications for ecosystem stability and long-term conservation. With projected sea-level rise and increasing saltwater intrusion into coastal freshwater habitats, understanding the osmoregulatory capacity of alligators is increasingly important. Unlike marine-tolerant crocodilians such as the saltwater crocodile (Crocodylus porosus), which possess specialized salt-secreting lingual glands in addition to renal and cloacal mechanisms, the morphology and physiological significance of lingual glands in wild American alligators remain poorly understood. This study examined lingual gland morphology and plasma …