Evolution 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, …

Multiple Insights Into Affective Sentience, Jon Mallatt, Todd E. Feinberg

Animal Sentience

We discuss some of the many valuable insights into affective sentience from Birch’s The Edge of Sentience, such as its eight criteria for determining which entities have sentience (e.g., emotions) and its insights into the difficulty of testing whether an Artificial Intelligence system has attained sentience. We add our own perspectives on why the eight criteria are valid, on the difficulty of using behavioral trade-offs to determine whether an animal has sentience, and why evolutionary theory says consciousness is not an epiphenomenon.

Phenotypic Variation Between Surface And Cave-Adapted Poeciliids And Its Effect On Metabolism, Karch Knipp, Michael Tobler, Soren Johnson

Undergraduate Research Symposium

Cave-adapted organisms often exhibit pronounced morphological changes relative to their surface counterparts, a phenomenon known as troglomorphy. In Poecilia mexicana (Atlantic molly), these differences include variation in coloration between surface and cave populations. Troglobitic organisms also typically exhibit reduced metabolic rates, likely as an adaptation to environments with low primary productivity. This makes P. mexicana an ideal system for investigating the evolution of metabolic traits. In this study, we leveraged variation in coloration among cave-dwelling mollies to examine potential associations with resting metabolic rate (RMR). Coloration was quantified using PCR values, and individuals were categorized as “yellow” or “non-yellow.” We …

Scorpio Basraensis Sp. N. From Southern Iraq (Scorpiones: Scorpionidae), Ersen A. Yağmur, Jafar A. Makki, Shurooq A. Najim

Euscorpius

A new scorpion species, Scorpio basraensis sp. n., is described and illustrated from Basra Province, southern Iraq. Scorpio basraensis sp. n. is compared with all known species of the genus Scorpio Linnaeus, 1758 occurring in countries surrounding Iraq. The new species can be distinguished by the circular genital operculum in males and the cordiform genital operculum in females (not posteriorly elongated), a densely hirsute body, appendages and metasoma, a distinctly elongated telson vesicle, discrete granules on the external surface of the chela manus that are not flattened, and pectinal tooth counts of 11–13 in males and 9–11 in females. …

Exploring Evolution As A Unifying Theme In The General Biology For Majors Course Sequence, While Iteratively Examining Attitudes And Decisions About Learning: An Application Of Lonergan’S Transcendental Method, Christine E. Gray

San Jose - Lonergan Chair in Catholic Philosophy

As I reflect upon my journey as an educator, I recognize it has been shaped, in large part, by my own foundational roots in the Catholic Liberal Arts tradition. As I prepare for another academic year, I find myself, once again, considering how my pedagogical practice can better meet my students “where they are” in my General Biology for Majors I and II courses. Since that “place” is shaped by a student’s prior experiences, both in and out of the classroom, I also recognize that “place” is unique for each student. This is precisely why each term pushes me to …

Exploring Foundations Of Animal Host-Microbe Interactions In A Freshwater Sponge, Jacob S. Pawley

Electronic Theses and Dissertations

The most ancient eukaryotic immune defense mechanisms evolved in unicellular species. Multicellular eukaryotes, however, expanded these mechanisms to meet challenges unique to multicellular life, including barrier formation, long-distance cell signaling, and coordinated responses that eliminate microbial threats while minimizing damage to the host. As such, animal immune signaling pathways are exceptionally intricate and diverse. Though, most of what is understood about animal host–microbe interactions stems from a small handful of model systems. Here, I evaluate host–microbe interactions and innate immunity in sponges using the highly tractable freshwater sponge, Ephydatia muelleri. I report the discovery of an external host-derived matrix …

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 …

Lizards In The Trees: Structural, Functional, And Behavioral Specializations To A High-Risk Environment, Victor D. Munteanu

All Dissertations

Animals must contend with unexpected changes in their habitat and environment to thrive. Arboreal habitats can consist of a wide variety of environmental features, and failure to adequately contend with these features can result in high risk of injury or death upon falling. Despite these strong selective pressures, many vertebrate lineages have successfully invaded arboreal habitats. Using lizard taxa as a model system, I investigated how morphology and behavior have evolved within this specific habitat transition. I pursued these investigations through complementary analyses including: 1) evaluating the effect of stance height and tail prehensility on perturbation recovery, 2) assessing behavior …

The Past, Present, And Future Of Climate Adaptation In A Widespread Lizard Species, Matthew R. Mcternan

All Dissertations

Climate, as a selective force, shapes patterns of biodiversity globally. However, how species adapt to climate remains a central question of biology. The need to understand climate adaptation is paramount, as global climate change threatens a large portion of global diversity. Climate can impose selection on life by either controlling rates of energy intake and expenditure through effects on body temperature and activity, or by exposing organisms to conditions beyond their physiological limits. Studies of climate adaptation have identified a wide-range of putatively adaptive phenotypic patterns, but genomic evidence is increasingly being used to investigate these patterns and better understand …

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.

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.

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.

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 …