Antisymmetry is a striking, yet puzzling form of biological asymmetry. The livebearing fish Xenophallus umbratilis exhibits antisymmetry in the male intromittent organ and provides a system that is well-suited for studying the nature of variation in antisymmetrical traits. Using geometric morphometrics, I test the hypothesis that because the gonopodium is critical to fitness there will not be significant differences in gonopodium shape between the two gonopodial morphs in this species. My results are consistent with this prediction, though I found that gonopodium shape did differ with gonopodium size.

The phylogeny of the turtle genus Pseudemys is poorly understood. In Virginia, many turtles have been found with indicator traits of both eastern river cooters (Pseudemys concinna concinna) and northern red bellied cooters (Pseudemys rubriventris). This study explores morphological evidence for hybridization between the two species across three riverine sites in east central Virginia. Museum voucher groups for each species were analyzed for relative shell height and plastron length. The shape of the plastral scutes and upper jaw were analyzed using landmark-based morphometric software. These metrics were compared with measurements taken from 188 field-caught Pseudemys specimens. Across phenotypic metrics, field specimens resembled northern red bellied cooters. Geometric morphometric analysis showed extreme variation. Thirteen field specimens exhibited indicator traits of both species. Because species boundaries do not appear to be well-resolved using accepted phenotypes and morphometrics, we suggest that additional research utilizing molecular methods and genetic analysis be conducted.

<p>In terms of forensic entomology, one area that is scrutinized most is the estimation of a minimum post mortem interval (mPMI) based on insects that are present at a crime scene. The identification of the insects found at the scene if the first step to calculate a mPMI. However, currently there are no methods that can present the courts with accurate statistical error rates in identification, because the current methods are reliant on an expert’s use of a morphological key to identify the specimen, and this identification method does not produce a confidence value. This project aimed to test a method of identification using geometric morphometrics that can produce confidence intervals to provide to the courtrooms. </p><p> Before any identification could start, a standard preservation protocol was developed to ensure that all diagnostic features are preserved, and specimens can be identified in the same way. A clearing method was designed to clear specimens within 24hrs using potassium hydroxide, so they can be dissected and mounted the next day. The dissection of the specimens was a simple six-step procedure to split the mouth hooks, the cuticle and the posterior spiracle. This procedure ensures that all diagnostic features are preserved on a microscope slide.</p><p> With all of the features preserved, the microscope slide is photographed for storage and an investigator can perform geometric morphometrics to identify the insect. This study tested the application of geometric morphometrics to distinguish between three genera of Calliphoridae (<i>Calliphora</i>,<i>Lucilia</i>, <i>Phormia</i>), from three locations in the US (Delaware, Indiana, California). Results showed significant (p-value: <0.05) variation in shape among all genera. When genera were tested for shape differences based on location, these variations were also significant (p-value: <0.05). The implication of these results is that enough shape difference exists to distinguish between these genera and to distinguish between populations.</p>

Today’s highly endangered orangutan populations of Sumatra and Borneo offer but a glimpse into the taxonomic diversity and vast regional distribution enjoyed by orangutans and their great ape relatives in East Asia over the past 2.5 million years—a time when tropical forest pongine habitats stretched from Java to southern China. In addition to the giant terrestrial ape Gigantopithecus, other great ape genera have been proposed to have existed within this hominid community. The taxonomic diversity of this great ape faunal array is even further complicated when the purported presence of hominins at Early Pleistocene sites older than 1.85 Ma is considered. Highly acidic, the jungle floors of East Asia are notoriously bad at fossil preservation decomposing skeletal and dental evidence quickly. Fortunately, ph-neutral limestone caves have acted to offset these forces. The outcome of this peculiar taphonomy has left us with many teeth, but very little bone. With only unassociated fossil dentition to work with, modern geometric morphometrics offers scientists one of the few cutting-edge tools capable of systematically assessing this material reliably. This dissertation applies modern geometric morphometric statistical analysis to over two thousand fossil hominid teeth (Appendix A) from the Quaternary of southern China and Southeast Asia, which offers unique insight into the taxonomic diversity present in this sole Pleistocene great ape community. This study provides a much clearer understanding of the composition, paleoecology, and regional distribution of Pleistocene great ape communities of East Asia. Concordant with previous research, the main study and pilot study conducted in this dissertation showed Homo sapiens to always be morphologically and statistically distinct from extant and fossil orangutans. In turn, Pongo pygmaeus and Pongo abelii were continuously shown to be distinct from each other as well as from fossil Pongo groups. This investigation refutes hominin assignments for several teeth previously placed within early East Asian hominins (showing them to be orangutans instead) but supports the hominin status of the Jianshi upper third premolar. In combination with a published age of 1.95–2.15 million years (Ma), the hominin assignment reaffirmed here for the Jianshi dentition originally classified as human by Liu, Clarke, & Xing (2010) may offer a challenge to evolutionary models that recognize the 1.85 Ma Dmanisi hominins as the earliest hominins outside of Africa. This fact is often lost on most contemporary scientists due to their preoccupation with the 2.5 Ma Longgupo mandibular fragment, once thought to be a hominin but now assignable to an ape. Like the Jianshi upper third premolar, it is also based on a single specimen (in this case, a mandibular fragment). This dissertation supports the existence of Ciochon’s (2009) “mystery ape”. It refutes Schwartz et al., (1995) multiple Vietnamese Pongo taxa, including the proposed genus “Langsonia,” which is reassigned here to Pongo or the “mystery ape,” while placing Vietnamese fossil orangutans into either Pongo weidenreichi or Pongo devosi. Teeth from the Ralph von Koenigswald collection originally assigned to “Hemanthropus” were also determined to be representative of either the “mystery ape” or Pongo. Indeterminate “hominin” teeth were assignable to either Homo erectus, Homo sapiens, or Pongo only; no evidence was found for any other types of hominin species present in the collections examined for this study.

In this study, the corallite shapes of three species of the scleractinian genus Undaria from the Yague group, Dominican Republic, were examined through a period of time stretching from 6.4 mya to 3.4 mya, a total of 3.0 ma. Corallite shape was measured using 3 dimensional landmarks and manipulated using the well established procedures of geometric morphometrics. Differences in shape and size through time were examined using a variety of tools, including canonical variates analysis, principal components analysis, least squares regression, partial least squares regression, and a variety of evolutionary model fits. Evolutionary model fits were used to test three models against the shape and size variables: general random walk, which models a directional change through time; unbiased random walk, which models random change through time; and stasis, which models stability through time. Stasis is the most common parameter through time, supported in 9 of 15 (60%) of cases, while the unbiased random walk was supported 6 of 15 times. While there was a significant change in one species associated with environmental variables, those variables were also correlated with time and no causal relationship can be reached.

Les poissons demoiselles (Pomacentridae) représentent lune des familles les plus importantes des récifs coralliens ; du point de vue du nombre despèces (> 350) et de leur abondance. Malgré cette importance, très peu détudes ont abordé leur diversité trophique et morphologique. Comme la majorité des poissons coralliens, les demoiselles possèdent un cycle de vie complexe divisé en deux phases : (1) une phase larvaire pélagique et océanique potentiellement dispersive et (2) une phase juvénile et adulte sédentaire associée à lhabitat corallien. La fin du stade larvaire coïncide avec la colonisation du récif. Le milieu océanique offre un habitat relativement homogène pour toutes les larves de Pomacentridae et celles-ci se nourrissent exclusivement de copépodes planctoniques. Au contraire, le récif propose une grande variété dhabitats et de ressources alimentaires. Au cours de leur ontogénie, les demoiselles subissent donc un changement de mode de vie qui doit saccompagner de modifications morphologiques, physiologiques et comportementales pour optimiser leur survie dans chaque environnement. La présente thèse a pour premier objectif de tester lhypothèse selon laquelle la plus grande diversité trophique attendue au stade adulte saccompagne dune plus grande disparité (mesure de la diversité morphologique au sein dun taxon) que chez les larves. Répondre à cet objectif a nécessité dorganiser la recherche selon trois axes. Premièrement, Lanalyse des contenus stomacaux et des isotopes stables du carbone et de lazote chez treize espèces a permis de mettre en évidence trois comportements alimentaires : (1) les « pelagic feeders » qui se nourrissent presquexclusivement de copépodes planctoniques, (2) les « benthic feeders » qui sont des espèces principalement herbivores broutant des algues filamenteuses et (3) un groupe intermédiaire incluant des espèces qui se nourrissent en proportions variables dans le compartiment pélagique et benthique (ex : copépodes planctoniques et benthiques, petits invertébrés vagiles et sessiles, algues filamenteuses). La littérature signale en plus deux demoiselles spécialisées dans la consommation exclusive de polypes de coraux. Deuxièmement, une étude écomorphologique a caractérisé la diversité du squelette céphalique chez les adultes. Les variations de forme de quatre unités du squelette céphalique (le neurocrâne, lunité « suspensorium et opercule », la mandibule et le prémaxillaire) ont été explorées au moyen de la morphométrie géométrique chez quatorze espèces adultes montrant des régimes alimentaires différents. Les résultats révèlent un parallélisme entre la diversité du squelette céphalique et la diversité des régimes alimentaires présent au stade adulte. Dune manière générale, les demoiselles planctonophages possèdent des caractères squelettiques optimisant la prise de nourriture par aspiration (ex : hauts suspensoria et opercules, une large crête supraoccipitale, des mandibules courtes formant une petite bouche). Les espèces brouteuses montrent des pièces squelettiques plus robustes (ex : mandibules hautes et massives, hyomandibulaires larges). Parmi les espèces zooplanctonophages, Chromis viridis et C. acares montrent une morphologie céphalique assez divergente de celle des autres. Leurs caractéristiques squelettiques laissent supposer un mode de prise de nourriture où le poisson capture sa proie en nageant vers elle bouche ouverte (type « ram-suction feeder »). La dentition buccale nest pas toujours corrélée au régime alimentaire. Troisièmement, lontogénie post-colonisation et la variation du niveau de disparité squelettique ont été étudiées et comparées chez huit espèces représentant un échantillon complet de la diversité trophique de la famille. Après la colonisation, les demoiselles subissent des allométries de croissance importantes (40 à 87% des variations de forme). La disparité morphologique est plus grande au stade adulte quau stade de la colonisation pour chaque structure squelettique céphalique. Lensemble des paramètres développementaux étudiés ont subi des changements évolutifs. À la colonisation, les formes larvaires sont déjà spécifiques, probablement à cause de différences dans la durée de vie larvaire pélagique des espèces. Laugmentation de la disparité au cours du développement post-colonisation est essentiellement due à la divergence des patrons allométriques. La longueur des trajectoires ontogénétiques et les vitesses de développement apparaissent comme deux facteurs moins variables. Dune manière générale, peu de liens existent entre les données phylogénétiques ou écologiques (régime, durée de vie larvaire,) et les paramètres développementaux. La diversité du genre Dascyllus illustre des cas de gigantisme. Les méthodes de morphométrie géométrique montrent que les petites espèces et les espèces géantes partagent les mêmes trajectoires ontogénétiques pour le neurocrâne et la mandibule. Au sein de ce groupe, lapparition despèces de grande taille au cours de lévolution résulterait de processus hétérochroniques. La morphologie céphalique larvaire suggère une prise de nourriture de type « ram/suction feeding ». Chez toutes les espèces étudiées, les patrons allométriques révèlent une optimisation du système de prise de nourriture par aspiration au cours du développement. Les demoiselles acquièrent au cours de leur croissance des joues et de opercules proportionnellement plus hauts, une crête supraoccipitale plus grande, des mandibules plus courtes et un processus ascendant du prémaxillaire plus long. Chez les espèces herbivores, dautres changements de forme sont liés à lacquisition de capacités de morsure et de découpe. Par exemple, les mandibules et les suspensoria deviennent plus massifs.

This thesis presents an investigation into Paleoindian projectile-point morphology. A goal of this research is to determine if evidence of a normative cultural manufacturing protocol can be identified on Clovis projectile points which can then be used to address research questions concerning Clovis point variability, and ultimately, the spread of this tool-form across North America. This paper addresses obstacles to behavioral investigations of stone tool morphology such as the effects of resharpening and raw material type on tool shape. I argue that a culturally normative process of manufacture was maintained throughout the life-history of Clovis projectile points which translated into a specific shape maintained to the time of exhaustion and discard. As an analytical tool, this study utilizes the geometric morphometric method to retain the geometry of each artifact throughout analysis by focusing on spatial covariation among landmarks uniformly found on each tool. This thesis investigates variability in 123 fluted projectile points from 23 archaeological sites in North America which met criteria meant to control for security of context in the archaeological record. Principle components describing the shape-variability inherent in this data-set were generated using geometric morphometrics and multivariate statistical analyses were employed to identify major factors of variability. This research concluded that Clovis projectile-point shape was determined by normative cultural behavior maintained throughout the life of the artifact and not the result of raw material type or resharpening processes. Therefore, the projectile-point variability found to be geographically patterned provided evidence of Paleoindian movement and the spread of tool form. Multivariate analysis of variance determined that a regional trend in variability was present. The distribution of within-site variance suggested that artifacts from sites in the West were very homogeneous while artifacts from Eastern sites were more variable. The multivariate cluster and discriminant function analyses also demonstrated a closer affinity between artifacts in the Southwest and Northwest than either has with the Northeast. The similarities in projectile point morphology between the Southwest and Northwest regions suggest movement beginning with a Southwest point of origin from which Pleistocene peoples may have carried their fluted point technology north and east.

BACKGROUND: Orthodontists rely heavily on cephalometric analysis to assess growth potential and direction. Geometric morphometrics examines shape and can help the clinician reach more accurate diagnoses and predict future growth. PURPOSE: The aims of this study are: 1) Determine principle components describing craniofacial shape changes; 2) Assess shape changes in growing subjects; 3) Develop a model for craniofacial growth prediction using geometric morphometrics. RESEARCH DESIGN: The Cranial base, maxilla and mandible were digitized on 330 lateral cephalograms from ages 6-16 (n=33). Generalized Procrustes analysis was performed on the longitudinal data sample. Principle Component, Discriminant Function and Two-Block Partial Least Squares analysis were assessed against changes in individual structures to determine if changes in the maxillary, mandibular or cranial base are related to changes in shape of the overall craniofacial form. RESULTS: PCA shows that the first six principle components account for 67.7 – 77.0% of the observed shape variance in each region and 56.0% of the whole form. Multivariate regression analysis predicts the shape of the entire craniofacial complex at 16 years old based on the shape observed at 6 years old with 94% certainty. An intraclass correlation coefficient of 0.98 confirms reliability. CONCLUSION: Morphometric analyses indicate that changes in maxillofacial morphology during skeletal maturation are linear. The shape of the craniofacial complex does not change significantly and growth pattern is maintained. Our model can predict the craniofacial shape at 16 years of age based on the shape observed at 6 years of age.

Recent inquiry into the nomenclature of several species within Spinocyrtia has led to questions concerning name applicability and validity, particularly whether Delthyris granulosa and Spinocyrtia (Spirifer) granulosa are synonymous. This study utilized two-dimensional outline landmark analysis, a form of geometric morphometric analysis, to evaluate interspecific variation among these species. I took over a thousand photographs of over a hundred specimens of brachiopods belonging to the family Spinocyrtiidae. Ninety-six specimens originated from the Givetian outcrop belt of New York state, three were from northwestern Ohio, there was single Canadian specimen, and there was a single German specimen. The results from these analyses indicate that the mophospaces of Spinocyrtia (Spirifer) congesta, S. (Spirifer) granulosa, and S?. (Spirifer) marcyi are statistically (p < 0.05) distinct from one another.

This study utilizes two-dimensional geometric morphometric techniques to address molar shape variation in extinct and extant prosimians using the relative orientation of selected homologous molar landmarks (paraconid, protoconid, metaconid, entoconid, hypoconid, hypoconulid, metaconulid, and the intersection of the cristid obliqua with the protolophid). Molar shape was studied using Thin-Plate Splines analysis to explore variation using shape variables simultaneously, rather than by comparing inter-landmark distances, as in traditional studies. The sampled extant taxa included members from the Malagasy lemur families Lepilemuridae, Lemuridae, and Indriidae, as well as Asian Lorisidae. Extant taxa were categorized using taxonomic, as well as dietary, categories to determine if intra-sample variation was correlated with either category. Results suggest that frugivores (and gramnivores) generally exhibit a relatively wide anterior talonid basin and little trigonid torsion (observed as the angle of the protolophid relative to the long axis of the molar). Folivores, on the other hand, generally exhibit a constricted anterior talonid and higher degrees of trigonid torsion. Lorisid omnivores were found to exhibit constricted anterior talonids, but little trigonid torsion. The Thin-Plate Splines technique was also applied to a sample of three extinct adapiform families: Notharctidae, Adapidae, and Sivaladapidae. These comparisons were aimed at further exploration into dietary adaptation and diversity in extinct prosimians, and to specifically address the paleobiology of the Asian sivaladapids. Like their extant counterparts, adapiforms generally varied also in the relative orientation of the trigonid basin and in the dimensions of the talonid basin. In addition, the relative location of the paraconid also varied significantly within several adapiform families. Results of this study specifically highlight shape variation within several prosimian lineages, suggesting that a broader perspective of morphological diversity can be appreciated through analyzing adaptation within a particular family. For the sivaladapid genera, Sivaladapis and Hoanghonius, in particular, as well as North American Notharctidae, a molar shape similar to Nycticebus (an Asian loris) was noted. For Adapidae, a similarity with extant indriids was revealed. In summary, it is suggested here that multiple lines of morphological evidence should be employed to gain the broadest perspective of extinct primate adaptation.