The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 13, 2009). Thesis advisor: Dr. Craig T. Palmer. Includes bibliographical references.

Social projection is the tendency to project one's own characteristics onto others. This phenomenon can potentially explain cooperation in prisoner's dilemma experiments and other social dilemmas. The social projection hypothesis has recently been formalized for symmetric games as co-action equilibrium and for general games as consistent evidential equilibrium. These concepts have been proposed to predict choice behavior in experimental one-shot games. We test the predictions of the co-action equilibrium concept in a simple binary minimizer game experiment. We find no evidence of social projection.

No description available.

La préhension manuelle, impliquée dans l’acquisition de nourriture et la locomotion, est commune à tous les primates. Toutefois, les mécanismes de son émergence et de son évolution restent encore à élucider. Quels sont les facteurs 1) écologiques (propriétés de la nourriture et du substrat) conduisant à une plus grande utilisation de la main chez les premiers primates et 2) fonctionnels (posture corporelle, cinématique du membre supérieur) impliqués dans l’évolution de la préhension des primates?Afin d’apporter des éléments de réponse, cette thèse a pour objectif de déterminer les stratégies comportementales et cinématiques de la préhension non contrainte d’espèces représentatives des grands groupes phylogénétiques primates (microcèbe, lémur catta, capucin, gorille, chimpanzé, humain).Tout d’abord, les stratégies comportementales du microcèbe, présentant des convergences avec les premiers primates, suggèrent que l’arboricolie et l’omnivorie ont joué un rôle important dans l’émergence des capacités de préhension des primates. Ensuite, l’analyse de la préhension du gorille et de l’humain montre une influence limitée des postures corporelles sur les stratégies articulaires du membre supérieur. Enfin, la comparaison de toutes les espèces montre que certains invariants cinématiques de la préhension liés à la vitesse du poignet existent indépendamment des espèces et que d’autres semblent être lié au comportement des espèces. En outre, deux stratégies articulaires divisent les espèces favorisant les rotations (gorille et chimpanzé) de celles privilégiant les flexions-extensions (lémur, capucin, humain). Ces stratégies articulaires semblent avoir évolué indépendamment de leurs capacités préhensiles.L’ensemble de ces résultats est discuté au regard des données comportementales et fonctionnelles connues et confronté aux théories actuelles sur l’origine et l’évolution de la préhension. / Manual prehension, involved in food acquisition and locomotion, is common to all primates. However, the mechanisms of its emergence and evolution still remain to be elucidated. This prompts questions such as 1) what are the ecological factors (food and substrate properties) leading to an increase of the use of the hand in early primates, and 2) what functional factors (body posture, kinematics of the forelimb) are involved in the evolution of prehension in primates?The thesis project aims to determine the behavioural and kinematic strategies of unconstrained prehension in representative species of the major lineages of primates (the mouse lemur, lemur catta, capuchin, gorilla, chimpanzee, human).The behavioural strategies of the mouse lemur, convergent on early primates, suggest that arboreality and omnivory have played an important role in the origin of prehensile abilities in primates. The analysis of prehension in gorillas and humans shows a limited influence of body posture on the angular joint excursions and kinematic strategies. A comparison of all the species reveals that some kinematic invariants in the wrist velocity profile exist, independent of the species. Yet others appear to be related to the specific behaviour of the species. Moreover, two joint motion strategies divide the species, one favoring the rotations (gorillas and chimpanzees) and one involving more flexion-extension movements (lemurs, capuchins, humans). These joint motion strategies seem to have evolved independently of grasping ability.The results are discussed in the context of current work and theories on the origin and the evolution of prehension in primates.

The emergence of life depended on the ability of the first biopolymer populations to thrive and approach larger population sizes and longer sequences. The evolution of these populations likely occurred under circumstances under which Muller's Ratchet in synergism with random drift could have caused large genetic deterioration of the biopolymers. This deterioration can drive the populations to extinction unless there is a mechanism to counteract it. The effect of the mutation rate and the effective population size on the time to extinction was tested on clonal populations of B16-19 ligase ribozymes, evolved with the continuous evolution in vitro system. Populations of 100, 300, 600 and/or 3000 molecules were evolved with and without the addition of Mn(II). The times to extinction for populations evolved without Mn(II) were found to be directly related to the effective size of the population. The small populations approached extinction at an average of 24.3 cycles; while the large populations did so at an average of 44.5 cycles. Genotypic characterization of the populations showed the presence of deleterious mutations in the small populations, which are the likely cause of their genetic deterioration and extinction via mutational meltdown. These deleterious mutations were not observed in the large populations; in contrast an advantageous mutant was present. Populations of 100 and 3000 molecules were evolved with Mn(II). None of the populations showed signs of genetic deterioration nor did they become extinct. Genotypic characterization of the 100-molecule population indicated the presence of a cloud of mutants closely genetically-related, forming a "quasispecies" structure.. The close connectedness of the mutants facilitates the recovery of one from another in the event of being removed from the population by random genetic drift. Thus, quasispecies shift the target of selection from individual to group. The total fitness of the molecules was measured by identifying the fitness component of the system that effect the ligase replication cycles: ligation, reverse transcription and transcription. It was found that the strength of the three components of fitness varied and that each one has a differential effect in the total absolute fitness of the ligases.

The butterfly genus Heliconius has an unusually long lifespan (six to eight months compared to only several weeks) and the unique ability to feed on pollen. The additional amino acids provided by a pollen diet seem intrinsically tied to longer lifespan in Heliconius. Because of these traits, Heliconius may be a valuable model species for future aging studies. As a preliminary analysis, we investigated differences in gene evolution between Heliconius and seven short-lived butterflies. We observed that the Heliconius genes had significant differences in evolutionary rates, in the direction of selection, and in the amounts of site-specific positive selection compared to the short-lived butterflies. We also investigated functional differences in gene complements between the Heliconius and short-lived butterflies but found only small differences. With this research, we present exploratory evidence supporting differences in gene evolution of the Heliconius to establish targets for future analysis of Heliconius as models for aging.

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No description available.

The substantial difference in ionic concentration and osmotic pressure between marine and freshwater environments creates a barrier to dispersal that relatively few metazoan lineages have been able to cross during the evolution of life on earth. Only about half of animal phyla have representatives in both marine and freshwater environments. Even within the phyla that contain freshwater species there are often large clades that continue to be exclusively marine. Interestingly, though, among some of the clades with freshwater species, this transition has occurred repeated. In order to begin to better understand the mechanisms that have allowed some marine lineages to colonize freshwater environments, I investigated the role of gene duplications in this process. First, using published annelid genomes I compared the gene copy number of the Na+/K+-ATPase alpha subunit gene family, the plasma membrane Ca2+ ATPase (PMCA) gene family, and the sarcoplasmic reticulum Ca2+ (SERCA) gene family between marine and freshwater species. I also used gene tree/species tree reconciliation to infer the time of those duplication events. There was a burst of duplications of the Na+/K+-ATPase alpha subunit gene that coincides with the colonization of freshwater habitats by annelids. The evidence of such a burst of duplications for the PMCA or SERCA gene families is inconclusive. Next, in order to increase the sample size and look for more gene families that were involved in the transition to freshwater habitats I downloaded 11 genomes from spiralian animals. I looked for specific gene families that showed a significant increase in size in freshwater species compared to marine species and identified the Na+/K+-ATPase alpha subunit gene family among others. I also used GO enrichment analysis to determine which GO terms were overrepresented in gene families that expanded along freshwater lineages and found terms related to ion transfer to be most common. Finally, I examined available mollusk genomes to compare size of the gene families of interest from the spiralian analyses between marine and freshwater mollusk species. I again found the Na+/K+-ATPase alpha subunit gene family to show a significant increase in size in the freshwater species. How marine animals were able to colonize freshwater habitats is one of the great questions in metazoan evolution and this work represents an important early step in understand this process.

<p>Theories that engender fundamental transformations in our world view seldom come perfect from the outset for two reasons. First, the empirical discoveries and theoretical framework necessary for their full explanatory efficacy are often not yet in place. Secondly, as a consequence of the first, some of the auxiliary theories and assumptions they rely upon are often antiquated and erroneous. For these reasons, anomalies are frequent in scientific theories. In this thesis, I discuss some of the major scientific anomalies, including particularly, the paradox of altruism. I suggest that the paradox of altruism arises because one of the most fundamental Mendelian genetic principles is misapplied. I show that today’s explanatory models err in supposing altruism and selfishness to be genetic allelomorphs. The supposition is inconsistent with the field data on altruism, and entails a logical inconsistency in accounting for the evolution of altruism. Largely, the models that purport to resolve the paradox hinge on the conditional expression of the altruistic gene, a move which I argue contradicts the theoretical assumption that engenders the paradox in the first place. I demonstrate from the empirical data that altruism and selfishness are rather plastic phenotypic expressions of a single genotype. And by supplanting the standard neo-Darwinian assumptions with the principle of phenotypic plasticity, I provide a parsimonious account of the evolution and maintenance of altruism which entails no paradox.</p> / Master of Arts (MA)