FUNCTION AND EVOLUTION OF PLUMAGE TRAITS IN TROGONS (AVES TROGONIFORMES), AND THE IMPORTANCE OF PARAMETERIZATION IN VISUAL MODELS

In this dissertation, I investigated the function and evolution of plumage-based visual signals in trogons (Trogoniformes), and assessed the influence of individual parameters in the receptor-noise model of colour discriminability. In Chapter 2, I investigated the function of tail raising in the elegant trogon. For this purpose, I used observational and experimental data collected in Costa Rica. Results demonstrated that tail raising in the elegant trogon is a multifunctional signal that targets both conspecifics and heterospecifics. Specifically, trogons used this behaviour during intra and intersexual interactions, and the experiment confirmed that tail raising is a pursuit-deterrent signal. In Chapter 3, I experimentally tested which plumage patches are used in species recognition in two species of trogons: the black-headed trogon, which is sympatric with a similar-looking congener, and the elegant trogon, which is not sympatric with a similar-looking congener. The results suggested that while both species use the back and belly colour as specie- recognition traits, the black-headed trogon but not the elegant trogon also assessed the tail banding pattern. In Chapter 4, I investigated the relationship between sympatry and plumage divergence in the genus Trogon. My results demonstrated that Trogon taxa diversified more rapidly, and that plumage trait divergence increased with sympatric overlap in South American but not Central American taxa. Together, my findings suggested that the rapid colonization of South America following the Great American Interchange resulted in reinforcement through character displacement or trait sorting. In Chapter 5, I investigated how dichromatism scores are influenced by individual parameters of the receptor-noise model of chromatic contrast threshold, using an avian-based tetrachromatic approach. I systematically tested parameter values for ambient light environment, photoreceptor sensitivities and densities, transmission properties of the ocular media and oil droplets, and compared the sensory experience of species for which the visual system has been fully characterized. My results demonstrated that oil droplet characteristics, photoreceptor densities, and the sensitivity of the SWS1 photoreceptor (ultraviolet sensitive or not) had the most influence on dichromatism scores. I encourage the complete characterization of visual systems when possible, and my results will inform researchers when making inferences about tetrachromatic visual models

Social networks Big Data: Personality traits as an explanatory variable in GLM models for insurance claim counts

Treballs Finals del Màster de Ciències Actuarials i Financeres, Facultat d'Economia i Empresa, Universitat de Barcelona, Curs: 2016-2017, Tutora: Catalina Bolancé LosillaIn an industry such as the insurer, highly atomized and competitive, where price comparison engines allow customers to have greater control over information in decision-making; insurance companies are investing great part of their efforts to find new formulas that improve customer loyalty. In that sense, using Big Data generated from social networks such as Facebook, Twitter or YouTube, to know the policyholder’s personality, can be used as a strategy that allow companies to compete through personalized service and more competitive premiums. In this study, I analyze the framework to introduce personality as an explanatory variable in Generalized Linear Models for claims count and try to found out any empirical evidence of the relation between personality traits and insurance claims

Pola Interaksi Guru Dan Siswa Tunanetra Dalam Pembelajaran Matematika Di Smplb a Ykab Surakarta (Studi Kasus Pada Siswa Kelas IX Smplb a Ykab Surakarta Semester Ganjil Tahun Pelajaran 2012/2013)

With visual impairment in mathematics teaching learning on a conceptual and procedural knowledge in class IX SMPLB A YKAB Surakarta. This research was a qualitative case study, investigating deeply about the interaction of the teacher and the students in order that the interaction pattern can be described in the mathematics teaching learning. The subjects of this research were a mathematics teacher and all students of class IX SMPLB A YKAB Surakarta. The data in this study were in the form of teacher and students interactions obtained from transcriptions of the teaching learning recordings during twice observations. The transcription results were the teacher and the students\u27 conversations that are further reduced in order to obtain certain conversation related to the teaching learning of conceptual and procedural knowledge. Furthermore, labeling speech act and speech interaction was conducted in the conversation of conceptual and procedural teaching learning. Based on the labeling, speech interaction were categorized into three, namely: 1) speech interaction that was begun with speech act of giving information (BIn), 2) speech interaction that was begun with speech act of performing information (UIn), and 3) speech interaction that was begun with speech act of stimulating information (TIn). Each of the categories was analyzed so that the subjects that are interacting can be examined. The result of the analysis became the data of teacher and students interaction. The technique used to validate the data was time triangulation done by matching the data of the teacher and the students\u27 interaction taken from the first observation and the data of the teacher and the students\u27 interaction taken from the second observation.The results of the matching process were used to describe the interaction pattern. The findings of this research were: 1) the interaction pattern of the teacher and the students with visual impairment in mathematics teaching learning on a conceptual knowledge in class IX SMPLB A YKAB Surakarta was a two-way interaction pattern with inter-students interactions.Two-way interactionwith studentteachersis dominatedby theactivities ofthe teacherto giving information (BIN) and the performing information (TIN) to the students. While theinteractionbetween studentsis dominatedbythe activities ofthe studentsto performanceinformation(UIN). 2) the interaction pattern of the teacher and the students with visual impairment in mathematics teaching learning on a procedural knowledge in class IX SMPLB A YKAB Surakarta was a multiple-way interaction pattern (optimal result). Teacherinteractionwith studentsis dominatedby theactivities ofthe teacherto giving information(BIN), andstimulating information(TIN) to the students. Whilestudent interactionwith studentsspreadis dominated bythe performanceof information(UIN)

Red fluorescence of the triplefin Tripterygion delaisi is increasingly visible against background light with increasing depth

The light environment in water bodies changes with depth due to the absorption of short and long wavelengths. Below 10 m depth, red wavelengths are almost completely absent rendering any red-reflecting animal dark and achromatic. However, fluorescence may produce red coloration even when red light is not available for reflection. A large number of marine taxa including over 270 fish species are known to produce red fluorescence, yet it is unclear under which natural light environment fluorescence contributes perceptively to their colours. To address this question we: (i) characterized the visual system of Tripterygion delaisi, which possesses fluorescent irides, (ii) separated the colour of the irides into its reflectance and fluorescence components and (iii) combined these data with field measurements of the ambient light environment to calculate depth-dependent perceptual chromatic and achromatic contrasts using visual modelling. We found that triplefins have cones with at least three different spectral sensitivities, including differences between the two members of the double cones, giving them the potential for trichromatic colour vision. We also show that fluorescence contributes increasingly to the radiance of the irides with increasing depth. Our results support the potential functionality of red fluorescence, including communicative roles such as species and sex identity, and non-communicative roles such as camouflage

Baseline corticosterone does not reflect iridescent plumage traits in female tree swallows

The production of high quality secondary sexual traits can be constrained by trade-offs in the allocation of energy and nutrients with other metabolic activities, and is mediated by physiological processes. In birds, the factors influencing male plumage quality have been well studied; however, factors affecting female plumage quality are poorly understood. Furthermore, it remains uncertain which physiological traits mediate the relationship between body condition and ornaments. In this three-year study of after-second-year female tree swallows (Tachycineta bicolor), we investigated (1) the relationship between baseline corticosterone near the end of the brood-rearing period (CORTBR) and feather colour characteristics (hue, saturation, brightness) the following year, and (2) the relationship between baseline corticosterone measured during incubation (CORTI) and brood rearing (CORTBR), and feather colour in the same year. To control for reproductive effort, we included reproductive parameters as covariates in all analyses. In this first study between CORT and the plumage colour characteristics of a species bearing iridescent feathers, we did not find any relationship between CORTBR and the colour of subsequently-produced feathers, nor did we find any relationship between CORT and the colour of feathers displayed during that breeding season. If CORT levels at the end of breeding carry over to influence the immediately subsequent moult period as we expect, our results generally indicate that structural plumage quality may not be as sensitive to circulating CORT levels compared to carotenoid-based colouration. Future studies, particularly those employing experimental manipulations of CORT during moult in species with iridescent traits, are necessary to fully determine the role glucocorticoids play in mediating the quality of secondary sexual characteristics

Optic-nerve-transmitted eyeshine, a new type of light emission from fish eyes

Background: Most animal eyes feature an opaque pigmented eyecup to assure that light can enter from one direction only. We challenge this dogma by describing a previously unknown form of eyeshine resulting from light that enters the eye through the top of the head and optic nerve, eventually emanating through the pupil as a narrow beam: the Optic-Nerve-Transmitted (ONT) eyeshine. We characterize ONT eyeshine in the triplefin blenny Tripterygion delaisi (Tripterygiidae) in comparison to three other teleost species, using behavioural and anatomical observations, spectrophotometry, histology, and magnetic resonance imaging. The study’s aim is to identify the factors that determine ONT eyeshine occurrence and intensity, and whether these are specifically adapted for that purpose. Results: ONT eyeshine intensity benefits from locally reduced head pigmentation, a thin skull, the gap between eyes and forebrain, the potential light-guiding properties of the optic nerve, and, most importantly, a short distance between the head surface and the optic nerves. Conclusions: The generality of these factors and the lack of specifically adapted features implies that ONT eyeshine is widespread among small fish species. Nevertheless, its intensity varies considerably, depending on the specific combination and varying expression of common anatomical features. We discuss whether ONT eyeshine might affect visual performance, and speculate about possible functions such as predator detection, camouflage, and intraspecific communication. Electronic supplementary material The online version of this article (doi:10.1186/s12983-017-0198-9) contains supplementary material, which is available to authorized users

Data from: Age-related prenatal maternal effects and postnatal breeding experience have different influences on nestling development in an altricial passerine

Reproductive success and nestling performance are related to the age of parents across several vertebrate taxa. However, because breeding experience and prenatal maternal investment in reproduction often covary, the source of these age-related differences can be difficult to determine. In this study, we evaluated the influence of prenatal maternal effects and postnatal breeding experience on the performance of nestling tree swallows Tachycineta bicolor by conducting a carefully controlled partial cross-fostering experiment. We swapped half-broods of nestlings between the nest of a young first-time breeding female and the nest of a female known to have previously raised and fledged young. Our manipulation did not influence the within-brood nestling hierarchies, and controlled for the effects of egg laying order. We found that nestlings of older females were heavier just prior to fledging regardless of the breeding experience of the attending female. In addition, fledglings raised by experienced females grew their flight feathers faster, and had greater probability of fledging. Our study demonstrates that prenatal investment in reproduction by older females can have long-term consequences on nestling mass, and suggests limited potential for compensatory mass gains prior to fledging. Because our analyses controlled for feeding rates, our results also suggest that foraging quantity and quality are not the only benefits nestlings gain by being raised by an experienced female

Sympatric black-headed and elegant trogons focus on different plumage characteristics for species recognition

The ability of individuals to distinguish conspecifics from similar-looking congeners has important evolutionary consequences, yet few studies have determined which specific visual characteristics are used for species recognition, and whether closely related species use the same characteristics. In particular, sympatry with similar-looking congeners may influence which traits are important in species recognition. We presented elegant trogons, Trogon elegans, and black-headed trogons, Trogon melanocephalus, with models that closely resembled conspecifics and models that differed in either the colour of the belly, the colour of the upperparts or the tail-barring pattern, while broadcasting species-specific songs. Elegant trogons showed significantly more aggression towards the conspecific and tail models, suggesting that belly and back colour, but not tail-barring pattern, are important for species recognition in this species. In contrast, the black-headed trogon approached all models very closely, except for the conspecific model. We interpret this counterintuitive behaviour as reluctance to approach an unknown conspecific, suggesting that all three plumage traits are important for species recognition in black-headed trogons. Because the elegant trogon is not sympatric with a similar-looking congener, we argue that they may lack the ability to discriminate fine-barring tail differences or overlook this trait. Sympatry with the similar-looking violaceous trogon may have influenced species recognition in black-headed trogons, favouring the use of all three plumage characteristics, including tail-banding patterns, which differ between these species. Alternatively, it is possible that incongruent stimuli are attended to differently, with elegant trogons focusing on the acoustic traits and black-headed trogons focusing on visual cues. Nevertheless, our study provides the first experimental evidence that specific plumage patches are used for species recognition and that closely related species may use different traits for species recognition. Our findings also suggest that the presence of a similar-looking congener can influence which traits are important in species recognition

A multifunctional visual display in elegant trogons targets conspecifics and heterospecifics

Avian visual displays often target either conspecifics or heterospecifics, but few visual displays have been described where both conspecifics and heterospecifics are the intended receivers. In this study, combining observational and experimental approaches, we present evidence that a tail-raising display performed by the elegant trogon (Trogon elegans) is used in multiple contexts and is directed at conspecifics and heterospecifics. We observed tail-raising displays toward conspecifics in both intersexual and intrasexual contexts, as well as toward heterospecifics. Displays performed toward heterospecifics were directed at humans, monkeys, or birds of prey, all of which could have been perceived as potential predators. We experimentally tested the possible functions of tail-raising behavior in the presence of a predator by presenting elegant trogons with models of a natural predator and a nonthreatening control. Tail-raising displays were much more likely to occur when trogons were in the presence of a predator model (48% of trials) than a control model (6% of trials). The presence of conspecifics did not influence tail-raising propensity (conspecifics present: 44% of trials and conspecifics absent: 50% of trials). Our results suggest that tail raising in trogons is a multifunctional visual display that may function as an intersexual and intrasexual conspecific signal as well as a pursuit-deterrent signal directed at predators