The ability to discriminate relative and absolute number has been researched widely in both human and nonhuman species. However, the full extent of numerical ability in nonhuman animals, and the nature of the underlying numerical representation, on which discriminations are based, is still unclear. The aim of the current research was to examine the performance of pigeons and humans in tasks that require the discrimination of relative number (a bisection procedure), and absolute number (in a reproduction procedure). One of the main research questions was whether numerical control over responding could be obtained, above and beyond control by temporal cues in nonhuman animals, and if so, whether it was possible to quantify the relative influences of number and time on responding. Experiment 1 examines nonhuman performance in a numerical bisection task; subjects were presented with either 2 and 6, 4 and 12, or 8 and 24 keylight flashes across three different conditions, and were required to classify these flash sequences as either a “large” or “small” number, by pecking the blue or white key, respectively. Subjects were then tested with novel values within and 2 values higher and lower than the training values. Experiments 2-4 investigate responding in a novel numerical reproduction procedure, in which pigeons were trained to match the number of responses made during a production phase to the number of keylight flashes (2, 4, or 6) in a recently completed sample phase. Experiments 2 and 2A examined discrimination performance when the temporal variables, flash rate and sample phase duration, were perfectly correlated (Experiment 2) or only weakly correlated (Experiment 2a) with flash number. Acquisition of performance in the numerical reproduction procedure was investigated in Experiment 3. For Experiments 1-3, hierarchical regression analyses showed significant control by number over responding, after controlling for temporal cues. Additionally, positive transfer to novel values both within and outside the training range was obtained when the temporal organization of test sequences was similar to baseline training. Experiment 4 investigated the effects of increasing or decreasing the retention interval (RI) on performance in the reproduction procedure, and found this produced a response bias towards larger numbers, contrary to predictions based on previous RI research, and suggested responding was not affected by memorial decay processes. The structure of the representation of number developed by subjects in the bisection and reproduction procedures was investigated using analyses of responding and response variability in Chapters 2 and 6, respectively. Bisection points obtained in Experiment 1 were located at the arithmetic, not geometric mean of all three scales, and coefficients of variation (CVs) obtained in both the bisection and reproduction experiments tended to decrease as flash number increased. Additionally, analyses of the acquisition data found differences in average response number was better fit by a linear than logarithmic scale. These results show that responding did not conform to scalar variability and is largely inconsistent with previous nonhuman research. Together these results suggest responding appeared to be based on a linear scale of number with constant generalisation between values, similar to that associated with human verbal counting, rather than a logarithmic scale with constant generalisation or a linear scale with scalar generalisation between values. Experiment 5 compared pigeons’ and humans’ verbal and nonverbal discrimination performance with numbers 1-20 in analogous bisection, reproduction and report tasks. Human verbal and nonverbal performance in the three tasks was similar and resembled nonhuman performance, although verbal discriminations were more accurate and less variable. The main findings from Experiments 1 and 2A were replicated with humans; bisection points were located at the arithmetic mean, average response number increased linearly as sample number increased, though there was a tendency to underestimate sample number, and decreasing CVs were also obtained for values less than 8. An additional, interesting finding was that CVs showed scalar variability for values greater than 8, suggesting a less exact representation and discrimination process was being used for these values. Collectively, these five experiments provide new evidence for a nonverbal ability to discriminate relative and absolute number with increasing relative accuracy resembling human verbal counting in both human and nonhumans.

Thesis (Ph. D.)--University of Chicago, Dept. of Anthropology. / Includes bibliographical references. Also available on the Internet.

Many animals have ability to percieve the magnetic field of the Earth and use this clue for both orientation and navigation. Yet little is known about physiological mechanism that underlies this sensory ability. Although physiological mechanism still remains unclear, there are three major hypotheses how animals can detect the magnetic field. In this study I focused on the radical pair theory. I analyzed how manipulation of the ambient magnetic field influence the expression of CRY 1, CRY 2 and c-Fos in the pigeon´s retina. I observed in incerased numbers of CRY1, c-Fos and CRY1+c-Fos possitive cells in the ihned nuclear layer (INL) of the retina in animals sbjected to the periodical manipulation of the magnetic field inclination. These data demonstrate that the INL constains a population of neurons that are responsive to magnetic stimuli and strongly suggest that Cry 1 is involved in detection of the Earth magnetic field.

Orientador: Claudia R. B. Haddad / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T21:05:30Z (GMT). No. of bitstreams: 1 Dalio_RonaldoJoseDurigan_M.pdf: 923106 bytes, checksum: 4cfd1d62015260abdbf750e8baf62aa6 (MD5) Previous issue date: 2007 / Resumo: Plantas de Cajanus cajan receberam aplicações de brassinosteróide ou de clotrimazol (inibidor de síntese de brassinosteróides) e foram submetidas à salinidade. O objetivo deste trabalho foi verificar o efeito de duas concentrações de brassinosteróide (1 x 10-7 e 0,5 x 10-9 M) e uma de clotrimazol (1 x 10-4 M), no crescimento, composição bioquímica e transporte de aminoácidos em plantas de C. cajan, submetidas à duas concentrações de NaCl (200 e 400 mM). A salinidade afetou os parâmetros de crescimento (massas frescas e secas, comprimento da parte aérea e da maior raiz, número de folhas, área e suculência foliar), os parâmetros bioquímicos (teores de nitrato, prolina, aminoácidos livres, proteínas totais, açúcares solúveis, sacarose, clorofilas e carotenóides) e o padrão dos aminoácidos transportados. A proporção da maioria dos aminoácidos transportados no xilema diminuiu sob salinidade, com exceção de alanina e serina. A concentração de NaCl a 400 mM provocou as maiores alterações. A aplicação de clotrimazol mostrou-se eficiente na inibição dos efeitos provocados por brassinosteróide na grande maioria dos parâmetros estudados, sob salinidade. Não houve diferença em relação à eficiência das duas concentrações de brassinosteróide utilizadas na maioria dos parâmetros avaliados. A aplicação de brassinosteróide amenizou o efeito do estresse salino na maioria dos parâmetros de crescimento, dos parâmetros bioquímicos e no padrão de aminoácidos transportados em plantas de C. cajan, submetidas à salinidade / Abstract: Plants of Cajanus cajan received applications of brassinosteroid or clotrimazol (brassinosteroids synthesis inhibitor), and were subjected to salt stress. The goal of this study was to verify the effect of two concentrations of brassinosteroid (1.0 x 10-7and 0.5 x 10-9M), and one concentration of clotrimazol (1.0 x 10-4 M) on growth, biochemical composition and transport of amino acids in plants of C. Cajan, cultivated under two concentrations of NaCl (200 and 400 mM). The salt affected growth (fresh and dry mass, shoot length and main root length, number of leaves, leaf area and succulence of leaves) and biochemical parameters (nitrate, proline, free aminoacids, total protein, soluble sugars, sucrose, chlorophylls and carotenoids concentrations), and changed the pattern of amino acids transported. The proportion of most of the amino acids transported in the xylem was reduced by salinity. Alanine and serine were exceptions. The largest alterations were caused by 400 mM of NaCl. Clotrimazol was effective in inhibiting the effects caused by brassinosteroid for the great majority of studied parameters. There was no difference between the two concentrations of brassinosteroid for most parameters evaluated, under salinity. The application of brassinosteroid was effective diminishing the effect of salt on most of the growth and biochemical parameters, and in the patterns of amino acids transported in plants of C. Cajan subjected to salt stress / Mestrado / Mestre em Biologia Vegetal

The ability to discriminate stimuli is the most tested cognitive task in pigeons (Columbia livia f. domestica) within up to now published experiments. Up to now, the influence of personality traits on discrimination has been poorly studied. This thesis looks into the differences in success between individuals and discrimination tasks, and analyzes factors including personality traits influencing the success rate. In this experiment, the total of 72 individual pigeons were tested in four linked tasks: 1) discrimination of black and white screen in the Skinner's box, 2) discrimination of black and white circle patch in the Skinner's box, 3) discrimination of black and white lid in a cage and 4) discrimination of reduced black and white stimuli, placed on a lid, in the cage. The criterium of success was set on 80%. In the Skinner's box, the task were passed by lower number of individuals (6% in first, 20% in second) in comparsion with the cage (48% in third and 50% in fourth). The tasks differed in environment and size of stimuli. It has been determined, that te tested subjecs were able to generalise in the Skinner's box, with an expception when the stimuli was reduced. While testing, all factors that might have influenced the success rate were observed. It has been proved, that the success rate was...

No description available.

L’évaluation de la douleur chez les oiseaux est difficile, puisque la plupart se comportent comme des proies et ont tendance à masquer tout signe extérieur de douleur. Les doses et les drogues utilisées pour traiter la douleur des oiseaux sont la plupart du temps basées sur une extrapolation d’autres espèces, ainsi que sur l’expérience clinique. Peu d’études de pharmacocinétique, d’efficacité et de toxicité sont disponibles dans la littérature. La plupart des études rapportées utilisent des stimuli nociceptifs éloignés des douleurs cliniques, comme les stimuli électriques ou thermiques, qui sont difficilement extrapolables à des situations rencontrées en pratique. L’objectif de notre projet était d’évaluer les effets analgésiques de deux doses de meloxicam chez le pigeon à l’aide d‘un modèle de fracture du fémur. La douleur post-opératoire a été évaluée pendant les quatre premiers jours suivant la chirurgie par trois méthodes : le suivi du poids porté sur la patte opérée comparativement à l’autre patte, quatre différentes échelles descriptives de douleur et la réalisation d’éthogrammes à l’aide d’enregistrements vidéo. L’administration de 0,5 mg/kg PO q12h de meloxicam n’a pas permis de réduire significativement les indicateurs de douleur mesurés comparativement à un groupe témoin recevant de la saline. Les pigeons ayant reçu 2 mg/kg PO q12h de meloxicam ont montré une réduction significative des indicateurs de douleur mesurés par les différentes méthodes. Nos résultats suggèrent que l’administration de 2 mg/kg PO q12h aux pigeons suite à une chirurgie orthopédique procure une analgésie supérieure aux doses actuellement recommandées dans la littérature. / Pain assessment is especially difficult in avian species, since many birds behave as prey and do not show any external signs of distress. Choice of drugs and dosages used in clinical practice are most of the time based on extrapolation from other species and clinical experience. Few pharmacokinetic, efficacy or toxicity research studies are available in the literature. Most of these studies used noxious stimuli, such as electric or thermal stimuli, and results are therefore difficult to extrapolate to clinical pain. The objective of our project was to study the analgesic efficacy of two dosages of meloxicam in pigeons, using a femoral fracture pain model. Postoperative pain was assessed during the first four postoperative days by three different methods: weight bearing load on the fractured limb versus the controlateral limb, four different descriptive pain scales and ethogram realization based on video recordings. Administration of 0.5 mg/kg PO q12h of meloxicam did not show any reduction in the measured level of pain compared to the control group that received saline. However, pigeons that received 2 mg/kg PO q12h showed a significant decrease in their pain levels, with the three different pain assessment methods. Our results suggest that 2 mg/kg can provide a superior level of analgesia compared to the dosages recommended in the current literature, for pigeons that have undergone an orthopedic surgery.

L’évaluation de la douleur chez les oiseaux est difficile, puisque la plupart se comportent comme des proies et ont tendance à masquer tout signe extérieur de douleur. Les doses et les drogues utilisées pour traiter la douleur des oiseaux sont la plupart du temps basées sur une extrapolation d’autres espèces, ainsi que sur l’expérience clinique. Peu d’études de pharmacocinétique, d’efficacité et de toxicité sont disponibles dans la littérature. La plupart des études rapportées utilisent des stimuli nociceptifs éloignés des douleurs cliniques, comme les stimuli électriques ou thermiques, qui sont difficilement extrapolables à des situations rencontrées en pratique. L’objectif de notre projet était d’évaluer les effets analgésiques de deux doses de meloxicam chez le pigeon à l’aide d‘un modèle de fracture du fémur. La douleur post-opératoire a été évaluée pendant les quatre premiers jours suivant la chirurgie par trois méthodes : le suivi du poids porté sur la patte opérée comparativement à l’autre patte, quatre différentes échelles descriptives de douleur et la réalisation d’éthogrammes à l’aide d’enregistrements vidéo. L’administration de 0,5 mg/kg PO q12h de meloxicam n’a pas permis de réduire significativement les indicateurs de douleur mesurés comparativement à un groupe témoin recevant de la saline. Les pigeons ayant reçu 2 mg/kg PO q12h de meloxicam ont montré une réduction significative des indicateurs de douleur mesurés par les différentes méthodes. Nos résultats suggèrent que l’administration de 2 mg/kg PO q12h aux pigeons suite à une chirurgie orthopédique procure une analgésie supérieure aux doses actuellement recommandées dans la littérature. / Pain assessment is especially difficult in avian species, since many birds behave as prey and do not show any external signs of distress. Choice of drugs and dosages used in clinical practice are most of the time based on extrapolation from other species and clinical experience. Few pharmacokinetic, efficacy or toxicity research studies are available in the literature. Most of these studies used noxious stimuli, such as electric or thermal stimuli, and results are therefore difficult to extrapolate to clinical pain. The objective of our project was to study the analgesic efficacy of two dosages of meloxicam in pigeons, using a femoral fracture pain model. Postoperative pain was assessed during the first four postoperative days by three different methods: weight bearing load on the fractured limb versus the controlateral limb, four different descriptive pain scales and ethogram realization based on video recordings. Administration of 0.5 mg/kg PO q12h of meloxicam did not show any reduction in the measured level of pain compared to the control group that received saline. However, pigeons that received 2 mg/kg PO q12h showed a significant decrease in their pain levels, with the three different pain assessment methods. Our results suggest that 2 mg/kg can provide a superior level of analgesia compared to the dosages recommended in the current literature, for pigeons that have undergone an orthopedic surgery.

This thesis focuses on conflict resolution and collective decision-making in co-navigating pigeons, Columba livia. These birds have a remarkable homing ability and frequently fly in flocks. Group navigation demands that group members reach consensus on which path to follow, but the mechanisms by which they do so remain largely unexplored. Pigeons are particularly suitable for studying these mechanisms, due to their sociality and the fact that their possession of information can easily be altered and quantified. I present the results of a series of experiments that manipulated the experience of homing pigeons in various ways so as to observe the effect of information they had previously gathered on their group behaviour. Key findings were: Previous navigational experience contributes to the establishment of leader-follower relationships. The larger the difference in experience between two co-navigating pigeons, the higher the likelihood the more experienced bird will emerge as leader. Shared homing experience through repeated joint flights can allow two pigeons to develop into a “behavioural unit”. They form spatial sub-groups when flying with less familiar birds, and perform a similar transition between compromise- and leadership-dominated flights as single birds, although they are more likely to accept compromise routes. Such previous association histories between birds can thus affect collective decision-making in larger flocks. There is a trade-off between the amount of spatial information handled and the efficiency with which such information can be applied during homing. Leading/following behaviour is influenced by the recency of the route memories. Leadership hierarchies in pigeon flocks appear resistant to changes in the navigational knowledge of a subset of their members, at least when these changes are relatively small in magnitude. The stability of the hierarchical structure might be beneficial during decision-making. Mathematical modelling suggests that underlying hierarchical social structures can increase navigational accuracy. Hierarchically organised groups with the smallest number of strong connections achieve highest accuracy. Group leader-follower dynamics resemble the underlying social structure.

Individuals experience risk ubiquitously, but measuring risk taking is difficult. The balloon analogue risk task (BART) was developed in order to assess risk taking through having subjects press a key that accrues reward but also risk losing all reward with each press. In humans, greater responding in this task is associated with other maladaptive risk taking behaviors. The present research modeled this relationship in pigeons due to their previously shown propensity towards risk taking behavior. Experiment 1 used an unsignaled balloon task in which losing could only occur after 5 pecks. Results showed below optimal performance with greater pecks associated with faster acquisition of risk taking in the suboptimal choice task and evidence of modulation by delay discounting measures. Experiment 2 signaled the number of pecks with colors and tested multiple hoppers as a reinforcement modality to increase performance. Results showed only signaling the number of pecks improved performance and was related to performance in the high risk BART task. Both the low and high risk variants were associated with slower suboptimal choice acquisition and again had evidence of modulation by delay discounting measures. Potential shared underlying mechanisms are discussed.