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Baragli,P.; Cozzi,A; Rugani, R.; Sighieria, C.; Regolin, L. |
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Title |
Delayed search for non-social goals by Equids (Equus caballus and Equus asinus) |
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Conference Article |
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2008 |
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IESM 2008 |
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cognitive abilities, delayed-response, Equids, working memory. |
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Delayed-responses have been traditionally employed to investigate the temporal characteristics of animals“ ability to represent and recall objects that have disappeared. In the typical condition, the animal, usually a mammal, observes the experimenter hiding an interesting goal (e.g. some food) in a certain location. A delayed-response task (DRT) was administered to 4 female Esperia pony (2 years old) coming from a free-range breed (Frosinone, Italy) and to 7 female Amiata donkeys (4.2±2 years old) coming from a conservation stock (University of Pisa, Italy). The DRT's apparatus was located in a square fence. A single ”U-shaped“ screen (330x160x140 cm) made by wood shavings blocks was positioned in the centre of the fence. A gap (40x50 cm) on the ground was in the middle of the central side of the U-shaped-screen and served to make the food-attractor disappear. The food-attractor consisted in cereal flakes and fresh grass for ponies and cereal flakes for donkeys. A bucket full of food was placed on a dolly tied on a rope which could be pulled by an experimenter. In a preliminary training each animal was allowed to eat food from the bucket and, while the animal was eating, the dolly was gently pulled away from the animal, and beyond the screen through the gap. The subjects needed to move around of the screen in order to retrieve the food. As a reinforcement, they were allowed to eat some food from the bucket once behind the screen. From trial to trial, the bucket was presented farther and farther (starting with a distance of 1 m in front of the screen to reach 7 m). Therefore subjects were tested in the DRT requiring them to rejoin the bucket with the goal-food disappearing behind the screen as in the preliminary training but following a 10 s delay. For the DRT, the bucket was placed 7 m in front of the screen, 3 m away from the animal's starting area. Then the dolly was pulled away from the animal. Ten seconds after the disappearance of the dolly behind the screen the animal was released from the starting area. The DRT ended when the subject had reached the attractor behind the screen on 3 consecutive trials. Results showed that all animals were able to rejoin the food behind the screen after 10 s delay. The mean time of the delayed-response (mean±sd, in s) in the ponies (1st: 19.8±8; 2nd: 10.8±2.2; 3rd: 12.8±2.8) and in the donkeys (1st: 28.4±10; 2nd: 26.9±13; 3rd: 24.3±16.6) showed a trend to decrease from first trial to third. These preliminary results suggest that like other mammals our ponies and donkeys can maintain a working memory trace of the location where biologically attractive objects have been seen to disappear. In conclusion, this study paves the way to set up a viable model system for the investigation of the more sophisticated aspects of Equids” cognitive abilities such as working memory. |
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Department of Veterinary Anatomy, Biochemistry and Physiology, University of Pisa, Viale delle Piagge 2 – 56124, Pisa, Italy |
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Cozzi, A |
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IESM 2008 |
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Talk 15 min IESM 2008 |
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yes |
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Equine Behaviour @ team @ |
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4475 |
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Author |
Flauger, B. |
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Title |
The introduction of horses into new social groups with special regard to their stress level |
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2011 |
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Keywords |
Pferd; Equiden; Eingliederungstechnik; Integrationspferd; Stress; Cortisol; Endokrine Reaktion; Gruppenhaltung; Verletzungsgefahr; Aggression; Futterplatzwahl; Kot; Geruchssinn; Mensch-Pferd Interaktion; horse; equids; introduction technique; integration horse; stress; cortisol; endocrine response; group housing; injury risk; aggression; feeding decision; faecal sample; olfaction; human-horse interaction |
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Horses are a highly social species living in complex social systems which should require them to memorise and generalise social experiences and distinguish between familiar and unfamiliar conspecifics. In the main part of my thesis I concentrated on the specific conflict situation of a horse being introduced into a new social group, and investigated its behaviour and stress level. Horses were either introduced (1) immediately, (2) after an observation period, or (3) together with an integration horse after an observation period. Additionally, in the second part of my thesis I arranged several experiments to elaborate additional aspects which could affect the behaviour of horses during introductions. In this study I could describe a simplified method for measuring stress through the analysis of faecal GCMs in horses. An enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3?,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. The new assay increases the accuracy of the test and lowers the expenses per sample; also storing of samples at room temperature after collection is less critical. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports (chapter 1). Comparing the different introduction techniques, the introduction with an integration horse led to significantly less total interactions and lower levels of aggression than the introduction of single horses, both immediately and after several days of observing the new group. Additionally, by observing the behaviour of the horses during everyday sociality I could develop a formula describing the interrelationship between expected aggression level and enclosure size per horse. The curve takes an exponential shape. Starting from a space allowance of 300 m2 and more per horse, the amount of aggressions per hour approaches zero. For the reduction of aggression levels and injury risks in socially kept horses I recommend an enclosure size of at least 300 m2 per horse (chapter 2). I further investigated the stress level of the introduced animals. Horses which were immediately introduced did not show elevated faecal GCMs. In contrast, horses which were introduced after an observation period had slightly elevated values 2 and 3 days after the introduction. For horses introduced together with an integration horse faecal GCMs were significantly above the baseline value on the day of introduction and 1 day after it. These differences between introduction techniques indicate that the introduction event itself is not as stressful as previously assumed. Rather standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses (chapter 3). In the commentary of chapter 4 several studies are discussed which failed to demonstrate social learning in horses. It is argued that they did not consider important aspects which could have an influence, such as the dominance status or the social background of the horses (chapter 4). In chapter 5 a social feeding situation was investigated. The social rank as well as the position of conspecifics affected the feeding strategy of horses. Domestic horses used social cognition and strategic decision making in order to decide where to feed. When possible they tended to return to the same, continuously supplied feeding site and switched to an ?avoidance tendency? in the presence of dominant horses or when another horse was already feeding there (chapter 5). One possibility to recognize group members is through olfactory recognition. In chapter 6 it is shown that horses are able to distinguish their own from their conspecifics? faeces. In addition, they paid most attention to the faeces of those group members from which they received the highest amount of aggressive behaviour (chapter 6). Horses show cognitive abilities because they are able to use humans as local enhancement cues when searching for food, independently of their body posture or gaze consistency when the persons face them. Moreover, they seem to orientate on the attention of familiar persons more than of unfamiliar persons (chapter 7). Altogether, the results of this thesis provide further support for the view that horses show good conflict resolution strategies. They are perfectly able to deal with the conflict situation of being introduced to new group members, and the introduction event itself is not as stressful as previously assumed. It is rather suggested that standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses. All additional experimental set-ups could demonstrate that horses are well capable of social cognition. |
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Ph.D. thesis |
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Equine Behaviour @ team @ epub18463 |
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5736 |
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Author |
Burla, J.-B.; Siegwart, J.; Nawroth, C. |
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Title |
Human Demonstration Does Not Facilitate the Performance of Horses (Equus caballus) in a Spatial Problem-Solving Task |
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Journal Article |
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Year |
2018 |
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Animal |
Abbreviated Journal |
Animal |
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8 |
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6 |
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96 |
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Keywords |
detour task; equids; social cognition; social learning; spatial cognition |
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Horses’ ability to adapt to new environments and to acquire new information plays an important role in handling and training. Social learning in particular would be very adaptive for horses as it enables them to flexibly adjust to new environments. In the context of horse handling, social learning from humans has been rarely investigated but could help to facilitate management practices. We assessed the impact of human demonstration on the spatial problem-solving abilities of horses during a detour task. In this task, a bucket with a food reward was placed behind a double-detour barrier and 16 horses were allocated to two test groups of 8 horses each. One group received a human demonstration of how to solve the spatial task while the other group received no demonstration. We found that horses did not solve the detour task more often or faster with human demonstration. However, both test groups improved rapidly over trials. Our results suggest that horses prefer to use individual rather than social information when solving a spatial problem-solving task |
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Equine Behaviour @ team @ |
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6392 |
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Author |
h:, M.; Lévy, F.; Fortin, M.; Leterrier, C.; LansadLansade, L. |
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Title |
Stress and temperament affect working memory performance for disappearing food in horses, Equus caballus |
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Journal Article |
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Year |
2013 |
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Animal Behaviour |
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86 |
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6 |
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1233-1240 |
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delayed-response task emotion; equid; Equus caballus; fearfulness; individual difference; personality; stress; temperament |
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In the present study, we sought to determine the influence of stress and temperament on working memory for disappearing food in horses. After assessment of five dimensions of temperament, we tested working memory of horses using a delayed-response task requiring a choice between two food locations. Delays ranging from 0 to 20 s were tested. The duration of working memory for disappearing food was first characterized without stressors (N = 26). The horses were then divided into two groups and their performance was assessed under stressful (exposure to acute stressors prior to testing, N = 12) or control conditions (N = 12). Results showed that the duration of working memory for disappearing food lasted at least 20 s under nonstressful conditions, and that under stressful conditions this duration lasted less than 12 s. This stress-induced impairment confirms in a nonrodent species that working memory performance is very sensitive to exposure to stressors. In addition, working memory performance in horses is influenced by the temperamental dimension of fearfulness according to the state of stress: fearful horses showed better performance under control conditions and worse performance under stressful conditions than nonfearful horses. These findings are discussed in the context of the Yerkes–Dodson law of stress and performance. |
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0003-3472 |
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Equine Behaviour @ team @ |
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5746 |
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[No authors listed] |
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Title |
African horse sickness--a serious disease |
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2006 |
Publication |
Australian Veterinary Journal |
Abbreviated Journal |
Aust Vet J |
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Volume |
84 |
Issue |
5 |
Pages |
N24-5 |
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Keywords |
*African Horse Sickness/epidemiology/pathology/prevention & control/transmission; African horse sickness virus/pathogenicity; Animals; Australia/epidemiology; Disease Outbreaks/prevention & control/veterinary; *Equidae; Horses; Vaccination/veterinary |
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0005-0423 |
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PMID:16739521 |
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Equine Behaviour @ team @ |
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2356 |
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Blunden, A.S.; Smith, K.C.; Whitwell, K.E.; Dunn, K.A. |
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Systemic infection by equid herpesvirus-1 in a Grevy's zebra stallion (Equus grevyi) with particular reference to genital pathology |
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Journal Article |
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1998 |
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Journal of Comparative Pathology |
Abbreviated Journal |
J Comp Pathol |
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119 |
Issue |
4 |
Pages |
485-493 |
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Animals; Animals, Zoo; Epididymis/pathology/virology; Equidae/*virology; Herpesviridae Infections/diagnosis/pathology/*veterinary; Herpesvirus 1, Equid/isolation & purification/*pathogenicity; Lymph Nodes/pathology/virology; Male; Nasal Mucosa/pathology/virology; Pulmonary Edema/pathology; Spleen/virology; Testis/*pathology/virology |
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A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto undescribed aspects of the pathogenesis of naturally occurring EHV-1 infection in the male equine genital tract. Restriction digests of the isolate demonstrated a pattern similar to that of EHV-1 isolates previously recovered from aborted zebra and onager fetuses. |
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Animal Health Trust Centre for Preventive Medicine, Newmarket, Suffolk, UK |
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0021-9975 |
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PMID:9839210 |
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no |
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Equine Behaviour @ team @ |
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2239 |
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Author |
Dierenfeld, E.S. |
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Vitamin E in exotics: effects, evaluation and ecology |
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Journal Article |
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Year |
1994 |
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The Journal of Nutrition |
Abbreviated Journal |
J Nutr |
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124 |
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12 Suppl |
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2579s-2581s |
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Animal Feed/*analysis; Animals; Animals, Zoo/blood/*metabolism; Antelopes/blood/metabolism; Birds/blood/metabolism; Deer/blood/metabolism; Elephants/blood/metabolism; Equidae/blood/metabolism; Perissodactyla/blood/metabolism; Vitamin E/*administration & dosage/analysis/blood; Vitamin E Deficiency/pathology/physiopathology/veterinary |
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The pathophysiology and lesions associated with vitamin E deficiency are similar between domestic and exotic species, and circulating plasma concentrations are also similar between comparable groups. However, many ecological variables must be considered for the most relevant comparisons. Tissue values of vitamin E, apart from plasma, are unknown for most exotics. Dietary vitamin E requirements of exotic species and domestics appear to differ; based on natural foodstuff analyses and clinical observations, between 50 and 200 mg vitamin E/kg DM are necessary to prevent vitamin E deficiency, 5- to 10-fold higher than current livestock recommendations. |
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Department of Nutrition, Wildlife Health Center, Wildlife Conservation Society, Bronx, NY 10460 |
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0022-3166 |
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PMID:7996243 |
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no |
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Call Number |
Equine Behaviour @ team @ |
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2661 |
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Author |
Turner, J.W.J.; Liu, I.K.; Kirkpatrick, J.F. |
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Remotely delivered immunocontraception in free-roaming feral burros (Equus asinus) |
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Journal Article |
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Year |
1996 |
Publication |
Journal of reproduction and fertility |
Abbreviated Journal |
J Reprod Fertil |
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107 |
Issue |
1 |
Pages |
31-35 |
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Animals; *Animals, Wild; Contraception, Immunologic/methods/*veterinary; *Equidae; Feces/chemistry; Female; Pregnancy; Pregnancy Tests; Swine; Zona Pellucida/immunology |
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Regulation of local overpopulations of free-roaming feral equids is in demand worldwide for ecological balance and habitat preservation. Contraceptive vaccines have proven effective in feral horses, which breed seasonally, but no data are available for equids such as the burro, which is reproductively active all year round. In the present study, 27 individually identified female feral burros (Equus asinus) roaming free in Virgin Islands National Park (St John, US Virgin Islands; Lesser Antilles) were remotely treated with pig zonae pellucidae (PZP) vaccine. Between January and May, 16 burros were darted with a 1 ml emulsion of PZP plus Freund's adjuvant. Ten to twelve months later each treated burro was given a single booster injection of PZP plus adjuvant to maintain contraception through a second year. Eleven adult untreated jennies served as controls. Beginning one year after initial vaccination, these burros were monitored for pregnancy and foal production. Collection of data to determine treatment effect was not begun until 12 months after initial treatment to ensure that pregnancies existing before vaccination were not included. Pregnancy was assessed using previously validated methods for steroid metabolite measurement in fresh faecal samples. None of the PZP-treated burros produced foals between 0 and 12 months after the last inoculation. One PZP-treated burro tested positive for pregnancy at 10 months after the final inoculation. During this same period, six of 11 untreated burros tested pregnancy-positive, and four were observed with foals. There was no difference in pregnancy rates among treated, control and randomly sampled jennies between 12 and 24 months after the last inoculation. The results demonstrate that, in free-roaming feral burros that are reproductively active all year round: (1) burros can be accessed for remotely delivered PZP vaccination; (2) PZP contraception is effective; (3) PZP contraception is reversible; and (4) pregnancy can be reliably detected by faecal steroid analysis. |
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Department of Physiology and Molecular Medicine, Medical College of Ohio, Toledo 43699, USA |
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0022-4251 |
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PMID:8699431 |
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refbase @ user @ |
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144 |
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Kiltie, R.A.; Fan, J.; Laine, A.F. |
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Title |
A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology |
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Journal Article |
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Year |
1995 |
Publication |
Mathematical Biosciences |
Abbreviated Journal |
Math Biosci |
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126 |
Issue |
1 |
Pages |
21-39 |
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Animals; Carnivora; *Ecology; Equidae; *Evolution; Humans; Mathematics; Models, Biological; Moths; *Pattern Recognition, Visual; Pigmentation |
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Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs. |
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Department of Zoology, University of Florida, Gainesville |
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0025-5564 |
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PMID:7696817 |
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no |
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Call Number |
Equine Behaviour @ team @ |
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2660 |
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Author |
Sundaresan, S.R.; Fischhoff, I.R.; Dushoff, J.; Rubenstein, D.I. |
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Title |
Network metrics reveal differences in social organization between two fission-fusion species, Grevy's zebra and onager |
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Journal Article |
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Year |
2007 |
Publication |
Oecologia |
Abbreviated Journal |
Oecologia |
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Volume |
151 |
Issue |
1 |
Pages |
140-149 |
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Keywords |
Analysis of Variance; Animals; Behavior, Animal/*physiology; *Environment; Equidae/*physiology; Female; India; Kenya; Male; *Models, Theoretical; *Social Behavior; *Social Environment |
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Abstract |
For species in which group membership frequently changes, it has been a challenge to characterize variation in individual interactions and social structure. Quantifying this variation is necessary to test hypotheses about ecological determinants of social patterns and to make predictions about how group dynamics affect the development of cooperative relationships and transmission processes. Network models have recently become popular for analyzing individual contacts within a population context. We use network metrics to compare populations of Grevy's zebra (Equus grevyi) and onagers (Equus hemionus khur). These closely related equids, previously described as having the same social system, inhabit environments differing in the distribution of food, water, and predators. Grevy's zebra and onagers are one example of many sets of coarsely similar fission-fusion species and populations, observed elsewhere in other ungulates, primates, and cetaceans. Our analysis of the population association networks reveals contrasts consistent with their distinctive environments. Grevy's zebra individuals are more selective in their association choices. Grevy's zebra form stable cliques, while onager associations are more fluid. We find evidence that females associate assortatively by reproductive state in Grevy's zebra but not in onagers. The current approach demonstrates the utility of network metrics for identifying fine-grained variation among individuals and populations in association patterns. From our analysis, we can make testable predictions about behavioral mechanisms underlying social structure and its effects on transmission processes. |
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Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA. ssundare@princeton.edu |
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English |
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0029-8549 |
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PMID:16964497 |
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1863 |
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