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Author |
Pelé, M.; Sueur, C. |
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Title |
Decision-making theories: linking the disparate research areas of individual and collective cognition |
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Journal Article |
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Year |
2013 |
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Abbreviated Journal |
Animal Cognition |
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Volume |
16 |
Issue |
4 |
Pages |
543-556 |
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Optimality; Primates; Insects; Diffusion Model; Delay; Risk; Speed-accuracy; Trade-off |
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Abstract |
In order to maximize their fitness, animals have to deal with different environmental and social factors that affect their everyday life. Although the way an animal behaves might enhance its fitness or survival in regard to one factor, it could compromise them regarding another. In the domain of decision sciences, research concerning decision making focuses on performances at the individual level but also at the collective one. However, between individual and collective decision making, different terms are used resulting in little or no connection between both research areas. In this paper, we reviewed how different branches of decision sciences study the same concept, mainly called speed-accuracy trade-off, and how the different results are on the same track in terms of showing the optimality of decisions. Whatever the level, individual or collective, each decision might be defined with three parameters: time or delay to decide, risk and accuracy. We strongly believe that more progress would be possible in this domain of research if these different branches were better linked, with an exchange of their results and theories. A growing amount of literature describes economics in humans and eco-ethology in birds making compromises between starvation, predation and reproduction. Numerous studies have been carried out on social cognition in primates but also birds and carnivores, and other publications describe market or reciprocal exchanges of commodities. We therefore hope that this paper will lead these different areas to a common decision science. |
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Springer-Verlag |
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Equine Behaviour @ team @ |
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5692 |
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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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Manuscript |
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Year |
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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Abstract |
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 |
Komar, N. |
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Title |
West Nile virus: epidemiology and ecology in North America |
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Journal Article |
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Year |
2003 |
Publication |
Advances in Virus Research |
Abbreviated Journal |
Adv Virus Res |
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Volume |
61 |
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Pages |
185-234 |
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Keywords |
Animals; Bird Diseases/virology; Birds/virology; Culex/virology; Disease Reservoirs; Ecosystem; Epidemiology, Molecular; Horse Diseases/virology; Horses/virology; Humans; Insect Vectors; North America/epidemiology; Risk Factors; West Nile Fever/*epidemiology/transmission/veterinary; West Nile virus/genetics |
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Centers for Disease Control and Prevention, Division of Vector-Borne Infectious Diseases, Fort Collins, Colorado 80522, USA |
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0065-3527 |
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PMID:14714433 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2638 |
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Author |
Romano, N.; Vitale, F.; Alesi, D.R.; Bonura, F.; La Licata, R.; Intonazzo, V.; Dardanoni, G.; Mammina, C. |
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Title |
The changing pattern of human immunodeficiency virus type 1 infection in intravenous drug users. Results of a six-year seroprevalence study in Palermo, Italy |
Type |
Journal Article |
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Year |
1992 |
Publication |
American Journal of Epidemiology |
Abbreviated Journal |
Am J Epidemiol |
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Volume |
135 |
Issue |
11 |
Pages |
1189-1196 |
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Keywords |
Acquired Immunodeficiency Syndrome/*epidemiology; Adolescent; Adult; Chi-Square Distribution; Cross-Sectional Studies; Female; HIV Antibodies/blood; HIV Infections/*epidemiology; HIV Seroprevalence/*trends; *Hiv-1; Hepatitis B Antibodies/blood; Hepatitis B Surface Antigens/blood; Heroin; Humans; Incidence; Italy/epidemiology; Logistic Models; Male; Multivariate Analysis; Odds Ratio; Prevalence; Risk Factors; Substance Abuse, Intravenous/*epidemiology; Time Factors |
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Abstract |
A cross-sectional seroepidemiologic study was carried out between 1985 and 1990 in 1,567 heterosexual intravenous drug users who had been seen at the AIDS Regional Reference Center in Palermo, Italy, to evaluate the rate of human immunodeficiency virus type 1 (HIV-1) seroprevalence in this group and its long-term trend. Sixty serum samples collected from drug users in 1980 and 1983, before the founding of the Center (1985), were tested as well. Some demographic and behavioral risk factors were studied in a subgroup of intravenous drug users enrolled in 1985, 1987, and 1990 for their possible association with HIV-1. These factors were also studied in relation to hepatitis B virus infection, since both viruses share the same modes of spread. These drug users had a higher prevalence of markers for hepatitis B virus than of HIV-1 antibodies, and the prevalence rates in sera collected declined over time for both infections. The presence of both antibodies to HIV-1 and markers for hepatitis B virus was independently associated with the age of the drug user, the duration of drug use, and the year of serum collection. Antibodies to HIV-1 were observed more frequently in females than in males. No relation was found between education or employment status and the presence of HIV-1 antibodies or hepatitis B virus markers. Although new HIV-1 infections still occur, the decline in seroprevalence observed at the end of the 1980s might be related to modifications in social behavior among newer drug users, partial exhaustion of the susceptible population, and increasing risk awareness in more experienced users. |
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Giuseppe D'Alessandro Department of Hygiene and Microbiology, School of Medicine, University of Palermo, Italy |
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English |
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ISSN |
0002-9262 |
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Notes |
PMID:1626537 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
5258 |
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Author |
Baker, K.C.; Seres, E.; Aureli, F.; De Waal, F.B. |
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Title |
Injury risks among chimpanzees in three housing conditions |
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Journal Article |
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Year |
2000 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
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Volume |
51 |
Issue |
3 |
Pages |
161-175 |
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Keywords |
Aggression; *Animal Welfare; Animals; Female; *Housing, Animal; Male; *Pan troglodytes; Risk Assessment; Wounds and Injuries/*veterinary |
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Abstract |
Meeting the psychological needs of chimpanzees (Pan troglodytes) can be a challenge given their aggressiveness on the one hand and the complexity of their social lives on the other. It is unclear how to balance the need to provide opportunities for species-appropriate behavior against potential risks of injury chimpanzees may inflict on each other. This study evaluates the suggestion that simpler social environments protect chimpanzees from wounding. Over a two-year period all visible injuries to 46 adult males, 64 adult females, and 25 immature chimpanzees were recorded at the Yerkes Regional Primate Research Center. Approximately half of the subjects were mother-reared, and the rest were nursery-reared. Housing included compounds containing about 20 chimpanzees, interconnected indoor-outdoor runs for groups of up to 12 individuals, and smaller indoor-outdoor runs for pairs and trios. Annual wounding rates were calculated for serious wounds (extensive injuries and all those requiring veterinary intervention) as well as for minor wounds. Compound-housed chimpanzees incurred the highest level of minor wounding, but serious wounding levels were not affected by housing condition. Even with a period of dominance instability and elevated levels of wounding in one compound, compound chimpanzees were not injured more than those in smaller social groups over the long term. Nursery-reared females in moderate-sized groups were wounded more than mother-reared females. Also, nursery-reared males and females were wounded less often when paired with mother-reared companions. Overall, this study indicates that maintaining chimpanzees in pairs and trios would not be an effective means for reducing injuries. The management of wounding in chimpanzee colonies is influenced more by the sex and rearing composition of a colony. |
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Living Links Center, Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA. kateb@rmy.emory.edu |
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0275-2565 |
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PMID:10902665 |
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Call Number |
refbase @ user @ |
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188 |
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Author |
Thompson, J.A.; Brown, S.E. 2nd; Riddle, W.T.; Seahorn, J.C.; Cohen, N.D. |
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Use of a Bayesian risk-mapping technique to estimate spatial risks for mare reproductive loss syndrome in Kentucky |
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Journal Article |
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Year |
2005 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
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66 |
Issue |
1 |
Pages |
17-20 |
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Abortion, Veterinary/*epidemiology; Animals; Bayes Theorem; Female; Geography; Horse Diseases/*epidemiology; Horses; Kentucky/epidemiology; Models, Statistical; Pregnancy; Risk Factors |
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OBJECTIVE: To estimate spatial risks associated with mare reproductive loss syndrome (MRLS) during 2001 among horses in a specific study population and partition the herd effects into those attributable to herd location and those that were spatially random and likely attributable to herd management. Animals-Pregnant broodmares from 62 farms in 7 counties in central Kentucky. PROCEDURE: Veterinarians provided the 2001 abortion incidence proportions for each farm included in the study. Farms were georeferenced and data were analyzed by use of a fully Bayesian risk-mapping technique. RESULTS: Large farm-to-farm variation in MRLS incidence proportions was identified. The farm-to-farm variation was largely attributed to spatial location rather than to spatially random herd effects. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that there are considerable data to support an ecologic cause and potential ecologic risk factors for MRLS. Veterinary practitioners with more detailed knowledge of the ecology in the 7 counties in Kentucky that were investigated may provide additional data that would assist in the deduction of the causal factor of MRLS via informal geographic information systems analyses and suggest factors for inclusion in further investigations. |
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Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4475, USA. USA |
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English |
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0002-9645 |
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PMID:15691030 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2630 |
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Author |
Atwill, E.R.; Mohammed, H.O.; Lopez, J.W. |
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Title |
Evaluation of travel and use as a risk factor for seropositivity to Ehrlichia risticii in horses of New York state |
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Journal Article |
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Year |
1996 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
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Volume |
57 |
Issue |
3 |
Pages |
272-277 |
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Keywords |
Animals; Cross-Sectional Studies; Ehrlichiosis/epidemiology/*veterinary; Female; *Horse Diseases; Horses; Male; New York/epidemiology; Probability; Random Allocation; Risk Factors; *Travel |
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Abstract |
OBJECTIVES--To determine whether mean annual frequency and destination of equine travel was associated with exposure to Ehrlichia risticii and whether these associations were modified by horses' place of residence. DESIGN--Cross-sectional study. SAMPLE POPULATION--511 equine operations containing 2,587 horses were visited in New York state from a target population of 39,000 operations. PROCEDURE--Each horse was tested for serum antibodies against E risticii, using indirect fluorescent antibody. Information on the horse's travel history, farm's management practices, and surrounding ecology was obtained by personal interview and resource maps. Statistical analyses were performed on 2 cohorts of animals: all horses enrolled in the study and horses born on the property or that resided at least 4 years on the farm. Three county-based risk regions (RR) were identified by use of cluster analysis. RESULTS--Mean seroprevalence for each of the 3 RR was 2.4 (low risk), 8.5 (moderate risk), and 18.5% (high risk) for cohort 1 and 2.5, 8.0, and 18.4% for cohort 2. Among cohorts 1 and 2, pleasure riding and breeding trips were associated with exposure to E risticii, but horse residence (low, moderate, or high RR) was an effect modifier for these associations. Among cohort 1 and stratifying the analysis according to the RR for the travel destination, trail riding at low RR and trail riding at high RR were associated with exposure. Among cohort 2 and stratifying the analysis according to the RR for the travel destination, breeding trips were associated with exposure, and strong effect modification was present for horse residence (low, moderate, or high RR). CONCLUSIONS--Only certain types of travel to specific RR were associated with higher risk of exposure to E risticii. In many instances, travel was not associated, or was associated, with a reduced risk of exposure. |
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Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA |
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0002-9645 |
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PMID:8669754 |
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no |
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Equine Behaviour @ team @ |
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2658 |
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Author |
Palleroni, A.; Hauser, M.; Marler, P. |
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Title |
Do responses of galliform birds vary adaptively with predator size? |
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Journal Article |
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Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
8 |
Issue |
3 |
Pages |
200-210 |
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Keywords |
Adaptation, Psychological; Animals; *Avoidance Learning; *Behavior, Animal; Body Size; Chickens; Female; Food Chain; Male; *Pattern Recognition, Visual; *Predatory Behavior; *Recognition (Psychology); Risk Assessment |
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Past studies of galliform anti-predator behavior show that they discriminate between aerial and ground predators, producing distinctive, functionally referential vocalizations to each class. Within the category of aerial predators, however, studies using overhead models, video images and observations of natural encounters with birds of prey report little evidence that galliforms discriminate between different raptor species. This pattern suggests that the aerial alarm response may be triggered by general features of objects moving in the air. To test whether these birds are also sensitive to more detailed differences between raptor species, adult chickens with young were presented with variously sized trained raptors (small, intermediate, large) under controlled conditions. In response to the small hawk, there was a decline in anti-predator aggression and in aerial alarm calling as the young grew older and less vulnerable to attack by a hawk of this size. During the same developmental period, responses to the largest hawk, which posed the smallest threat to the young at all stages, did not change; there were intermediate changes at this time in response to the middle-sized hawk. Thus the anti-predator behavior of the adult birds varied in an adaptive fashion, changing as a function of both chick age and risk. We discuss these results in light of current issues concerning the cognitive mechanisms underlying alarm calling behavior in animals. |
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Primate Cognitive Neuroscience Laboratory, Department of Psychology, Harvard University, 33 Kirkland St., Cambridge, MA, 02138, USA. aliparti@wjh.harvard.edu |
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1435-9448 |
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PMID:15660209 |
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no |
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Equine Behaviour @ team @ |
Serial |
2496 |
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Author |
Jackson, R.R.; Pollard, S.D.; Li, D.; Fijn, N. |
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Title |
Interpopulation variation in the risk-related decisions of Portia labiata, an araneophagic jumping spider (Araneae, Salticidae), during predatory sequences with spitting spiders |
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Journal Article |
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Year |
2002 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
5 |
Issue |
4 |
Pages |
215-223 |
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Keywords |
Animals; Female; Male; Mental Processes; *Predatory Behavior; Risk Factors; *Spiders |
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Abstract |
The extent to which decision-making processes are constrained in animals with small brains is poorly understood. Arthropods have brains much smaller and simpler than those of birds and mammals. This raises questions concerning limitations on how intricate the decision-making processes might be in arthropods. At Los Banos in the Philippines, Scytodes pallidus is a spitting spider that specialises in preying on jumping spiders, and Portia labiata is a jumping spider that preys on S. pallidus. Scytodid spit comes from the mouth, and egg-carrying females are less dangerous than eggless scytodids because the female uses her chelicerae to hold her eggs. Held eggs block her mouth, and she has to release them before she can spit. The Los Banos P. labiata sometimes adjusts its tactics depending on whether the scytodid encountered is carrying eggs or not. When pursuing eggless scytodids, the Los Banos P. labiata usually takes detour routes that enable it to close in from behind (away from the scytodid's line of fire). However, when pursuing egg-carrying scytodids, the Los Banos P. labiata sometimes takes faster direct routes to reach these safer prey. The Los Banos P. labiata apparently makes risk-related adjustments specific to whether scytodids are carrying eggs, but P. labiata from Sagada in the Philippines (allopatric to Scytodes) fails to make comparable risk-related adjustments. |
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Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand |
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1435-9448 |
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PMID:12461599 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2591 |
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Author |
Fleurance, G.; Duncan, P.; Fritz, H.; Cabaret, J.; Cortet, J.; Gordon, I.J. |
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Title |
Selection of feeding sites by horses at pasture: Testing the anti-parasite theory |
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Journal Article |
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2007 |
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Applied Animal Behaviour Science |
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Appl. Anim. Behav. Sci. |
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108 |
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3-4 |
Pages |
228-301 |
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Keywords |
Foraging strategies; Horses; Parasite risk; Patch choice |
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Abstract |
Management of grazed grasslands for production and/or conservation objectives requires a thorough understanding of the choices of feeding sites by herbivores, and of the biological processes involved. Most models of the feeding strategies of herbivores are based on the principle that optimising the intake of energy (or some nutrient) is the primary goal of foragers but other selective forces, such as parasitism, could be important. Gastrointestinal parasites (including cyathostome nematodes) have powerful effects on the fitness of herbivores and may act as a major selection pressure favouring host behaviour that reduces the risk of encountering parasites. Among large herbivores, horses have perhaps the most marked tendency to select particular feeding sites within grasslands. We test here: (1) whether horses select feeding patches with relatively low parasite densities and (2) if their choice is affected by their parasite load. We used 10 two-year old saddle-horses and three periods. In the first period, the horses were under natural parasitism which varied strongly among individuals; in the second period they were all dewormed, and in the third, a sub-set of the horses was experimentally infected with cyathostome larvae. Ninety-eight percent of the infective larvae in the pasture were found <1 m from faeces. The main determinant of the choice of feeding patch by horses was the availability of patches of different parasite risk and grass height. Controlling for availability, the horses used tall grasses (>16 cm) less than expected, whether the grass was contaminated or not, and they selected for short patches >1 m from faeces, where the risk of encountering parasites was low. These results suggest that selection of feeding sites by horses is driven by an interaction between their nutritional and anti-parasite strategies: the horses avoid the patches of tall grass which are generally of low quality and areas contaminated by parasite larvae which leads them to prefer the patches of short grass far from faeces. The parasite status of the horses at the time of the experiment had no effect on their feeding choices. However, before concluding that the challenge by cyathostomes has no effect on the selection of feeding sites in horses, it will be necessary to test whether the history of parasitism of the individuals, rather than the current status, is important. |
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no |
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Equine Behaviour @ team @ |
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4228 |
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