Change search
Refine search result
123456 51 - 100 of 281
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 51.
    Elebring, Viktoria
    Linköping University, Department of Physics, Chemistry and Biology.
    Vad skiljer domesticerade värphöns från de röda djungelhönsen (Gallus gallus) i återhämtningsprocessen efter en standardiserad stressupplevelse?: En studie med ett didaktiskt perspektiv2011Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Tidigare studier har visat att domesticerade höns påvisar en lägre nivå av rädsla jämfört med förfadern, de röda djungelhönsen. I denna studie testades 18 domesticerade White Leghorn (WL) och 18 röda djungelhöns (RJF). Målet med studien var att studera återhämtningen för de båda raserna vid en standardiserad stressupplevelse. Försöket gick ut på att hönsen vistades i enskilda burar och blev efter ett dygn utsatta av en akut stress. Därefter startades observationerna omedelbart för att se när hönsen återhämtade sig och återigen började visa naturliga beteenden. Utifrån alla hönsens resultat beräknades medelvärde och standardfel för varje ras och kön, som sedan jämfördes med variansanalys (repeated measures ANOVA). Beteenden som visade signifikanta resultat över tiden analyseras och visade i några fall tyda på en återhämtningsprocess. Överlag visade White Leghorn på en snabbare och effektivare återhämtning jämfört med de röda djungelhönsen. Resultatet tyder även på att honor har en snabbare återhämtning jämfört med hanar. Studien innehåller även ett didaktiskt moment då etologi studerades utifrån skolverkets föreskrifter om vad biologiundervisning ska innehålla för grundskolans senare år. Läroplanen och kursplaner studerades därefter och jämfördes med läroböcker.

  • 52.
    Elmberg, Johan
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Dessborn, Lisa
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Arzel, Céline
    Andungar har bra koll när faran hotar2014In: Vår fågelvärld, ISSN 0042-2649, Vol. 73, no 3, p. 34-35Article in journal (Other (popular science, discussion, etc.))
  • 53.
    Elmberg, Johan
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Dessborn, Lisa
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Arzel, Céline
    Så undviker andungarna rovdjuren2015In: Svensk jakt, ISSN 0039-6583, Vol. 153, no 6, p. 38-40Article in journal (Other (popular science, discussion, etc.))
  • 54. Engkvist, R.
    et al.
    Malm, T.
    Svensson, A.
    Asplund, L.
    Isaeus, M.
    Kautsky, L.
    Greger, M.
    Lanberg, T.
    Makroalgsblomningar längs Ölands kuster, effekter på det lokala näringslivet och det marina ekosystemet. (English title: Macro algal blooms in the central Baltic proper, effects on the economy and the marine ecosystem.)2001Report (Refereed)
  • 55.
    Enquist, Magnus
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    Lind, Johan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Centre for the Study of Cultural Evolution. Brooklyn College, USA; Graduate Center of the City University of New York, USA.
    The power of associative learning and the ontogeny of optimal behaviour2016In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, no 11, article id 160734Article in journal (Refereed)
    Abstract [en]

    Behaving efficiently (optimally or near-optimally) is central to animals' adaptation to their environment. Much evolutionary biology assumes, implicitly or explicitly, that optimal behavioural strategies are genetically inherited, yet the behaviour of many animals depends crucially on learning. The question of how learning contributes to optimal behaviour is largely open. Here we propose an associative learning model that can learn optimal behaviour in a wide variety of ecologically relevant circumstances. The model learns through chaining, a term introduced by Skinner to indicate learning of behaviour sequences by linking together shorter sequences or single behaviours. Our model formalizes the concept of conditioned reinforcement (the learning process that underlies chaining) and is closely related to optimization algorithms from machine learning. Our analysis dispels the common belief that associative learning is too limited to produce ‘intelligent’ behaviour such as tool use, social learning, self-control or expectations of the future. Furthermore, the model readily accounts for both instinctual and learned aspects of behaviour, clarifying how genetic evolution and individual learning complement each other, and bridging a long-standing divide between ethology and psychology. We conclude that associative learning, supported by genetic predispositions and including the oft-neglected phenomenon of conditioned reinforcement, may suffice to explain the ontogeny of optimal behaviour in most, if not all, non-human animals. Our results establish associative learning as a more powerful optimizing mechanism than acknowledged by current opinion.

  • 56.
    Ericsson, Maria
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Stress in chickens: Effects of domestication and early experience on behaviour and welfare2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    I denna avhandling presenteras resultat från fyra studier där alla har effekter av stress hos höns som gemensam nämnare. Vi har främst tittat på hur stress tidigt i livet påverkar beteendet och mängden stresshormoner i blodet på kort och lång sikt, men även hur den tidiga stressen kan påverka avkomman. I två av studierna undersöks också effekterna av domesticering.

    Domesticeringen, processen där vi avlat djur på tamhet och andra önskvärda anlag, har anpassat djuren till våra mänskliga förhållanden. Förfadern till alla våra domesticerade raser, det Röda djungelhönset, finns fortfarande kvar i vida populationer i Sydostasien där de lever i skogar. Detta är en stor fördel då man vill studera domesticeringsprocessen och vilka förändringar som uppkommit, eftersom man kan göra studier mellan raser och sedan direkt jämföra skillnader och likheter. Domesticeringen av höns inleddes för ca 8000 år sedan. Man tror att högre tolerans mot stress kan vara en bidragande faktor i domesticeringsprocessen eftersom tamhönsen har fått anpassa sig till miljöer och förhållanden som egentligen är kan betraktas som onaturliga för en höna, till exempel mycket stora flockar, trånga utrymmen och inomhusvistelse.

    Ägg och kyckling är viktiga livsmedel i stora delar av världen och bara i Sverige kläcks många miljoner höns till kött- och äggproduktion varje år. På kläckerier utsätts kycklingar för en rad av potentiellt stressande situationer och behandlingar och man har varit osäker på om detta påverkar kycklingarna negativt. Forskning visar att stress tidigt i livet kan störa utvecklingen av bl.a. hjärnan och stressystemet, som kontrollerar utsöndringen av stresshormoner. Negativa erfarenheter tidigt i livet kan ge upphov till bl.a. beteendestörningar, sänkt immunförsvar och påverka kognitiva beteenden på senare i livet. Det innebär att det kan vara mer allvarligt att utsättas för stress när man är liten jämfört med när man är äldre. Vid stress ökar mängden stresshormoner i blodet. Detta leder till att beteendet förändras och vissa kroppsfunktioner minskar i aktivitet för att energin istället behövs i musklerna. Kroppen förbereder sig på att försvara sig mot det potentiella hotet genom kamp eller flykt. Genom att ta blodprov kan man mäta mängden stresshormoner.

    I ett projekt undersöktes välfärd hos nykläckta kycklingar och huruvida hanteringen på kläckerier kan bidra till fysiologiska och beteendemässiga förändringar hos djuren. Vidare har vi undersökt hur stressystemet utvecklas tidigt i livet, om det finns skillnader i hur Röda djungelhöns och domesticerade värphöns reagerar. Vi har också undersökt om stress vid olika åldrar under kycklingstadie och pubertet kan ge effekter i vuxen ålder och slutligen har vi undersökt hur akut stress hos vuxna djur påverkar beteende och en rad olika hormoner.

    Resultaten visar att kycklingstadiet och puberteten kan anses som stresskänsliga perioder och ge upphov till kort- och långsiktiga effekter på beteende, genexpression och stressfysiologi. Även avkomman kan i vissa avseenden påverkas. Vi har också kunnat bekräfta att kycklingar har en fullt fungerande stressrespons redan från dag ett efter kläckning. De potentiellt stressande upplevelserna på kläckerier har en påverkan på hur vissa gener kopplade till stress uttrycks i hjärnan. Hanar i vuxen ålder verkar påverkas mer av den tidiga hanteringen än vad honor gör. Vidare visar vi att domesticeringen har påverkat hur höns reagerar på stress både tidigt i livet och i vuxen ålder.

  • 57.
    Favati, Anna
    Stockholm University, Faculty of Science, Department of Zoology.
    Social dominance and personality in male fowl (Gallus gallus domesticus)2013Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Individuals in social species commonly form dominance relationships among each other, and

    are often observed to differ in behaviour depending on their social status. However, whether

    such behavioural differences are a consequence of dominance position, or also a cause to it,

    remains unclear. In this thesis I therefore investigated two perspectives of the relationship

    between social dominance and personality in the domestic fowl (Gallus gallus domesticus), a

    social species that forms relatively stable dominance hierarchies. In paper I I investigated the

    influence of social status on the expression and consistency of behaviours by experimentally

    changing status between repeated personality assays. The level of vigilance, activity and

    exploration changed with social status, while boldness and territorial crows appeared as

    stable individual properties, independent of status. These results showed that social status

    contribute to both variation and consistency in behavioural responses. Social status should

    therefore be taken into account when investigating and interpreting variation in personality.

    In paper II I showed that behaviour in a novel arena test and during encounter with an

    opponent can predict social status, more specifically that fast exploration and aggressiveness

    predicted a dominant social position. Together, these results highlight the dynamics of the

    two-way relationship between social position and individual behaviour and indicate that

    individual behaviour can both be a cause and a consequence of social status.

  • 58.
    Favati, Anna
    Stockholm University, Faculty of Science, Department of Zoology.
    The relationship between personality and social dominance in the domestic fowl – a critical perspective2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Social dominance relationships are formed within numerous animal species and reduce costly fights over resources. Dominant individuals often enjoy greater access to important resources such as food and mating partners, and are generally more aggressive, bold, active and explorative compared to subdominant individuals. These behavioural traits can differ among individuals, but they can also be consistent within the individual, thereby describing the individual’s personality type. However, the causal direction of the observed correlation between dominance and personality is not well studied. One possibility is that some personality types have higher chances of obtaining a dominant social position. This would suggest that personality has consequences for fitness. Another possible explanation is that possessing different social positions gives rise to consistent behavioural differences among individuals on various timescales. If social status has a lasting effect on behaviour, social status would constitute a ‘stable state’ that explains some of the diversity of personality types that has been observed in a multitude of animal species. Dominance and personality may also share underlying proximate factors. In this thesis, I investigate the relationship between social dominance and personality using male domestic fowl, Gallus gallus domesticus. The species is group-living with pronounced dominance hierarchies, and dominance increases male access to mating partners. I show that some aspects of personality, exploration, vigilance and in particular aggressiveness, increased a male’s chances of obtaining dominance (paper III, IV, V), and that aggressiveness can be even more important than body weight and ornament size (comb size, paper V) or recent experience of winning or losing (paper IV). Winning a social interaction resulted in an increase in aggressiveness, while a decrease was seen in males that experienced a loss (paper IV). By observing behaviour before and after changes in male dominance relationships, I further show that a recent (2 days earlier) change in social status induced behavioural adjustments to the new social status in activity, exploration and vigilance (paper I). By extending the time of the new social relationship to 3 weeks, I show that such behavioural changes did not continue (paper II). Finally, I show that the social environment during juvenile development had little impact on adult male competitiveness (paper V). Social interactions appear to have several short-term effects on behaviour, but did not contribute significantly to variation and long-term consistency of personality in male fowl. Instead, a male's personality, and in particular his aggressiveness, affected the outcome of dominance interactions. Overall, my studies reveal important consequences of individual differences in behaviour, and contribute to the highly sought-after empirical testing of hypotheses explaining variation in animal personality.

  • 59.
    Favati, Anna
    et al.
    Stockholm University, Sweden.
    Leimar, Olof
    Stockholm University, Sweden.
    Radesäter, Tommy
    Stockholm University, Sweden.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology. Stockholm University, Sweden.
    Social status and personality: stability in social state can promote consistency of behavioural responses2014In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 281, no 1774, p. 20132531-Article in journal (Refereed)
    Abstract [en]

    Stability of ‘state’ has been suggested as an underlying factor explainingbehavioural stability and animal personality (i.e. variation among, andconsistency within individuals in behavioural responses), but the possibilitythat stable social relationships represent such states remains unexplored.Here, we investigated the influence of social status on the expression andconsistency of behaviours by experimentally changing social status betweenrepeated personality assays. We used male domestic fowl (Gallus gallusdomesticus), a social species that forms relatively stable dominance hierarchies,and showed that behavioural responses were strongly affected bysocial status, but also by individual characteristics. The level of vigilance,activity and exploration changed with social status, whereas boldnessappeared as a stable individual property, independent of status. Furthermore,variation in vocalization predicted future social status, indicatingthat individual behaviours can both be a predictor and a consequence ofsocial status, depending on the aspect in focus. Our results illustrate thatsocial states contribute to both variation and stability in behaviouralresponses, and should therefore be taken into account when investigatingand interpreting variation in personality.

  • 60.
    Favati, Anna
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Løvlie, Hanne
    Leimar, Olof
    Stockholm University, Faculty of Science, Department of Zoology.
    Effects of social experience during development on competitive ability and personality traits in male domestic fowlManuscript (preprint) (Other academic)
    Abstract [en]

    The ability to dominate conspecifics and thereby gain access to important resources depends on a number of traits and skills that may be both heritable and influenced by the environment. Experience of dominance relationships during development is a potential source of learning such skills. We here study the relative importance of social experience, personality, and morphological traits on competitive ability in male domestic fowl (Gallus gallus domesticus). By letting males grow up as either a single (dominant) male, as the dominant male of a pair, or as an intermediate ranked male in a group of males, we investigate if competitiveness in social interactions (winning duels) is mainly due to individual qualities or also influenced by social experience. We found that males were consistent over time in their competitive ability. Single raised males were inferior to pair dominant males and group-raised males in competitive ability, while pair dominant and group males did not differ significantly. This indicates that social training is important for future fighting success, but that the social position during development does not have a decisive influence on male fighting success in adulthood. Aggression and comb size, the latter possibly being a proxy for testosterone levels, had a marked effect on competitive ability. Together, our results indicate that certain behavioural and morphological traits are more important than experience of a social position in shaping competitive ability. These findings elucidate the relationship between social dominance and personality.

  • 61.
    Favati, Anna
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Løvlie, Hanne
    Leimar, Olof
    Stockholm University, Faculty of Science, Department of Zoology.
    Individual aggression, but not winner–loser effects, predicts social rank in male domestic fowl2017In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 28, no 3, p. 874-882Article in journal (Refereed)
    Abstract [en]

    Many factors can affect the probability for an individual to obtain a high social rank, including size, weaponry, and behavioral attributes such as aggression. Recent experiences of winning or losing can also affect the chances of winning future contests, commonly referred to as “winner–loser effects”. Individuals often differ in behavior in a consistent way, including in aggression, thereby showing differences in personality. However, the relative importance of recent experience and aspects of personality in determining rank, as well as the extent to which winning or losing affects aggression, has rarely been studied. Here, we investigate these questions using male domestic fowl. We matched males for body size, comb size, and aggression in pair-wise duels to: 1) study the effect of contest outcome on aggression and 2) compare the effect of individual aggression and contest experience on future social status in small groups. We found that aggression was a highly repeatable personality trait and that aggression increased after winning and decreased after losing. Nevertheless, such winner–loser effects were not enough to increase the odds of becoming dominant in a small group. Instead, aggressiveness measured prior to a contest experience best predicted future rank. Boldness and exploration did not predict rank and of the 2, only boldness was positively correlated with aggressiveness. We conclude that for male domestic fowl in contests among phenotypically matched contestants, aggressiveness is more important for obtaining high rank than winner–loser effects, or other aspects of personality.

  • 62.
    Favati, Anna
    et al.
    Stockholm Univ, Sweden.
    Uden, Eva
    Stockholm Univ, Sweden.
    Leimar, Olof
    Stockholm Univ, Sweden.
    Lovlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Personality remains: no effect of 3-week social status experience on personality in male fowl2018In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 29, no 2, p. 312-320Article in journal (Refereed)
    Abstract [en]

    Behavioral responses of male fowl did not depend on social rank after 3 weeks in stable groups, but were consistent over time for an individual. Theory suggests that stable social states, for example, stable social hierarchies, may lead to consistent variation in behavior, that is, variation in personality. Our results suggest that variation in personality is not a consequence of variation in social status and that personality is more important than current social position in determining individual behavior in stable groups.Individuals often differ in behavior in a consistent way, that is, they show variation in personality. Understanding the processes explaining the emergence and maintenance of this variation is a current major topic in the field of animal behavioral research. Recent theoretical models predict that differences in various "states" can generate individual variation in behavior. Previous studies have mainly focused on endogenous states like metabolic rate or energy reserves, but theory also suggests that states based on social interactions could play important roles in shaping personality. We have earlier demonstrated short-term status-dependent variation in behavior in the domestic fowl (Gallus gallus domesticus), but whether such behavioral variation remains also after a longer period of time, is unknown. Therefore, we examine the influence of social status on variation in behavior, using experimental manipulation of social status in pairs of male domestic fowl. We scored males in 3 personality assays (novel arena test, novel object test, and aggression test) before and after 3 weeks in pairs as either dominant or subordinate. We observed individual consistency of behavior despite alteration of social status. We further found no support for social status acting as a state that generates variation in personality over the used time interval: social status had no significant effect on the change in behavioral responses between repeated personality tests. Our results suggest that personality is more important than current social situation for describing individual behavior in stable groups.

  • 63.
    Fischer, Ida
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Does Lifestyle Affect the Attachment between Dogs, Canis familiaris, and Their Owner?2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to investigate if the dog’s behaviour and the interactions between the dog and the owner   differ depending on lifestyle, breed or sex of the dog. For this we employed the Strange Situation Procedure, a test inspired from Mary Ainsworth´s study,   which investigated the attachment of human infants to their mothers. There were two breeds, Border collie and Shetland sheepdog and a total of 58 dogs that participated in this study. The two breeds were divided into two lifestyles, competition dogs and pet dogs. A PCA was used to find correlations between the behavioural variables and the factors were then analysed in a Mann Whitney U test to test the differences between breed, sex and lifestyle. In this study no differences in behaviour between the two lifestyles were shown. However, the results showed that there were some differences between the two breeds and between the two sexes in behavioural expressions. The differences between the breeds were quite expected because there are many different breeds today which are selected for various morphology and behavioural traits which could influence their behaviour. The difference in behaviour between the two sexes can be because of evolutionary heredity. Further studies on this subject should have bigger and more even sample size, longer separation time, a more balanced gender distribution of the owners and to also analyze the cortisol levels.

  • 64. Fleischer, Siegfried
    et al.
    Bauhn, Lovisa
    Fors, Patrik
    En kolsänka med syrebildning på köpet2014In: Kemivärlden Biotech med Kemisk Tidskrift, ISSN 1650-0725, no 4, p. 24-24Article in journal (Other academic)
  • 65.
    Foyer, Pernilla
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Department of Military Studies, Military-Technology Division, Swedish Defence University, Stockholm, Sweden.
    Svedberg, Anna-Maria
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Nilsson, Emma
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wilsson, Erik
    Swedish Armed Forces Dog Training Unit, Märsta, Sweden.
    Olsen Faresjö, Åshild
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Behavior and cortisol responses of dogs evaluated in a standardized temperament test for military working dogs2016In: Journal of Veterinary Behavior: Clinical Applications and Research, ISSN 1558-7878, E-ISSN 1878-7517, Vol. 11, p. 7-12Article in journal (Refereed)
    Abstract [en]

    Military and police working dogs are often exposed to stressful or threatening events, and an improper response, e.g., fear, may implicate both reduced working efficiency and welfare. Therefore, identifying individuals that display a favorable response to potentially threatening situations is of great interest. In the present study, we investigated behavior responses of 85 prospective military working dogs in 4 subtests in a standardized temperament test used to select working dogs for the Swedish Armed Forces. Our goal was to evaluate behavioral responses in specific subtests and cortisol responses of candidate dogs. After dogs were rated as approved or nonapproved based on the test leader’s assessment of the full test result, we independently analyzed video recordings of 4 subtests. In addition, for 37 dogs, we analyzed pretest and posttest salivary cortisol levels. Dogs which were approved by the test leader for further training scored higher in the video recordings on emotionality and, in particular, fear-related behavior during a subset of the test and had higher levels of cortisol both before and after the test, than nonapproved dogs. Although this may actually reflect the desired traits, it could also indicate a bias in the selection procedure, which may pose limitations on the attempts to recruit the most suitable working dogs.

  • 66.
    Foyer, Pernilla
    et al.
    Swedish Defence University, Department of Military Studies, Military-Technology Division. Linköpings universitet, Biologi.
    Svedberg, Anna-Maria
    Linköpings universitet, Biologi.
    Nilsson, Emma
    Linköpings universitet, Biologi.
    Wilsson, Erik
    Swedish Armed Forces Dog Training Unit, Märsta, Sweden.
    Olsen Faresjö, Åshild
    Linköpings universitet, Avdelningen för samhällsmedicin.
    Jensen, Per
    Linköpings universitet, Biologi.
    Behavior and cortisol responses of dogs evaluated in a standardized temperament test for military working dogs2016In: Journal of Veterinary Behavior: Clinical Applications and Research, ISSN 1558-7878, E-ISSN 1878-7517, Vol. 11, p. 7-12Article in journal (Refereed)
    Abstract [en]

    Military and police working dogs are often exposed to stressful or threatening events, and an improper response, e.g., fear, may implicate both reduced working efficiency and welfare. Therefore, identifying individuals that display a favorable response to potentially threatening situations is of great interest. In the present study, we investigated behavior responses of 85 prospective military working dogs in 4 subtests in a standardized temperament test used to select working dogs for the Swedish Armed Forces. Our goal was to evaluate behavioral responses in specific subtests and cortisol responses of candidate dogs. After dogs were rated as approved or nonapproved based on the test leader’s assessment of the full test result, we independently analyzed video recordings of 4 subtests. In addition, for 37 dogs, we analyzed pretest and posttest salivary cortisol levels. Dogs which were approved by the test leader for further training scored higher in the video recordings on emotionality and, in particular, fear-related behavior during a subset of the test and had higher levels of cortisol both before and after the test, than nonapproved dogs. Although this may actually reflect the desired traits, it could also indicate a bias in the selection procedure, which may pose limitations on the attempts to recruit the most suitable working dogs.

  • 67.
    Fransson, Emma
    et al.
    Stockholms universitet.
    Folkesson, Lisa
    Bergstrom, Malin
    Östberg, Viveca
    Lindfors, Petra
    EXPLORING SALIVARY CORTISOL AND RECURRENT PAIN IN MID-ADOLESCENTS LIVING IN TWO HOMES2014In: International Journal of Behavioral Medicine, ISSN 1070-5503, E-ISSN 1532-7558, Vol. 21, no 1Article in journal (Refereed)
  • 68. Fransson, Thord
    et al.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Stach, Robert
    Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Barboutis, Christos
    Extensive fuelling in great reed warblers following the trans-Sahara crossing in springManuscript (preprint) (Other academic)
    Abstract [en]

    Migratory birds wintering in Africa face the challenge of passing the Sahara desert with little opportunities to forage. During spring migration birds thus arrive in the Mediterranean area after crossing the desert with very low energy reserves. Since early arrival to the breeding grounds often is of importance to maximize reproductive success, finding stopover sites with good refuelling possibilities after the Saharan passage is of utmost importance. Here we report on extensive fuelling in the great reed warbler, Acrocephalus arundinaceus, on the south coast of Crete in spring, the first land that they encounter after crossing the Sahara desert and the Mediterranean Sea in this area. Birds were trapped with mist nets at a river mouth, individually ringed and information about body mass, wing length, muscle score and fat score were recorded. Due to an exceptional high recapture rate at the trapping site (45%), we were able to calculate minimum stopover time and fuel deposition rates in 25 individual great reed warblers during one spring season. The large proportion of trapped great reed warbler compared to other species and the large number of recaptures suggests that great reed warbler actively choose this area for stopover. The relatively long stopover period at the site, the high fuel deposition rate (1 g day-1) and the large body mass increase show that great reed warblers at this site regularly deposit a much larger fuel load than needed for one continued flight stage to the north. It was also shown that birds with lower body mass at first capture had a higher fuel deposition rate than birds with higher body mass. This indicates that individuals are able to adjust their food intake in relation to energy reserves.

  • 69.
    Franzén, Louise
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Manipulation of monoamines and effects on behavior in crickets.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 70.
    Frost, Morgan
    University of Skövde, School of Bioscience. Gillberg Neuropsychiatry Centre.
    Social Perception in Autism: An eye-tracking and pupillometric study2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Typically developing humans innately place subjective value on social informa- tion and orient attention to it. This can be shown through eye tracking and pupillometry, a method used to show attentional engagement. Social brain de- velopment and social preference is present from infancy, and is thought to rely on a carefully balanced network of neurotransmitters and neural connections. Autism Spectrum Disorder (ASD) presents altered neural systems which cause individuals to perceive and process social information di↵erently, but the neuro- physiology of this di↵erence remains unclear. Previous research shows atypical gaze patterns, hyperarousal, and lack of orienting to social stimuli in ASD. Since autism is highly comorbid and shares traits with other neurodevelopmental dis- orders, it is dicult to distinguish aspects of these social processing di↵erences. This study used a group of 35 neuropsychiatric patients to investigate how in- dividuals with autism process social and non-social scenes. Eye tracking and pupillometry measures were collected while participants observed images of nat- ural scenes with or without a person. Participants with autism did not show a pupillary response to social images and were slower to fixate on the face re- gion than the other participants. Additionally there were correlations between clinical measures of social functioning and the length of time it took to fixate to faces. The results highlight important distinctions of social processing in autism. This thesis proposes a new perspective of looking at the social deficits present in autism spectrum disorder. It suggests reframing the current discus- sion from two leading hypotheses to a unified approach and formally considering the limitations of di↵ering types of stimuli.

  • 71.
    Gamberale-Stille, Gabriella
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Johansen, Aleksandra I.
    Stockholm University, Faculty of Science, Department of Zoology.
    Tullberg, Birgitta S.
    Stockholm University, Faculty of Science, Department of Zoology.
    Change in protective coloration in the striated shieldbug Graphosoma lineatum (Heteroptera: Pentatomidae): predator avoidance and generalization among different  life stages2010In: Evolutionary Ecology, ISSN 0269-7653, E-ISSN 1573-8477, Vol. 24, no 2, p. 423-432Article in journal (Refereed)
    Abstract [en]

    There are two major forms of protective coloration, camouflage and warning coloration, which often entail different colour pattern characteristics. Some species change strategy between or within life stages and one such example is the striated shieldbug, Graphosoma lineatum. The larvae and the pale brownish-and-black striated pre-diapause adults are more cryptic in the late summer environment than is the red-and black striation that the adults change to after diapause in spring. Here we investigate if the more cryptic pre-diapause adult and larval coloration may affect the aposematic function of the coloration as compared to the red adult form. In a series of trials we presented fifth instar larvae, pale or red adults to shieldbug-naïve domestic chicks, Gallus gallus domesticus, to investigate the birds’ initial wariness, avoidance learning, and generalization between the three prey types. The naïve chicks found the red adults most aversive followed by pale adults, and they found the larvae the least aversive. The birds did not find the larvae unpalatable and did not learn to avoid them, while they learned to avoid the two adult forms and then to a similar degree. Birds generalized asymmetrically between life stages, positively from larvae to adults and negatively from adults to larvae. We conclude that the lower conspicuousness in the pale forms of G. lineatum may entail a reduced aposematic function, namely a reduced initial wariness in inexperienced birds. The maintenance of the colour polymorphism is discussed

  • 72.
    Ghirlanda, Stefano
    et al.
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Brooklyn College, USA; CUNY Graduate Center, USA.
    Lind, Johan
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    ‘Aesop's fable’ experiments demonstrate trial-and-error learning in birds, but no causal understanding2017In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 123, p. 239-247Article in journal (Refereed)
    Abstract [en]

    Experiments inspired by Aesop's fable The crow and the pitcher have been suggested to show that some birds (rooks, Corvus frugilegus, New Caledonian crows, Corvus moneduloides, and Eurasian jays, Garrulus glandarius) understand cause–effect relationships pertaining to water displacement. For example, the birds may prefer to drop stones in water rather than in sand in order to retrieve a floating food morsel, suggesting that they understand that only the level of water can be so raised. Here we re-evaluate the evidence for causal understanding in all published experiments (23 928 choices by 36 individuals). We first show that commonly employed statistical methods cannot disentangle the birds' initial performance on a task (which is taken as an indicator of causal understanding) from trial-and-error learning that may occur during the course of the experiment. We overcome this shortcoming with a new statistical analysis that quantifies initial performance and learning effects separately. We present robust evidence of trial-and-error learning in many tasks, and of an initial preference in a few. We also show that both seeming demonstrations of causal understanding and of lack of it can be understood based on established properties of instrumental learning. We conclude that Aesop's fable experiments have not yet produced evidence of causal understanding, and we suggest how the experimental designs can be modified to yield better tests of causal cognition.

  • 73.
    Granovskiy, Boris
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Modeling Collective Decision-Making in Animal Groups2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many animal groups benefit from making decisions collectively. For example, colonies of many ant species are able to select the best possible nest to move into without every ant needing to visit each available nest site. Similarly, honey bee colonies can focus their foraging resources on the best possible food sources in their environment by sharing information with each other. In the same way, groups of human individuals are often able to make better decisions together than each individual group member can on his or her own. This phenomenon is known as "collective intelligence", or "wisdom of crowds." What unites all these examples is the fact that there is no centralized organization dictating how animal groups make their decisions. Instead, these successful decisions emerge from interactions and information transfer between individual members of the group and between individuals and their environment. In this thesis, I apply mathematical modeling techniques in order to better understand how groups of social animals make important decisions in situations where no single individual has complete information. This thesis consists of five papers, in which I collaborate with biologists and sociologists to simulate the results of their experiments on group decision-making in animals. The goal of the modeling process is to better understand the underlying mechanisms of interaction that allow animal groups to make accurate decisions that are vital to their survival. Mathematical models also allow us to make predictions about collective decisions made by animal groups that have not yet been studied experimentally or that cannot be easily studied. The combination of mathematical modeling and experimentation gives us a better insight into the benefits and drawbacks of collective decision making, and into the variety of mechanisms that are responsible for collective intelligence in animals. The models that I use in the thesis include differential equation models, agent-based models, stochastic models, and spatially explicit models. The biological systems studied included foraging honey bee colonies, house-hunting ants, and humans answering trivia questions.

  • 74.
    Grassini, Simone
    et al.
    Department of Psychology, University of Turku, Finland.
    Railo, Henry
    Department of Psychology, University of Turku, Finland.
    Valli, Katja
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre. Department of Psychology, University of Turku, Finland.
    Revonsuo, Antti
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre. Department of Psychology, University of Turku, Finland.
    Koivisto, Mika
    Department of Psychology, University of Turku, Finland.
    Visual features and perceptual context modulate attention towards evolutionarily relevant threatening stimuli: Electrophysiological evidence2019In: Emotion, ISSN 1528-3542, E-ISSN 1931-1516, Vol. 19, no 2, p. 348-364Article in journal (Refereed)
    Abstract [en]

    The snake detection hypothesis claims that predatory pressure from snakes has shaped the primate visual system, but we still know very little about how the brain processes evolutionarily important visual cues, and which factors are crucial for quick detection of snakes. We investigated how visual features modulate the electrophysiological markers of early attentional processes. In Experiment 1, we compared snake, rope, gun, and bird images to isolate the effects due to curvilinearity of the stimuli. The results showed that both snake and rope images elicited enhanced P1 and N1 event-related potential components as well as early posterior negativity (EPN). In Experiment 2, we studied whether nonthreatening curvilinear images (i.e., ropes) still elicit the enhanced electrophysiological responses when snake images are not presented as stimuli, and therefore the context does not provoke top-down attention to curvilinear shapes. Rope images still evoked an enhanced EPN, suggesting that curvilinear shapes are preferably captured by attentional processes. However, this effect was smaller than in Experiment 1, in which snake images were present. Thus, our results hint to the possibility that the perceptual context may interact with processing of shape information, drawing attention to curvilinear shapes when the presence of snakes is expectable. Furthermore, we observed that spatial frequency of the visual stimuli modulated especially the early electrophysiological responses, and decreased the differences between stimulus categories in EPN without completely eliminating them. The findings suggest that low-level and high-level mechanisms interact to give an attentional priority to potentially threatening stimuli.

  • 75.
    Grozelier, Anna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Labrador and German shepherd breed differences in dog-human communication2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As our long-term companions, dogs’ communication with us is perhaps the most developed of all human- animal ones. This study was aimed to investigate breed differences of German Shepherds and Labradors in dog-human communication. This was obtained through two tests: a problem-solving task and a pointing test. These two tests target both directions of communication: how much dogs understand and respond to the pointing and how they communicate with humans when facing a problem. Additionally, hair cortisol was measured in the dogs and dog owners filled a behavioural questionnaire (C-BARQ). The main breed difference I found was that Labradors performed better in both tests. I also found that the latency of the dogs’ choices in the pointing test correlated with many factors, e.g. they chose quicker when: choosing correctly, when they had many physical contacts with the experimenter in the problem-solving task, when they were more intense, energetic dogs, when they had higher hair cortisol levels and when they had a confident body posture. This indicates that the latency of choice could depend on the confidence of the dog and on the trust in the experimenter as well as on energy level and focus ability. Overall, this study revealed a limited amount of breed differences, compared to a parallel study on Labrador types (hunting and show dogs), showing that intra-breed differences can be more important than inter-breed ones on a behavioural level. 

  • 76. Guevara-Fiore, P.
    et al.
    Svensson, P. Andreas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Endler, J.A.
    Sex as moderator of early life experiences: interaction between rearing environment and sexual experience in male guppies2012In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 84, no 4, p. 1023-1029Article in journal (Refereed)
    Abstract [en]

    The effects of learning have been neglected in studies of sexual selection because previous researchers have assumed, implicitly or explicitly, that sexual behaviour is genetically fixed. To understand the role of learning in sexual selection, it is important to investigate how early experience interacts with adult experience to determine the use of different mating strategies. We explored this interaction by comparing the sexual behaviour of male guppies, Poecilia reticulata, raised in different social environments before and after they gained sexual experience. Males raised with other males performed long courtship displays at first, but decreased their courtship after they had gained sexual experience. However, for males raised only with females, sexual experience did not modify courtship duration. Males raised exclusively with females exhibited high rates of forced copulation attempts in their first encounter with a female, but reduced this behaviour after sexual experience. In contrast, males raised with other males did not modify their forced copulations. Adult sexual experience appeared to mitigate the behavioural differences caused by variation in rearing environment. Sexual experience helps males to find an optimal balance between courtship displays and forced copulation attempts. We also show that more males exhibited male–male aggression after sexual experience if they had social interactions with other males early in life. This study highlights that courtship and other sexual strategies are not fixed, and that several potential sources of variation exist in the development of an animal's sexual behaviour. Importantly, juvenile and adult experiences can interact to shape sexual behaviour in males.

  • 77.
    Gustafsson, Jannie Frida Linn
    Linköping University, Department of Physics, Chemistry and Biology.
    Thermoregulatory behavior and habitat use of Liolaemus aparicioi at two different altitudes2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The thermoregulation of lizards depends highly on the environment they inhabit. Thermoregulation is crucial for physiological processes and affects therefore the life history of the lizard. High altitudes are characterized by a colder climate than on lower altitudes, and these environmental factors affects the thermoregulation of lizards. Lizards can however adapt to colder climates by adjusting their physiology and/or behavior. In this study two populations of Liolaemus aparicioi, an endemic lizard inhabiting the valleys close to La Paz, were observed at two different altitudes to investigate any differences in behavior or habitat use that could compensate for the high altitude. The behavioral displays associated to thermoregulation and the use of habitat were recorded in order to assess how they allocated their time and how they used the habitat available. The mean values of most parameters measured indicated that the population on the high altitude do compensate for the high altitude by behavior and habitat use.

  • 78.
    Gustafsson, Jennie Frida Linn
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Thermoregulating behavior and habitat use of Liolaemus aparicioi2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The thermoregulation of lizards depends highly on the environment they inhabit. Thermoregulation is crucial for physiological processes and affects therefore the life history of the lizard. High altitudes are characterized by a colder climate than on lower altitudes, and these environmental factors affects the thermoregulation of lizards. Lizards can however adapt to colder climates by adjusting their physiology and/or behavior. In this study two populations of Liolaemus aparicioi, an endemic lizard inhabiting the valleys close to La Paz, were observed at two different altitudes to investigate any differences in behavior or habitat use that could compensate for the high altitude. The behavioral displays associated to thermoregulation and the use of habitat were recorded in order to assess how they allocated their time and how they used the habitat available. The mean values of most parameters measured indicated that the population on the high altitude do compensate for the high altitude by behavior and habitat use.

  • 79.
    Gustavsson, Linda
    Linköping University, Department of Physics, Chemistry and Biology.
    Evaluation of varied enrichment schedules for two feline and one primate species at Parken Zoo2011Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    An evaluation of varied enrichment and feeding schedules were conducted on three spices, drill, Pallas’s cat and cheetah, at Parken Zoo in Sweden. Varied schedules of enrichment and feeding are used to prevent the animals from knowing when the administration of these events are going to happen since anticipation can lead to a number of negative changes in the behaviours of the animals. Scan sampling was used to gather behavioural data of the animals and the data was then used to answer a number of questions about the extent of success of the varied schedule: 1.Is the varied schedule experienced as unpredictable for the animals? 2. Are there any negative behaviours associated with the scheduled enrichments? 3. What are the reactions to the enrichment being withheld at certain days? The results showed that the animals did not perceive the scheduled events as predictable; pacing in cheetahs and aggressive behaviours in Pallas’s cats seemed to be directly associated with the events; active behaviours in the drills decreased and aggressiveness increased as an immediate result of withholding enrichment. Implications for the animals and the zoo in light of the results are discussed.

  • 80.
    Hagman, Mattias
    et al.
    University of New South Wales, Australia.
    Löwenborg, Kristin
    Stockholm University, Faculty of Science, Department of Zoology.
    Shine, Richard
    University of Sydney, Australia.
    Determinants of anti-predator tactics in hatchling grass snakes (Natrix natrix)2015In: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 113, p. 60-65Article in journal (Refereed)
    Abstract [en]

    Many organisms exhibit diverse anti-predator tactics, influenced by genetics and prior experience. In ectothermic taxa, offspring phenotypes are often sensitive to developmental temperatures. If the effectiveness of alternative anti-predator responses depends on thermally sensitive traits, then the temperatures experienced during embryonic life should also affect how offspring respond to an approaching predator. We incubated 16 clutches of Swedish grass snakes (Natrix natrix) at a range of developmental temperatures, and scored body size, colour pattern, locomotor performance and anti-predator responses of 213 hatchlings from those clutches. A hatchling snake’s size and locomotor abilities were affected by its clutch of origin, its developmental temperature, and by an interaction between these two factors. Anti-predator tactics were strongly linked to locomotor ability, such that slower snakes tended to rely upon aggressive displays rather than flight. Incubation temperatures that generated slow (and thus aggressive) snakes also modified the colour of the snake’s nuchal spot. Temperatures in the low to medium range generated mostly cream, white and orange spots, whereas medium to high temperatures generated more yellow spots. Incubation effects, and gene X environment interactions, thus may generate complex correlations between morphology, locomotor ability, and anti-predator tactics.

  • 81.
    Hagman, Mattias
    et al.
    Univ Sydney, Sch Biol Sci A08, Sydney, NSW 2006, Australia.
    Shine, Rick
    Univ Sydney, Sch Biol Sci A08, Sydney, NSW 2006, Australia.
    Australian tadpoles do not avoid chemical cues from invasive cane toads (Bufo marinus)2008In: Wildlife research (East Melbourne), ISSN 1035-3712, E-ISSN 1448-5494, Vol. 35, no 4, p. 59-64Article in journal (Refereed)
    Abstract [en]

    In previous work, we have shown that tadpoles of invasive cane toads (Bufo marinus) strongly avoid scent cues from crushed conspecific tadpoles. Thus, identifying the identity of the chemical involved may provide novel approaches to toad control, by manipulating the behaviour of toad tadpoles. A first step in the search for that chemical is to see whether toad tadpoles are similarly repelled by chemical cues from crushed tadpoles of other species. Our experimental trials with four native Australian frogs (three hylids, one myobatrachid) show that toads do not respond to chemical cues from these taxa. Hence, the specific chemicals that induce avoidance cannot be generic ones (e.g. body fluids, tissue fragments) but instead, must reflect some underlying chemical divergence in body composition between the tadpoles of cane toads versus the other anurans that we have tested.

  • 82.
    Hagman, Mattias
    et al.
    Univ Sydney, Sch Biol Sci, Sydney, NSW 2006, Australia.
    Shine, Rick
    Univ Sydney, Sch Biol Sci, Sydney, NSW 2006, Australia.
    Deceptive digits: the functional significance of toe waving by cannibalistic cane toads (Bufo marinus)2008In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 75, p. 123-131Article in journal (Refereed)
    Abstract [en]

    Many ambush foraging predators possess specialized structures and behaviours that plausibly function to attract prey, but this hypothesis has rarely been subject to direct empirical tests. If luring evolved to attract specific prey types then we predict that it will be manifested only if that prey type is present, and only by predators of the size class that feed on that prey type. Also, luring should induce closer approach by prey; and aspects of the behaviour (e. g. frequency of movement of the lure) should have been. ne tuned by selection to induce maximal response from prey. We describe a novel luring system: small- and medium-sized ( but not metamorph and large) cane toads, Chaunus marinus, wave the long middle toe of the hind-foot up and down in an obvious display. In keeping with the functional hypothesis, toe waving is elicited by moving edible-sized objects such as crickets or metamorphic toads. Metamorphic toads are attracted to this stimulus, and trials with a mechanical model show that both the colour and the vibrational frequency of the toe correspond closely with those most effective at attracting smaller conspecifics towards the lure. The independent evolution of visual luring systems in many animal lineages provides a powerful opportunity for robust empirical tests of adaptive hypotheses about signal design.

  • 83.
    Hakansson, Franziska
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. University of Copenhagen.
    Effect of daytime and age on the avoidance and approach behaviour of commercial Danish broiler chicken2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As activity levels of intensively managed broiler chicken vary over time, detailed knowledge on their influence is potentially useful to further adjust welfare assessment schemes. Therefore, this study investigated the influence of daytime and age on the performance of broiler chicken in two applied fear tests.On-farm studies were carried out in 14 flocks of intensively managed broiler chicken. A forced and a voluntary approach test were conducted during morning and evening hours and at three different ages (1: 6-12d; 2: 21-24d; 3: prior to slaughter). At each observation, avoidance distances (AD) and the number of animals voluntarily approaching (VA) an observer were collected.No significant correlation was found between daytime and AD or VA. When tested at different ages, daytime and VA were significantly correlated (1: r= 0.56*; 2: r= 0.40*; 3: r= 0.64*), but the results were not consistent. At three weeks the VA was found to be higher in the morning but at younger age and prior to slaughter, more birds approach an observer in the evening. Both, approach and avoidance peaked at three weeks and decreased prior to slaughter. Further, the effect of differing observer locations in the chicken house on the behavioural response of broiler chicken was studied. A higher proportion of birds voluntarily approached an unknown human in the area close to the main entrance door, but the avoidance behaviour was not affected.From the results of this study I conclude, that the time of assessment has no effect on avoidance or approach behaviour of commercial slow-growing broiler chicken. However, fear related behaviour changed depending on age. This makes the applied tests potentially applicable independent of daytime restrictions when performed with birds of the same age.

  • 84.
    Hanson, Michaela
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Facial expressions and other behavioral responses to pleasant and unpleasant tastes in cats  (Felis silvestris catus)2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The behavior and facial expressions performed by cats have been reported to be visibly affected by the perceived taste quality of a food item. The goal of the present study was to assess how cats react to pleasant and unpleasant tastes. The facial and behavioral reactions of 13 cats to different concentrations of L-Proline and quinine monohydrochloride as well as mixtures with different concentrations of the two substances were assessed using a two-bottle preference test. The cats were videotaped during the tests and the frequency and duration of 50 different behaviors was analyzed in Noldus the Observer XT. The cats responded to tastes regarded as pleasant by having their eyes less than 50 % open for significantly longer periods of time compared to a water control. Tongue protrusions were also observed significantly more frequently when the cats sampled from a solution with a preferred taste compared to a water control. When encountering solutions of quinine monohydrochloride or mixtures containing quinine monohydrochloride the cats were observed to perform tongue protrusion gapes much more frequently compared to a water or L-Proline control. Even though the cats did not significantly differ in the number of times they licked at spouts containing the 50 mM L-Proline and 500 mM quinine monohydrochloride mixture compared to a 50 mM L-Proline, no masking effect could be confirmed as there was no increase in the acceptance of the mixture was observed. The present study suggests that the knowledge about behavioral responses to pleasant or unpleasant taste can be utilized in future studies on how cats perceive different tastes.

  • 85.
    Hansson, Jessica
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Does the wolf (Canis lupus) affect presence of the red fox (Vulpes vulpes) in Sweden?2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vargen (Canis lupus) har ökat stadigt i Sverige under de senaste decennierna. Vargens återkomst och dess påverkan på det svenska djurlivet studeras idag i stor utsträckning, och frågor har uppstått om vargen som toppredator kan komma att orsaka trofiska kaskader i ekosystemet, vilket har observerats i nationalparker i USA. Rödräven (Vulpes vulpes) har i Sverige visat sig dra stor nytta utav vargens återkomst genom den ökade mängden kadaver som vargen lämnar, vilket är en särskilt viktig födokälla under våren.

    Syftet med denna studie var att undersöka om närvaro av varg påverkar förekomst av rödräv. Rävspår räknades i 182 vilttrianglar i Örebro och Värmlands län under åren 2001-2003. Vilttrianglarna klassificerades med avseende på mängd jordbruksmark, avstånd till vargrevir och ålder på vargrevir. Effekt av varg på rävförekomst analyserades genom att jämföra rävspår med distans till vargrevir och hur länge det funnits varg i området samt rävspår i relation till mängd jordbruksmark. Studien kunde inte påvisa någon effekt av vargförekomst på räv.  Resultaten indikerar på att habitatet var nyckelfaktorn för rävförekomst istället för närvaro av varg. I och med att vargstammen ökar stadigt i Sverige är det dock av intresse med fortsatta studier i ämnet då vargen kan komma att spela en större roll i ekosystemet i framtiden.

  • 86.
    Hartvig, Ditte L.
    et al.
    Danmark.
    Hausner, Helene
    Danmark.
    Wendin, Karin
    Kristianstad University, School of Education and Environment, Avdelningen för Praktisk-estetiska ämnen. Kristianstad University, Resrarch environment Food and Meals in Everyday Life (MEAL).
    Ritz, Christian
    Danmark.
    Bredie, Wender L. P.
    Danmark.
    Initial liking influences the development of acceptance learning across repeated exposure to fruit juices in 9–11 year-old children2015In: Food Quality and Preference, ISSN 0950-3293, E-ISSN 1873-6343, Vol. 39, p. 228-235Article in journal (Refereed)
    Abstract [en]

    In several studies, it has been found that repeated exposure to a novel food increases children’s acceptance of the exposure food. The present study, investigated how repeated exposure influences the acceptance of two Nordic berry juices, and whether the development depends on initial liking of the product, in 9–11 year-old children. The study had 317 participants. Two groups of children were exposed to either sea-buckthorn (n = 92) or aronia (n = 105) juice eight times, and performed two follow-up sessions 3 and 6 months after the 8th exposure. A third group (n = 120) served as controls. During pre and post-test sessions all participating children evaluated acceptance of both juices.

    Intake of sea-buckthorn juice increased significantly over the eight exposures (55.1 ± 7.3 till 108.8 ± 12.3) and remained high after 6 months (131.1 ± 13.2). Intake of aronia juice was only increased at follow-up sessions. Liking did not develop significantly for any of the juices across exposures. When children were grouped by their initial liking increased intake across exposures was observed regardless of initial liking of sea-buckthorn. Liking developed similarly for both juices. A significant increase was found for the ‘initial dislikers’ only. This study demonstrates how exposure effects are influenced by initial liking; it appears that changes in familiarity explain the changes seen for sea-buckthorn among ‘dislikers’. ‘Initial dislikers’ had the most benefit from repeated exposures, but did not reach ‘initial likers’ across eight exposures; more exposures in the group of ‘initial dislikers’ had possibly led to even higher liking and intake. The increased intake observed for ‘neutral likers’ and ‘initial likers’ of sea-buckthorn was not explained by increased familiarity or increased liking.

  • 87.
    Hatchett, William
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    The road toward sympatric speciation in whitefish.: The effects of divergent selection on European whitefish (Coregonus lavaretus) size and behavior, and effects on zooplankton communities.2015Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    For almost every organism there are large gaps in our knowledge about the processes that leads to speciation. The changes an organism undergoes before divergence has occurred have remained a mystery, as it is difficult to say whether or not a species is going to diverge and when. To investigate this unknown the European whitefish (Coregonus lavaretus) and the northern pike (Esox lucius) were studied, as they produce a repeatable and predictable pattern of speciation in sympatry. To investigate the changes in phenotypes and behaviour in whitefish that precedes divergence, two lake populations were examined, Gräsvattnet and Ringsjön. Gräsvattnet was used as a control, with a population of whitefish but an absence of pike, whereas Ringsjön has a population of whitefish that invaded from Gräsvattnet and a pike population. The presence of pike presumably exerts divergent selection on the whitefish population. Fish and zooplankton were surveyed in both lakes from 1970 to the present day, which allows us to compare how whitefish populations and their resources change in the presence and absence of pike. The results found in Ringsjön show; (1) a change in habitat use, (2) a change in diet from pelagic to benthic, (3) an increase in the relationship between individual body size and diet and (4) a decrease in average size over the course of the study. (1)The presence of pike is believed to have forced the whitefish into the pelagic which could be seen in the result, with an increase in individuals caught in the pelagic. (2) The change in diet is thought to be caused by a resource competition created by individuals being forced to use the pelagic. Although insignificant this led to an overall reduction in zooplankton abundance by almost 40% which could have intensified competition. The resource competition could then have been intensified further by the change in composition of zooplankton relative abundance. (3) The increase in relationship between individual body size and diet is thought to increase due to the resource competition between smaller and larger individuals in the pelagic. Smaller individuals are better competitors than larger individuals for pelagic resource which could have led to the larger individuals switching to a more benthic diet. (4) The decrease in average size is thought to be caused by negative selection for larger individuals. Larger individuals have switched to a more benthic diet, and although the individuals are larger they still face the risk of predation in the littoral zone as they have not outgrown the gape size of the pike. This could have led to the average size reduction that may be the first steps in speciation, and ultimately leading to the divergence of two morphs by sympatric speciation in Ringsjön. In Gräsvattnet over the course of the study there were few and small changes in whitefish size, zooplankton relative abundance in the diet and in the environment. The results in Gräsvattnet could however suggest resource competition for benthic resources. Although resource competition is thought to be an important factor in the speciation of whitefish, without predation pressure no speciation occurs. This result could suggest the importance of predation pressure in the speciation of whitefish. 

  • 88.
    Hedlund, Louise
    Linköping University, Department of Physics, Chemistry and Biology, Zoology. Linköping University, The Institute of Technology.
    Personality and production in dairy cows2013Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Variation in animal personality, in other words, behavioural responses consistent within individuals over time and/or across contexts, is predicted to be related to life-history traits, such as growth rate and investment in reproduction. How this translates into relationships between personality and milk production in dairy cows is however scarcely investigated and previous studies are showing contradicting results. To further investigate this relationship, individual consistencies in behaviour were related to milk production in two breeds of dairy cows (Swedish red and white cattle, SRB, and Holstein). Variation was found among the breeds in consistency of behaviours and both SRB and Holstein cows were highly consistent over time in stepping behaviour during milking and frequency of performed abnormal behaviours in home pen. Overall were Holstein cows consistent in more observed behaviours than SRB. Variation in neophobia and responses to social separation were more flexible, both among breeds and over time. Nevertheless, behaviour showed limited relationship with milk production. To conclude, the tests here carried out are useful in describing personality in cows; however, personality showed no relationship with milk production, encouraging future studies to explore this expected relationship further in other breeds and species.

  • 89.
    Heurlin, Jasmine
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Behavioral synchronization between dogs and owners.2019Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Dogs have lived with us for thousands of years, so we have learned to understand one another. Dogs have been shown to synchronize their behavior with humans. Behavioral synchronization is characterizes by doing the same thing at the same time and in the same place as someone else. This synchronization is often dependent on the relationship and the emotional state of the individuals. The main aim in this study was to develop a method to test behavioral synchronization and also to investigate how this, but also other behaviors, are effect by preceding human-dog interactions. Privately owned dogs (N=21) were tested with three different treatments (play, pet or ignore). The test procedure consisted of the owner walking or standing still in a predefined pattern, while their dog was freely roaming. This study showed that dogs adapted their movement pattern to their owners. This was similar to previous studies showing that the method developed can be used to test behavioral synchronization between owner and dog. Dogs explored the test arena less after play interaction and they also tended to seek more eye contact with their owners, but the interactions did not affect how much time spent in human proximity, how much they followed them or on dogs movement pattern.

  • 90.
    Heydorn, Per
    Kristianstad University, Faculty of Natural Science.
    Inbreeding decreases upwind pheromone: mediated male flight and frequency in female calling behavior in a lab culture of the pyraloid moth Plodia interpunctella2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Semiochemicals are chemicals used to communicate. Animals tend to use these e.g. to locate food sources or to find a suitable mate. In this study, the sex pheromone of the Indian meal moth, Plodia interpunctella, was analysed. Since this is an economically important species, it is mass-reared in labs and science centers worldwide for experimental purposes. A culture of these moths was brought into the lab at Lund University for studies and has after that served as a model species demonstrating up-wind pheromone-mediated male flight in different courses held by the university. As years went by, the culture got less successful in up-wind flights, most probably because of inbreeding and bottleneck effects, and therefore, a new culture was taken in. This study focuses on using various experiments to see if there was a behavioral and/or physiological difference between the two cultures. Results show a significant difference in behavioral traits (frequency of calling behavior in females and in male up-wind flights) but not in physiological traits (female pheromone production or male antennal response). This study discusses some effects of mass-reared lab cultures.

  • 91.
    Hiltunen, Seppo
    et al.
    University of Helsinki, Finland.
    Virta, Maarit
    University of Helsinki, Finland.
    Kallio, Sakari
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre. University of Turku, Finland.
    Paavilainen, Petri
    University of Helsinki, Finland.
    The effects of hypnosis and hypnotic suggestions on the mismatch negativity in highly hypnotizable subjects2019In: International journal of clinical and experimental hypnosis, ISSN 0020-7144, E-ISSN 1744-5183, Vol. 67, no 2, p. 192-216Article in journal (Refereed)
    Abstract [en]

    The neural mechanisms associated with hypnosis were investigated in a group of 9 high hypnotizable subjects by measuring the mismatch negativity (MMN) component of the auditory eventrelated potential (ERP). ERPs were recorded using a passive oddball paradigm to sinusoidal standard and deviant tone stimuli of 500 and 520 Hz, respectively, in four conditions: prehypnosis, neutral hypnosis, hypnotic suggestion for altering the tone perception, and posthypnotic conditions. Earlier studies have indicated that hypnosis and hypnotic suggestions might have an effect on MMN, but the results of our study contradict these results: No statistically significant differences were found between the conditions in the MMN amplitudes.

  • 92.
    Hottges, Nina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Hjelm, Madeleine
    Boras Djurpk, Sweden.
    Hard, Therese
    Boras Djurpk, Sweden.
    Laska, Matthias
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    How does feeding regime affect behaviour and activity in captive African lions (Panthera leo)?2019In: JOURNAL OF ZOO AND AQUARIUM RESEARCH, ISSN 2214-7594, Vol. 7, no 3, p. 117-125Article in journal (Refereed)
    Abstract [en]

    Lions (Panthera leo) are popular zoo animals and obligate carnivores. In the past, zoos focused on the nutritional aspect of feeding, whereas today they also aim to encourage naturalistic feeding opportunities. AZAs Lion Care Manual recommends a frequent feeding schedule, while other sources highlight the benefits of unpredictable, infrequent feeding schedules. Further, the husbandry guidelines for lions by EAZA propose to feed lions separately. To assess how lions are affected by feeding frequency, we collected data on five event behaviour categories (social affiliative, agonistic, exploratory, marking, maintenance) and four state behaviour categories (inactive, active, feed, pace) of four captive lion prides held on either high frequency (HF: feeding pieces of meat on four to five occasions per week) or low frequency feeding (LF: feeding a whole carcass on one occasion per week). We found that some event behaviour categories (agonistic, exploratory and marking) and one state behaviour (feeding) were more frequent for lions on HF feeding. Lions on both feeding regimes engaged more often in agonistic behaviour and were more inactive on feeding days than fasting days. On fasting days, activity and pacing, as well as exploratory, maintenance, marking and social behaviour, were more frequent than on feeding days. During the consecutive fasting days, the lions on LF feeding were increasingly active in terms of walking, trotting and running. The results show that LF feeding with whole carcasses allowed the prides to resolve social discrepancies during feeding, which reduced aggression between feedings. LF feeding resulted in satiety of the lions to the extent of altered behaviour during feeding day and the first fasting day, whereas lions on HF feeding showed unvarying behaviour during feeding and fasting days suggesting a lack of satiety.

  • 93.
    Huq, Md. Nazmul
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    The genetic basis of a domestication trait in the chicken: mapping quantitative trait loci for plumage colour2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Domestication is the process by which animals become adapted to the environment provided by humans. The process of domestication has let to a number of correlated behavioural, morphological and physiological changes among many domesticated animal species. An example is the changes of plumage colour in the chicken. Plumage colour is one of the most readily observable traits that make distinction between breeds as well as between strains within a breed. Understanding the genetic architecture of pigmentation traits or indeed any trait is always a great challenge in evolutionary biology. The main aim of this study was to map quantitative trait loci (QTLs) affecting the red and metallic green coloration in the chicken plumage. In this study, a total of 572 F8 intercross chickens between Red Junglefowl and White Leghorn were used. Phenotypic measurements were done using a combination of digital photography and photography manipulating software. Moreover, all birds were genotyped with 657 molecular markers, covering 30 autosomes. The total map distance covered was 11228 cM and the average interval distance was 17 cM. In this analysis, a total of six QTLs (4 for red and 2 for metallic green colour) were detected on four different chromosomes: 2, 3 11 and 14. For red colour, the most significant QTL was detected on chromosome 2 at 165 cM. An additional QTL was also detected on the same chromosome at 540 cM. Two more QTLs were detected on chromosomes 11 and 14 at 24 and 203 cM respectively. Additionally, two epistatic pairs of QTLs were also detected. The identified four QTLs together can explain approximately 36% of the phenotypic variance in this trait. In addition, for metallic green colour, one significant and one suggestive QTLs were detected on chromosomes 2 and 3 at 399 and 247 cM respectively. Moreover, significant epistatic interactions between these two QTLs were detected. Furthermore, these two QTLs together can explain approximately 24% of the phenotypic variance in this trait. These findings suggest that the expression of pigmentation in the chicken plumage is highly influenced by both the epistatic actions and pleiotropic effects of different QTLs located on different chromosomes.

  • 94. Härlin, Mikael
    Humor gör oss osjälviska: Därför bör du skämta mer på jobbet2014In: Modern Psykologi, ISSN 2000-4087, no 7, p. 35-35Article in journal (Other (popular science, discussion, etc.))
  • 95.
    Jansson, Emelie
    Linköping University, Department of Physics, Chemistry and Biology.
    Influences of environment and personality on cognitive judgment bias in chickens2015Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Cognitive processes include biases, such as cognitive judgment bias. Cognitive judgment bias influences how the surrounding is interpreted, and this can differ between individuals. However, thus far no formal framework exists to understand how cognitive judgment bias works. Here I investigated how environmental factors and personality influence cognitive judgment bias in Gallus gallus chicks. First I investigated how two environmental factors affected the cognitive judgment bias of laying hen chicks. Chicks were exposed to stress and/or environmental enrichment, and tested in a cognitive judgment bias test before and after collective unpredictable stressors were presented. The results showed that chicks living in enriched environments were faster to reach all cues after the collective stressors than chicks living in non-enriched environments. Individual differences are often observed in animals, even when raised under identical conditions; therefore I also investigated if variation in personality influence cognitive judgment bias. Red junglefowl chicks were thereby raised in equal environments and exposed to personality assays in addition to a cognitive judgment bias test. I demonstrated that less nervous chicks were more optimistic towards ambiguous and negative cues than more nervous chicks. Also previous studies have found indications of connections between cognitive bias and environment or personality. I conclude that environmental enrichment can buffer the influence of stress on cognitive judgment bias and that personality has a small influence on interpretations of stimuli. In the future, experiments in this field should focus on exploring more aspects on how cognitive biases occurs to improve our understanding of cognitive processes.

  • 96.
    JEAN-LOUIS, Uranie
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Effect of sensory enrichments on the behaviour of captive Northern lynx (Lynx lynx lynx) and assessment of automated behaviour monitoring technologies2019Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Captive environments like zoo exhibits offer limited space, lacking many of the environmental stimuli that are present in the wild. This may reduce animal welfare and potentially lead to the development of stereotypic behaviour like pacing. Environmental enrichment is used to prevent and reduce pacing and enhance animal well-being. The aim of this project was to evaluate sensory enrichments, and the effect of such enrichment on pacing in a group of Northern lynx by means of new, automated monitoring technologies in combination with traditional visual observations. The lynxes were exposed to valerian, catnip and cinnamon as olfactory enrichment. The acoustic enrichments were play-backed mouse squeals, roe deer barking and lynx vocalizations, and live crickets. The responses of the lynx were recorded by logging their subcutaneous HDX pit tags, and Bluetooth Low Energy (BLE) tags mounted on collars and using a wildlife camera. The results showed that catnip elicited clear “catnip responses” i.e sniffing, rubbing, biting and licking. The sounds were found to attract the lynxes and increase their arousal. One of the sounds, the lynx calls, elicited social behaviour. However, none of the sensory treatments reduced pacing. The combination of these automated technologies with visual observation was powerful to evaluate the effect of enrichment on captive lynxes and to monitor their activity patterns and stereotypic behaviours. Sensory enrichment could also be used in the wild as lures to attract lynxes to BLE or HDX PIT tag logging stations and to wildlife cameras, as part of monitoring a lynx population. 

  • 97.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Hunden som skäms: myt eller sanning?2014Book (Other academic)
    Abstract [sv]

    Hundar har en unik förmåga att förstå och kommunicera med oss människor, utvecklad under årtusenden av nära samliv. Faktum är att de på många sätt förstår oss bättre än vad vi själva gör. Under senare år har forskarna på allvar börjat glänta på dörren till hundarnas inre liv. Vi har lärt oss att deras tankar och känslor framförallt kretsar runt en sak: relationen till människor.

    Här kan du läsa om de nya rönen kring hundarnas intelligens och känsloliv. Skäms de verkligen när de gjort något förbjudet? Har de sinne för rättvisa och blir de svartsjuka? Hur ser deras tidsuppfattning ut? Hur mycket förstår de av vårt språk? De nya insikterna i hundarnas innersta tankar gör det svårt att någonsin betrakta dem på samma sätt igen.

  • 98.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Zoology. Linköping University, The Institute of Technology.
    Transgenerational epigenetic effects on animal behaviour2013In: Progress in Biophysics and Molecular Biology, ISSN 0079-6107, E-ISSN 1873-1732, Vol. 113, no 3, p. 447-454Article, review/survey (Refereed)
    Abstract [en]

    Over the last decade a shift in paradigm has occurred with respect to the interaction between environmentand genes. It is now clear that animal genomes are regulated to a large extent as a result of inputfrom environmental events and experiences, which cause short- and long-term modifications in epigeneticmarkings of DNA and histones. In this review, the evidence that such epigenetic modificationscan affect the behaviour of animals is explored, and whether such acquired behaviour alterations cantransfer across generation borders. First, the mechanisms by which experiences cause epigenetic modificationsare examined. This includes, for example, methylation of cytosine in CpG positions and acetylationof histones, and studies showing that this can be modified by early experiences. Secondly, theevidence that specific modifications in the epigenome can be the cause of behaviour variation isreviewed. Thirdly, the extent to which this phenotypically active epigenetic variants can be inheritedeither through the germline or through reoccurring environmental conditions is examined. A particularlyinteresting observation is that epigenetic modifications are often linked to stress, and may possibly bemediated by steroid effects. Finally, the idea that transgenerationally stable epigenetic variants may serveas substrates for natural selection is explored, and it is speculated that they may even predispose fordirected, non-random mutations.

  • 99.
    Johanna, Axelsson
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Turn-taking in interspecies vocal communication: A study of dog-human interactions2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Dogs are well adapted to a life close to humans and are capable of understanding several human social cues. Turn-taking is a fundamental phenomenon in human conversations, yet no research of turn-taking in interspecies vocal communication has been done. This pilot study therefore aimed to develop a test method in order to analyze if turn-taking occurs in interspecies vocal communication between dogs and humans and if turn-taking can be correlated with specific behaviors in dogs. By analyzing a vocal conversation between seven dogs and their owners during a request situation in their home environment, this study found support for turn-taking existence in dog-human vocal communications. In general, owner-dog vocal communication could be linked to positive events, such as tail wagging and eye contact. Meanwhile, a lower frequency of vocal turn- taking could be linked to stress related behaviors, such as lip licking. Owner in dyads where more vocal overlap occurred tended to score the owner-dog relationship and communication abilities with lower grades, suggesting the absence of turn-taking was experienced as unpleasant for the owner as well. In conclusion, findings from current study highlight the unique coevolution of dogs and humans and opens up for future research of turn-taking in interspecies vocal communication.

  • 100.
    Johansen, Aleksandra I.
    Stockholm University, Faculty of Science, Department of Zoology.
    Seasonal change in defensive coloration in a shieldbug2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Protective coloration such as aposematism and crypsis occurs in many insects but only a few species alter their defensive strategy during the same instar. We hypothesize the adult shield bug Graphosoma lineatum with an alternating black and non-melanised longitudinal striation exhibit such a change in defensive coloration. In Sweden, the non-melanised stripes of the pre-hibernation G. lineatum are pale brown and cryptic but they change during hibernation to red and aposematic. We have tested the adaptive functions of coloration of the two G. lineatum forms against bird predators. In Paper I we used great tits as predators and measured detection time of the two forms against a background of dry grass and plants, simulating late-summer conditions. We found that the birds took longer time to find the pale than the red form. Thus, the pale form of G. lineatum is more cryptic in a dry environment than the red form. In Paper II and III we used naïve predators and measured attack rate/latency on red and pale adults and fifth-instar larvae (black and brown) to investigate avoidance and generalisation between the stages. In Paper II domestic chicks initially found the red form most intimidating, but both adult forms are more intimidating than the larva. Moreover, there was a broad generalisation among forms. In Paper III naïve great tits did not find the red form significantly more aversive than the pale adult. Neither the chicks nor the tits showed any difference in the speed of avoidance learning between the two adult colour forms. In Paper IV the shieldbugs themselves were the main focus as we compared activity levels in the different colour forms and found that G. lineatum alters behaviour in accordance to their protective strategy. Thus they were significantly less active during the cryptic phase. Taken together, these experiments suggest that the pale brown adult invests in a cryptic strategy at the cost of reduced protection from aposematism, whereas the red adult benefits from aposematism at the cost of reduced camouflage.

123456 51 - 100 of 281
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf