toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Range, F.; Bugnyar, T.; Schlogl, C.; Kotrschal, K. doi  openurl
  Title Individual and sex differences in learning abilities of ravens Type Journal Article
  Year 2006 Publication Behavioural Processes Abbreviated Journal (up) Behav. Process.  
  Volume 73 Issue 1 Pages 100-106  
  Keywords Animals; Behavior, Animal/*physiology; *Crows; Discrimination Learning/*physiology; Exploratory Behavior/physiology; Female; *Individuality; Male; Sex Factors; Spatial Behavior  
  Abstract Behavioral and physiological characteristics of individuals within the same species have been found to be stable across time and contexts. In this study, we investigated individual differences in learning abilities and object and social manipulation to test for consistency within individuals across different tasks. Individual ravens (Corvus corax) were tested in simple color and position discrimination tasks to establish their learning abilities. We found that males were significantly better in the acquisition of the first discrimination task and the object manipulation task, but not in any of the other tasks. Furthermore, faster learners engaged less often in manipulations of conspecifics and exploration of objects to get access to food. No relationship between object and social manipulation and reversal training were found. Our results suggest that individual differences in regard to the acquisition of new tasks may be related to personalities or at least object manipulation in ravens.  
  Address Konrad Lorenz Research Station, A-4645 Gruenau 11, Austria. friederike.range@univie.ac.at  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0376-6357 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16675158 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4146  
Permanent link to this record
 

 
Author Schloegl, C.; Kotrschal, K.; Bugnyar, T. url  doi
openurl 
  Title Modifying the object-choice task: Is the way you look important for ravens? Type Journal Article
  Year 2008 Publication Behavioural Processes Abbreviated Journal (up) Behav. Process.  
  Volume 77 Issue 1 Pages 61-65  
  Keywords Gaze; Modification; Object-choice task; Raven  
  Abstract Most animals seem to have difficulties in using gaze cues to find hidden food in object-choice tasks. For instance, chimpanzees usually fail in these tests, even though they are capable of following other's gaze geometrically behind barriers. Similar to chimpanzees, common ravens are skilled in tracking other's gaze but fail in object-choice tasks. We here explored whether procedural modifications, which had been used successfully in chimpanzees, would also yield positive results in ravens. In our modifications (a) the experimenter approached the cup while gazing at it, (b) the gaze cue was accompanied by a sound and (c) the experimenter could actually see the food while giving the gaze cue. Two out of seven birds performed above chance level in some of these conditions. However, we ascribe this improvement to the individuals' learning ability rather than to an understanding of the communicative nature of the task. This interpretation is further supported by results of a follow-up experiment suggesting that ravens may not rely on conspecifics' gaze cues for finding food caches in a natural foraging context. In sum, our results suggest that ravens may not transfer their gaze follow abilities to foraging situations involving hidden food.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4505  
Permanent link to this record
 

 
Author Fraser, O.N.; Bugnyar, T. url  doi
openurl 
  Title Do Ravens Show Consolation? Responses to Distressed Others Type Journal Article
  Year 2010 Publication PLoS ONE Abbreviated Journal (up) PLoS ONE  
  Volume 5 Issue 5 Pages e10605  
  Keywords  
  Abstract <sec> <title>Background</title> <p>Bystander affiliation (post-conflict affiliation from an uninvolved bystander to the conflict victim) may represent an expression of empathy in which the bystander consoles the victim to alleviate the victim's distress (“consolation”). However, alternative hypotheses for the function of bystander affiliation also exist. Determining whether ravens spontaneously offer consolation to distressed partners may not only help us to understand how animals deal with the costs of aggressive conflict, but may also play an important role in the empathy debate.</p> </sec><sec> <title>Methodology/Principal findings</title> <p>This study investigates the post-conflict behavior of ravens, applying the predictive framework for the function of bystander affiliation for the first time in a non-ape species. We found weak evidence for reconciliation (post-conflict affiliation between former opponents), but strong evidence for both bystander affiliation and solicited bystander affiliation (post-conflict affiliation from the victim to a bystander). Bystanders involved in both interactions were likely to share a valuable relationship with the victim. Bystander affiliation offered to the victim was more likely to occur after intense conflicts. Renewed aggression was less likely to occur after the victim solicited affiliation from a bystander.</p> </sec><sec> <title>Conclusions/Significance</title> <p>Our findings suggest that in ravens, bystanders may console victims with whom they share a valuable relationship, thus alleviating the victims' post-conflict distress. Conversely victims may affiliate with bystanders after a conflict in order to reduce the likelihood of renewed aggression. These results stress the importance of relationship quality in determining the occurrence and function of post-conflict interactions, and show that ravens may be sensitive to the emotions of others.</p> </sec>  
  Address  
  Corporate Author Thesis  
  Publisher Public Library of Science Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5195  
Permanent link to this record
 

 
Author Bugnyar, T.; Stöwe, M.; Heinrich, B. doi  openurl
  Title Ravens, Corvus corax, follow gaze direction of humans around obstacles Type Journal Article
  Year 2004 Publication Proceedings of the Royal Society B: Biological Sciences Abbreviated Journal (up) Proc. Roy. Soc. Lond. B Biol. Sci.  
  Volume 271 Issue 1546 Pages 1331-1336  
  Keywords  
  Abstract The ability to follow gaze (i.e. head and eye direction) has recently been shown for social mammals, particularly primates. In most studies, individuals could use gaze direction as a behavioural cue without understanding that the view of others may be different from their own. Here, we show that hand–raised ravens not only visually co–orient with the look–ups of a human experimenter but also reposition themselves to follow the experimenter's gaze around a visual barrier. Birds were capable of visual co–orientation already as fledglings but consistently tracked gaze direction behind obstacles not before six months of age. These results raise the possibility that sub–adult and adult ravens can project a line of sight for the other person into the distance. To what extent ravens may attribute mental significance to the visual behaviour of others is discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes 10.1098/rspb.2004.2738 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5009  
Permanent link to this record
 

 
Author Bugnyar, T. url  doi
openurl 
  Title Knower–guesser differentiation in ravens: others' viewpoints matter Type Journal Article
  Year 2011 Publication Proceedings of the Royal Society B: Biological Sciences Abbreviated Journal (up) Proc. Roy. Soc. Lond. B Biol. Sci.  
  Volume 278 Issue 1705 Pages 634-640  
  Keywords  
  Abstract Differentiating between individuals with different knowledge states is an important step in child development and has been considered as a hallmark in human evolution. Recently, primates and corvids have been reported to pass knower–guesser tasks, raising the possibility of mental attribution skills in non-human animals. Yet, it has been difficult to distinguish ‘mind-reading’ from behaviour-reading alternatives, specifically the use of behavioural cues and/or the application of associatively learned rules. Here, I show that ravens (Corvus corax) observing an experimenter hiding food are capable of predicting the behaviour of bystanders that had been visible at both, none or just one of two caching events. Manipulating the competitors' visual field independently of the view of the test-subject resulted in an instant drop in performance, whereas controls for behavioural cues had no such effect. These findings indicate that ravens not only remember whom they have seen at caching but also take into account that the other's view was blocked. Notably, it does not suffice for the birds to associate specific competitors with specific caches. These results support the idea that certain socio-ecological conditions may select for similar cognitive abilities in distantly related species and that some birds have evolved analogous precursors to a human theory-of-mind.  
  Address raven; Corvus corax; knowledge attribution; perspective; competitive food retrieval; caching  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5287  
Permanent link to this record
 

 
Author Heinrich, B.; Bugnyar, T. openurl 
  Title Just how smart are ravens? Type Journal Article
  Year 2007 Publication Scientific American Abbreviated Journal (up) Sci Am  
  Volume 296 Issue 4 Pages 64-71  
  Keywords Animals; *Behavior, Animal; Crows/*physiology; Environment; *Intelligence; Predatory Behavior; Problem Solving; Thinking  
  Abstract  
  Address University of Vermont, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-8733 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17479632 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4101  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print