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B. Agnetta,, B. Hare,, & M. Tomasello,. (2000). Cues to food location that domestic dogs (Canis familiaris) of different ages do and do not use. Anim. Cogn., 3(2), 107–112.
Abstract: Autoren
B. Agnetta, B. Hare, M. Tomasello
Zusammenfassung
The results of three experiments are reported. In the main study, a human experimenter presented domestic dogs (Canis familiaris) with a variety of social cues intended to indicate the location of hidden food. The novel findings of this study were: (1) dogs were able to use successfully several totally novel cues in which they watched a human place a marker in front of the target location; (2) dogs were unable to use the marker by itself with no behavioral cues (suggesting that some form of human behavior directed to the target location was a necessary part of the cue); and (3) there were no significant developments in dogs' skills in these tasks across the age range 4 months to 4 years (arguing against the necessity of extensive learning experiences with humans). In a follow-up study, dogs did not follow human gaze into “empty space” outside of the simulated foraging context. Finally, in a small pilot study, two arctic wolves (Canis lupus) were unable to use human cues to locate hidden food. These results suggest the possibility that domestic dogs have evolved an adaptive specialization for using human-produced directional cues in a goal-directed (especially foraging) context. Exactly how they understand these cues is still an open question.
Schlüsselwörter
Key words Dogs – Arctic wolves – Social cognition – Gaze following – Communication
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Astié, A. A., Kacelnik, A., & Reboreda, J. C. (1998). Sexual differences in memory in shiny cowbirds. Anim. Cogn., 1(2), 77–82.
Abstract: Avian brood parasites depend on other species, the hosts, to raise their offspring. During the breeding season, parasitic cowbirds (Molothrus sp.) search for potential host nests to which they return for laying a few days after first locating them. Parasitic cowbirds have a larger hippocampus/telencephalon volume than non-parasitic species; this volume is larger in the sex involved in nest searching (females) and it is also larger in the breeding than in the non-breeding season. In nature, female shiny cowbirds Molothrus bonariensis search for nests without the male's assistance. Here we test whether, in association with these neuroanatomical and behavioural differences, shiny cowbirds display sexual differences in a memory task in the laboratory. We used a task consisting of finding food whose location was indicated either by the appearance or the location of a covering disk. Females learnt to retrieve food faster than males when food was associated with appearance cues, but we found no sexual differences when food was associated with a specific location. Our results are consistent with the view that parasitism and its neuroanatomical correlates affect performance in memory tasks, but the effects we found were not in the expected direction, emphasising that the nature of avian hippocampal function and its sexual differences are not yet understood.
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Fischer, J., & Hammerschmidt, K. (2001). Functional referents and acoustic similarity revisited: the case of Barbary macaque alarm calls. Anim. Cogn., 4(1), 29–35.
Abstract: Barbary macaques (Macaca sylvanus) utter “shrill barks” in response to disturbances in their surroundings. In some cases, the majority of group members react by running away or climbing up a tree. In many other instances, however, group members show no overt reaction to these calls. We conducted a series of playback experiments to identify the factors underlying subjects' responses. We presented calls given in response to dogs that had elicited escape responses and calls that had failed to do so. We also presented calls given in response to snakes and to the observer approaching the sleeping-trees at night. An acoustic analysis of the calls presented in the playback experiments (electronic supplementary material, audioclip S1) revealed significant differences among calls given in response to dogs, the observer approaching at night, and snakes. However, the analysis did not detect any differences between calls given in response to dogs that were related to whether or not they had elicited escape responses in the first place. Correspondingly, after playback of calls given in response to dogs, we observed no difference in subjects' responses in relation to whether or not the calls had initially elicited escape responses. Subjects showed startle or escape responses significantly more often after playbacks of calls given in response to dogs than after calls given in response to observers. Playbacks of calls given in response to snakes failed to elicit specific responses such as standing bipedally or scanning the grass. Although these findings may imply that responses depend on the external referent, they also indicate that there is no clear-cut relationship between the information available to the listeners and their subsequent responses. This insight forces us to extend current approaches to identifying the meaning of animal signals.
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Cole, P. D., & Adamo, S. A. (2005). Cuttlefish (Sepia officinalis: Cephalopoda) hunting behavior and associative learning. Anim. Cogn., 8(1), 27–30.
Abstract: Because most learning studies in cephalopods have been performed on octopods, it remains unclear whether such abilities are specific to octopus, or whether they correlate with having a larger and more centrally organized brain. To investigate associative learning in a different cephalopod, six sexually mature cuttlefish (Sepia officinalis) participated in a counterbalanced, within-subjects, appetitive, classical conditioning procedure. Two plastic spheres (conditioned stimuli, CSs), differing in brightness, were presented sequentially. Presentation of the CS+ was followed 5 s later by a live feeder fish (unconditioned stimulus, US). Cuttlefish began to attack the CS+ with the same type of food-acquisition seizures used to capture the feeder fish. After seven blocks of training (42 presentations of each CS) the difference in seizure probability between CS+ and CS- trials more than doubled; and was found to be significantly higher in late versus early blocks. These results indicate that cuttlefish exhibit autoshaping under some conditions. The possible ecological significance of this type of learning is briefly discussed.
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Zentall, T. R. (2005). Configural/holistic processing or differential element versus compound similarity. Anim. Cogn., 8(2), 141–142.
Abstract: Before accepting a configural or holistic account of visual perception, one should be sure that an analytic (elemental) account does not provide an equal or better explanation of the results. I suggest that when one forms a compound of a color and a line orientation with one element previously trained as an S+ and the other as an S-, the resulting transfer found will depend on the relative salience of the two elements, and most important, the similarity of the compound to each of the training stimuli. Thus, if a line orientation is placed on a colored background (a separable compound), it will appear more like the colored field used in training, and color will control responding. However, if the line itself is colored (an integral compound), the compound will appear more like the line used in training, and line orientation will control responding. Not only does this account do a better job of explaining the data but it is simpler and it is testable.
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Ducatez, S., Audet, J. N., & Lefebvre, L. (2013). Independent appearance of an innovative feeding behaviour in Antillean bullfinches. Anim. Cogn., 16(3), 525–529.
Abstract: Behavioural innovations have been largely documented in birds and are thought to provide advantages in changing environments. However, the mechanisms by which behavioural innovations spread remain poorly known. Two major mechanisms are supposed to play a fundamental role: innovation diffusion by social learning and independent appearance of the same innovation in different individuals. Direct evidence for the independent emergence of the same innovation in different individuals is, however, lacking. Here, we show that a highly localized behavioural innovation previously observed in 2000 in Barbados, the opening of sugar packets by Loxigilla barbadensis bullfinches, persisted more than a decade later and had spread to a limited area around the initial site. More importantly, we found that the same innovation appeared independently in other, more distant, locations on the same island. On the island of St-Lucia, 145 km from Barbados, we also found that the sister species of the Barbados bullfinch, the Lesser Antillean bullfinch Loxigilla noctis developed the same innovation independently. Finally, we found that a third species, the Bananaquit Coereba flaveola, exploited the bullfinches’ technical innovation to benefit from this new food source. Overall, our observations provide the first direct evidence of the independent emergence of the same behavioural innovation in different individuals of the same species, but also in different species subjected to similar anthropogenic food availability.
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Taubert, J., Weldon, K. B., & Parr, L. A. (2016). Robust representations of individual faces in chimpanzees (Pan troglodytes) but not monkeys (Macaca mulatta). Anim. Cogn., , 1–9.
Abstract: Being able to recognize the faces of our friends and family members no matter where we see them represents a substantial challenge for the visual system because the retinal image of a face can be degraded by both changes in the person (age, expression, pose, hairstyle, etc.) and changes in the viewing conditions (direction and degree of illumination). Yet most of us are able to recognize familiar people effortlessly. A popular theory for how face recognition is achieved has argued that the brain stabilizes facial appearance by building average representations that enhance diagnostic features that reliably vary between people while diluting features that vary between instances of the same person. This explains why people find it easier to recognize average images of people, created by averaging multiple images of the same person together, than single instances (i.e. photographs). Although this theory is gathering momentum in the psychological and computer sciences, there is no evidence of whether this mechanism represents a unique specialization for individual recognition in humans. Here we tested two species, chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta), to determine whether average images of different familiar individuals were easier to discriminate than photographs of familiar individuals. Using a two-alternative forced-choice, match-to-sample procedure, we report a behaviour response profile that suggests chimpanzees encode the faces of conspecifics differently than rhesus monkeys and in a manner similar to humans.
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Shepherd, S. V., & Platt, M. L. (2007). Spontaneous social orienting and gaze following in ringtailed lemurs (Lemur catta). Anim. Cogn., .
Abstract: Both human and nonhuman primates preferentially orient toward other individuals and follow gaze in controlled environments. Precisely where any animal looks during natural behavior, however, remains unknown. We used a novel telemetric gaze-tracking system to record orienting behavior of ringtailed lemurs (Lemur catta) interacting with a naturalistic environment. We here provide the first evidence that ringtailed lemurs, group-living prosimian primates, preferentially gaze towards other individuals and, moreover, follow other lemurs' gaze while freely moving and interacting in naturalistic social and ecological environments. Our results support the hypothesis that stem primates were capable of orienting toward and following the attention of other individuals. Such abilities may have enabled the evolution of more complex social behavior and cognition, including theory of mind and language, which require spontaneous attention sharing. This is the first study to use telemetric eye-tracking to quantitatively monitor gaze in any nonhuman animal during locomotion, feeding, and social interaction. Moreover, this is the first demonstration of gaze following by a prosimian primate and the first to report gaze following during spontaneous interaction in naturalistic social environments.
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Fripp, D., Owen, C., Quintana-Rizzo, E., Shapiro, A., Buckstaff, K., Jankowski, K., et al. (2005). Bottlenose dolphin (Tursiops truncatus) calves appear to model their signature whistles on the signature whistles of community members. Anim. Cogn., 8(1), 17–26.
Abstract: Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves' signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves' associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.
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Sommer, V., Lowe, A., & Dietrich, T. (2016). Not eating like a pig: European wild boar wash their food. Anim. Cogn., 19(1), 245–249.
Abstract: Carrying food to water and either dunking or manipulating it before consumption has been observed in various taxa including birds, racoons and primates. Some animals seem to be simply moistening their food. However, true washing aims to remove unpleasant surface substrates such as grit and sand and requires a distinction between items that do and do not need cleaning as well as deliberate transportation of food to a water source. We provide the first evidence for food washing in suids, based on an incidental observation with follow-up experiments on European wild boar (Sus scrofa) kept at Basel Zoo, Switzerland. Here, all adult pigs and some juveniles of a newly formed group carried apple halves soiled with sand to the edge of a creek running through their enclosure where they put the fruits in the water and pushed them to and fro with their snouts before eating. Clean apple halves were never washed. This indicates that pigs can discriminate between soiled and unsoiled foods and that they are able to delay gratification for long enough to transport and wash the items. However, we were unable to ascertain to which degree individual and/or social learning brought this behaviour about.
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