Geographic Variation in Agonistic Responses of Territorial Male Brook Sticklebacks, Culae Inconstans

Author Institution: Department of Biology, Wilmington College ; Department of Biology, Earlham CollegeTerritorial aggressive behavior was studied in male brook sticklebacks collected in Saskatoon, Saskatchewan; Oshkosh, Wisconsin; Ft. Atkinson, Wisconsin, and Urbana, Ohio. In the 20 h of observation 1,167 individual encounters with 3,305 separate aggressive displays were observed. Aggressive behavior was observed to be complex with at least 12 distinct aggressive display postures observed

Species-specific differences and similarities in the behavior of hand-raised dog and wolf pups in social situations with humans

In order to reveal early species-specific differences, we observed the behavior of dog puppies (n = 11) and wolf pups (n = 13) hand raised and intensively socialized in an identical way. The pups were studied in two object-preference tests at age 3, 4, and 5 weeks. After a short isolation, we observed the subjects' behavior in the presence of a pair of objects, one was always the subject's human foster parent (caregiver) and the other was varied; nursing bottle (3 weeks), unfamiliar adult dog (3 and 5 weeks), unfamiliar experimenter (4 and 5 weeks), and familiar conspecific age mate (4 weeks). Dogs and wolves did not differ in their general activity level during the tests. Wolf pups showed preference for the proximity of the caregiver in two of the tests; Bottle-Caregiver at the age of 3 weeks and Experimenter-Caregiver at the age of 5 weeks, while dogs showed preference to the caregiver in three tests; conspecific Pup-Caregiver and Experimenter-Caregiver at the age of 4 weeks and dog-caregiver at the age of 5. Compared to wolves, dogs tended to display more communicative signals that could potentially facilitate social interactions, such as distress vocalization, tail wagging, and gazing at the humans' face. In contrast to dog puppies, wolf pups showed aggressive behavior toward a familiar experimenter and also seemed to be more prone to avoidance. Our results demonstrate that already at this early age-despite unprecedented intensity of socialization and the comparable social (human) environment during early development-there are specific behavioral differences between wolves and dogs mostly with regard to their interactions with humans

On the effects of domestication on canine social development and behavior

Social development and behavior are compared for 4 Eastern timber wolves (C. lupus lycaon) and 4 Alaskan Malamutes (C. familiaris). The two groups were born a year apart, but all were fostered at approximately 10 days of age on the same lactating female wolf, reared jointly by the authors and the foster mother, housed in the same facility, and subjected to the same regimen of maintenance and social contact with adult members of the animal colony. It is suggested that many of the observed group differences can be attributed to selection in domestic dogs for prolongation of juvenile behavior and morphological characteristics. Discussion then focuses on the evolution and ontogeny of ritualized aggression in wolves and the effects of domestication on agonistic behavior in domestic dogs. It is suggested that the disintegration of ritualized aggression in dogs is, in part, a consequence of neotenization. Also implicated in the breakdown of this behavioral system is human provision of food, which relaxes (1) the behavioral consequences of injuries sustained in fighting and (2) the selective advantage enjoyed by group-hunting species who have evolved social systems of population regulation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23918/1/0000163.pd