Abstract: Learning differences predicted from ecological variables can be confounded with differences in wariness of novel stimuli (neophobia). Previous work on feral pigeons (Columba livia), as well as on group-feeding and territorial zenaida doves (Zenaida aurita), reported individual and social learning differences predicted from social foraging mode. In the present study, we show that speed of learning a foraging task covaries with neophobia and latency to feed from a familiar dish in the three types of columbids. Pigeons were much faster than either territorial or group-feeding zenaida doves on all tests conducted in captivity, but showed unexpectedly strong neophobia in some urban flocks during field tests. Human proximity strongly affected performance in group-feeding doves both in the field and in captivity. They were slightly faster at learning than their territorial conspecifics in cage tests. In multiple regressions, species identity, but not social foraging mode, significantly predicted individual variation in learning, as did individual variation in neophobia. Wariness of novel stimuli and species differences associated with artificial selection appear to be more important than foraging mode and wariness of humans in accounting for learning differences between these columbids.

Abstract: Among the most social of all canids, the endangered African wild dog lives in packs in which the alpha pair typically monopolizes breeding while nonreproductive members help care for the offspring. Consequently, the size of the breeding population is directly related to the number of packs in the population. Although the formation of new packs affects both individual fitness and population dynamics, little is known about the process of pack formation and the proximate factors that influence the outcome. In this paper, seven cases of attempted pack formation are documented, of which four failed. Three possible explanations for pack annulment are considered: group size, mate competition, and mate choice (i.e. group compatibility). Our observations suggest that group compatibility can influence whether stable reproductive units form. The influence of individual behavior, via the process of pack formation, on population dynamics is discussed. The potential conservation application of the theoretical study of wild dog pack formation is highlighted.

Abstract: The status of the Gobi khulan Equus hemionus subsp. is recorded as “insufficiently known” in the Species Survival Commission's Equid Action Plan. Recent counts confirm that Mongolia holds the most important population of the whole species. Since 1953, the animals have benefited from a protected status, but this is now challenged. A 5-year study in the B part of the Gobi National Park on one subpopulation showed that it has remained stable over the past 15 years with an adequate mean reproductive rate of 15% and a 50% survival rate over the first year. Age/sex related mortality and prey analysis indicate that wolf predation probably has some impact on the population, in particular for 4-6-year-olds of both sexes at the start of reproduction. Desert and mountain steppes are the khulan's year-round preferred habitat, but `oases', play an important role at the beginning of lactation. Anthropogenic factors affect both home range and habitat use through direct intervention or permanent occupation of the scarce water sources. Khulans of this subpopulation, unlike other Asian and African wild asses, form year-round stable, non-territorial families. These families and all-male groups join together into “bands” in winter, and herds of several hundred animals, where reproductive rate is highest, form throughout the year. The existence of such herds may thus be critical for the breeding success of the population. Our study provides the first detailed quantitative data for this subspecies, which will help to monitor changes in the future.

Abstract: Studies of vocal development in nonhuman primates have found little evidence for plasticity in vocal production, somewhat more for usage of calls, with the greatest plasticity arising in response to calls of others. Generally, similar results were obtained with callitrichid monkeys, the marmosets and tamarins, but with several interesting exceptions. Infant pygmy marmosets show babbling behavior with improvement in adult call structure related to the amount and diversity of babbling. Adult marmosets alter call structure in response to changes in social partners, and wild marmosets have vocal dialects and modify call structure according to how far they are from other group members, suggesting the potential to modify call structure in different social and environmental contexts, though direct learning of novel vocalizations has not been observed. Infant cotton-top tamarins do not produce adult-like calls in appropriate contexts, at least in the first few months of life, but through food sharing from adults infants learn about appropriate foods and the appropriate contexts for food vocalizations. Tamarins modify call structure and usage with changes in social status. Tamarins, unlike other monkeys tested, can learn to avoid noxious foods through observation of other group members, and can learn about novel food locations. Recent studies provide evidence of contextual imitation in marmosets. The plasticity in vocal communication and evidence of social learning in marmosets and tamarins relative to other monkeys may be related to the cooperative breeding system of marmosets and tamarins. With a high degree of behavioral coordination among group members, there is a priority on monitoring signals and behavior of others and adjusting one's own signals and behavior. This creates the context for vocal plasticity and social learning.