Abstract: Primate sociality has received much attention and its complexity has been viewed as a driving force for the evolution of cognitive abilities. Improved analytic techniques have allowed primate researchers to reveal intricate social networks based on the exchange of cooperative acts and services. Although nonprimates are known to show similar behavior (e.g., cooperative hunting, food sharing, coalitions) there seems a consensus that social life is less complex than in primates. Here the authors present the first group-level analysis of reciprocity of social interactions in a social carnivore, the ring-tailed coati (<xh:i xmlns:search=“http://marklogic.com/appservices/search” xmlns=“http://apa.org/pimain” xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance” xmlns:xh=“http://www.w3.org/1999/xhtml”>Nasua nasua</xh:i>). The authors found that support in aggressive conflicts is a common feature in coatis and that this behavior is reciprocally exchanged in a manner seemingly as complex as in primates. Given that reciprocity correlations persisted after controlling for the effect of spatial association and subunit membership, some level of scorekeeping may be involved. Further studies will be needed to confirm our findings and understand the mechanisms underlying such reciprocity, but our results contribute to the body of work that has begun to challenge primate supremacy in social complexity and cognition. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

Abstract: This review examines the biological background to the development of ideas on rapid eye movement sleep (REM sleep), so-called paradoxical sleep (PS), and its relation to dreaming. Aspects of the phenomenon which are discussed include physiological changes and their anatomical location, the effects of total and selective sleep deprivation in the human and animal, and REM sleep behavior disorder, the latter with its clinical manifestations in the human. Although dreaming also occurs in other sleep phases (non-REM or NREM sleep), in the human, there is a contingent relation between REM sleep and dreaming. Thus, REM is taken as a marker for dreaming and as REM is distributed ubiquitously throughout the mammalian class, it is suggested that other mammals also dream. It is suggested that the overall function of REM sleep/dreaming is more important than the content of the individual dream; its function is to place the dreamer protagonist/observer on the topographical world. This has importance for the developing infant who needs to develop a sense of self and separateness from the world which it requires to navigate and from which it is separated for long periods in sleep. Dreaming may also serve to maintain a sense of 'I'ness or “self” in the adult, in whom a fragility of this faculty is revealed in neurological disorders.

Abstract: In recent years, the noninvasive monitoring of steroid hormone metabolites in feces of mammals and droppings of birds has become an increasingly popular technique. It offers several advantages and has been applied to a variety of species under various settings. However, using this technique to reliably assess an animal's adrenocortical activity is not that simple and straightforward to apply. Because clear differences regarding the metabolism and excretion of glucocorticoid metabolites (GCMs) exist, a careful validation for each species and sex investigated is obligatory. In this review, general analytical issues regarding sample storage, extraction procedures, and immunoassays are briefly discussed, but the main focus lies on experiments and recommendations addressing the validation of fecal GCM measurements in mammals and birds. The crucial importance of scrutinizing the physiological and biological validity of fecal GCM analyses in a given species is stressed. In particular, the relevance of the technique to detect biologically meaningful alterations in adrenocortical activity must be shown. Furthermore, significant effects of the animals' sex, the time of day, season, and different life history stages are discussed, bringing about the necessity to seriously consider possible sex differences as well as diurnal and seasonal variations. Thus, comprehensive information on the animals' biology and stress physiology should be carefully taken into account. Together with an extensive physiological and biological validation, this will ensure that the measurement of fecal GCMs can be used as a powerful tool to assess adrenocortical activity in diverse investigations on laboratory, companion, farm, zoo, and wild animals.

Abstract: Current emphasis on odorant physiochemical features as the basis for perception largely ignores the synthetic and experience-dependent nature of olfaction. Olfaction is synthetic, as mammals have only limited ability to identify elements within even simple odor mixtures. Furthermore, olfaction is experience-bound, as exposure alone can significantly affect the extent to which stimuli can be discriminated. We propose that early analytical processing of odors is inaccessible at the behavioral level and that all odors are initially encoded as `objects' in the piriform cortex. Moreover, we suggest that odor perception is wholly dependent on the integrity of this memory system and that its loss severely impairs normal perception.