Douglas K. Candland

Dominance status and adrenocortical reactivity to stress in squirrel monkeys (Saimiri sciureus)

Squirrel monkeys (Saimiri sciureus, Iquitos) were exposed to a sequence of three stresses: A live snake, ether anesthesia, and physical restraint. Plasma cortisol concentrations were determined both following each stress exposure and before and after the sequence of stresses. Dominant males demonstrated lower unstressed plasma cortisol levels than subordinates. Although the form of the relationship between adrenal activity and social dominance differs for the types of stress, dominant animals always show the greatest adrenal reactivity to stress.

THE OPEN FIELD: SOME COMPARATIVE DATA*

This paper is primarily concerned with two attributes of the open-field test of emotionality. The first concerns the generality of the behavior patterns elicited by the open-field to animals of different species and ages. The second is concerned with how the two most commonly used indices of emotionality, activity and defecation, correspond to change in heart rate, a physiological measure sometimes proposed as an indicator of emotionality. Both attributes are important if one questions the validity and reliability of the open-field test as a general measure of emotionality in a variety of animals. It is likely that the behaviors elicited by the open-field vary according to the species tested, since species probably differ in the display of their characteristic syndromes of emotionality. This paper reports comparisons of open-field behavior elicited from several disparate species.

Endocrine effects of grouping and dominance rank in squirrel monkeys

Abstract Urinary 17-hydroxycorticosteroids (17-OHCS), total catecholamines and 17-ketosteroids (17-KS) were determined for two groups of squirrel monkeys. One group had been colonized for four years and the other group had lived in isolation for three years. Compared to the isolated animals, the colonized monkeys showed elevated 17-OHCS but unchanged catecholamine and 17-KS levels. In the colonized group the dominant animals had the highest 17-OHCS levels and the lowest catecholamine levels, while the subordinate animals showed lower 17-OHCS levels and elevated catecholamine levels. 17-KS levels were related to dominance rank by a J-shaped function. The data are interpreted as showing that high levels of adrenocortical output are necessary for the maintenance of the group of behaviors that result in a high position in the dominance order. It is suggested that the results of this study on primates were contrary to the results of most studies on rodentia because these orders use different behavioral methods to determine dominance relationships.

Social Structure of the Squirrel Monkey (Saimiri sciureus, Iquitos): Relationships among Behavior, Heartrate, and Physical Distance

The relationships between heartrate, behavior, and physical distance were assessed in squirrel monkeys forming a stable colony. For many specific behaviors, heartrate is elevated from baseline 2 min b

Baboon (Papio hamadryas) visual preferences for regions of the face.

Preferences for regions of the face were examined in four members of a hamadryas baboon (Papio hamadryas) group. Subjects were presented a series of photographic slides displaying various facial regions and combinations of regions of the dominant male in the group with the use of the method of paired comparison. An apparatus consisting of a two-slide screen/two-push-button arrangement permitted the baboons to control slide selection and viewing duration. Both duration and frequency of slide activation were recorded. Correlations of viewing durations among all subjects were significant (p less than or equal to .05). The eye region alone and in combination with other regions received significantly more attention than did all other regions or combinations. Frequency measures were not significant. The results support findings obtained with rhesus monkeys (Macaca mulatta) and suggest that the eye region may provide a primate with an important source of information, possibly information about intent.

Reliability of the emotions profile index, primate form, withPapio hamadryas, Macaca fuscata, and twoSaimiri species

An evaluation of the reliability of the Emotions Profile Index (EPI), primate form, was carried out using two captive species of Old World monkeys (Papio hamadryas andMacaca fuscata) and two species (?) of New World monkeys (Saimiri sciureus andS. boliviensis). Observers, some familiar with the animals and some unfamiliar, rated members of the four groups at different times. Inter-rater reliability was high for most members of all species, but only when the observers were familiar with the animals. Assessments remained stable over at least one year.

A Model of Agonistic Behavior: Endocrine and Autonomic Correlates

Attempts to relate agonistic behavior to fluctuations in a specific physiological system, especially the autonomic nervous system, have been more instructive than conclusive in establishing the relationship between physiological functioning and aggression. Clearly, the variety of behaviors we label agonistic or aggressive are not the product of the functioning of a single, known system. If we were to select promising candidates, we might be well served to choose autonomic and endocrine functioning. Seeking physiological correlates of aggression in the endocrine system presents technical problems. Endocrine responses are not discrete, and the factors which control the nature and quantity of endocrine secretions are not completely understood. The endocrine system is composed of complex feedback subsystems, a characteristic which presents problems in deciding how and when to interrupt the sequences for measurement and investigation. These problems encourage unwanted disparity among studies and present difficulties in interpretation.

Urine as a communicator in a New World primate,Saimiri sciureus

New World primates face problems of communication distinct from those of their Old World counterparts. We suspected that the odor of urine might serve the function of communicating information among animals or troops. Two studies were conducted withSaimiri sciureus; one examined, in a laboratory enclosure, the influence of breeding season, social condition, area, and whether the urine was from known animals or from strangers, and the second measured, in a seminatural rain forest, responses to our spreadingSaimiri urine on selected sites. Enclosure and field produce the same general patterns of frequencies of behavior for urination, the urine wash and kick wash, and rubbing. The chief difference in behavior between the environments is found in the frequency of sneezing. Season (breeding or nonbreeding) is the most effective variable producing this general pattern: During the breeding season, males urine-wash throughout the enclosure or troop range, whereas during the nonbreeding season, this behavior is restricted in location, at least in the enclosure. At this time, females increase their frequencies of sniffing and rubbing. Many of these behaviors are observed only in special locations of the enclosure. The results show thatSaimiri respond differently to the urine of known and foreign animals, depending upon the season and whether they are with members of their own sex or both sexes. It is suggested that primates not equipped with specialized organs for scent marking may use urine opportunistically to communicate.

Videotape as a replacement for the human observer in studies of nonhuman primate behavior

Bucknell University, Lewisburg, Pennsylvania 17837 For both field and laboratory studies of animal behavior, the availability of portable videotape recorders permits both improved techniques of observation and a means for permanent storage and rapid retrieval of observations. In some circumstances, videotape may be used to replace a human O. Evidence is presented that the behavior of at least one nonhuman primate commonly used in behavioral research, the squirrel monkey, differs when a human 0 is present from when behavior is recorded solely by videotape, even after 3 years of daily contact with human beings.

Parameters affecting adaptation to and retention of open-field elimination in the rat ☆ ☆☆

Abstract In Experiment 1, rats descended from Car-worth Farms CFE strain, of 23, 40 and 70 days of age, were tested either weekly or twice daily in an open field. Massed tests (twice daily) required more trials to adapt than distributed (weekly) trials, although distributed Ss required longer, in terms of total time, to adapt. The younger the S, the more trials required to adapt. Retention tests 150 and 225 days following adaptation suggested that Ss which adapt most rapidly show greater emotionality as measured by number of boluses in the retention tests. Accordingly, Experiment 2 used rats of 23, 40 or 70 days of age and gave these Ss either 20, 40 or 60 open field tests. Retention was measured after 150 and 225 days. The results show that the fewer the number of trials, the more emotional the animal at retention. It is suggested that retention of emotional behaviour in the rat is a function of both constitutional factors and experiential factors.