Arousal and temporal factors in imprinting in mallards

Abstract

A number of factors affecting the learning processes in laboratory imprinting were examined. Two factors alone explain the degree to which young ducklings learn the characteristics of a given model: the length of exposure to the model, and the endogenous arousal state of the duckling. A third, the effect of muscular exertion is not warranted.The characteristics of some models are more rapidly learned than others, and the significance of this fact for biochemical studies of learning is discussed. In this study ease of learning coincided with innate preference: this suggests the presence of a neural filtering mechanism in the duckling which alters the assimilation of information into the CNS and hence controls both innate preference and lcarnability.The distinctive early writings of Lorenz (1935) provided a clear empirical and theoretical framework for subsequent research on imprinting (see reviews by Bateson, 1966; Mess, 1973; Sluckin, 1964;Smith, 1969). In the imprinting context the learning processes leading to filial attachment in the naive young nidifugous bird occur very rapidly. Knowing how rapidly an attachment to a model is formed is important for evaluating physiological and biochemical studies on the imprinting process. For example, one major criticism of the studies on brain ribonucleic acid (RNA) and protein synthesis during imprinting (Bateson, Horn, & Rose, 1972;Gervai & Csanyi, 1973; Smith. Nott, & Yarwood, 1970) is that the so-called biochemical correlates of learning obtained in these studies require a much longer exposure to the model than is required for obtaining consistent behavioral evidence of learning. The present parametric study of imprinting was designed t o explore a number of behavioral factors relevant to the interpretation and planning of physiological studies of imprinting. It defines an important nonspecific endogenous factor (termed arousal) which has implications for Iless's Law of Effort (1 959). MethodA total of 80 mallard ducklings (Anus platyrhynchos) were used in this experiment. These were selected from approximately twice that number in that ducklings which failed

Sexual imprinting as a two-stage process: mechanisms of information storage and stabilization

“…The corticosterone level in this situation would then probably be indicative of the fear induced in the birds by the exposure to the non-familiar object (e.g. Martin & Schutz 1975).…”

Stability of preference for odors after short‐term exposure in young spiny mice

“…increase in the level of arousal is important in imprinting in birds (Fischer, 1970;Kovach, 1970;Martin & Schutz, 1974). The pattern of response to both experimental odors was very similar.…”

Effects of Androgens and Oestrogens on the Behaviour of Chicks in an Imprinting Situation

“…The behavioural differences observed during the choice test thus probably result from unlearned preferences for one model as they already occurred during the first encounters between models and chicks. Such preferences have already been demonstrated: MARTIN and SCHUTZ (1975) for example showed that young mallard ducklings are more likely to follow and to imprint on a , blue ball than on a red cube. Detailed studies of the chicks' preferences have also been published (e.g.…”