Imprinting to a Static Feature of the Home Environment

Abstract

IN 1951 Ramsay¹ reported observations which suggest that recognition of the home environment by precocial birds might be regarded as a form of imprinting. This view was also expressed by Thorpe² and implies that imprinting can occur not only to a fluctuating stimulus but also to any salient feature of the natural environment. The occurrence of attachment to a stationary object has since been demonstrated, though not beyond controversy, by Hess³, Gray⁴, and Abercrombie and James⁵. Both Hess and Gray used as stimuli a black circle and a black triangle of comparable size. Young domestic chicks were exposed to one or the other of these figures for one day, having previously been reared in visual isolation; when later tested in a choice apparatus with the figures at opposite ends they showed a clear preference, in terms of approach behaviour, for the original over the new object. Abercrombie and James tested their chicks in a runway at each end of which was a continuous light, one of them being accompanied by a stationary polythene ball which served as a ‘lure’. They found that in this situation chicks eventually formed an attachment to the lure, although they required more trials for its formation than did others which had been trained with the lure accompanied by a flickering light.