Development and enemy recognition of the curve-billed thrasher Toxostoma curvirostre. Bulletin of the AMNH ; v. 78, article 2.
Supplemental Materials
Date
item.page.datecreated
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
DOI
DOI
Abstract
"Thrashers were studied in the wild and in captivity from hatching until about 90 to 96 days old. The physical development, and that of behavior, which appears typically passerine, are recorded. Experiments on enemy recognition were carried out. Such fundamental acts as self feeding and some responses to predators were not exhibited even on leaving the nest; after appearing, both these types of behavior were modified by experience. Enemies were not recognized as such; the thrashers responded to some non-enemies as to their enemies. These responses usually combined exploratory acts and fleeing acts, sometimes a display and once pugnacious activities. Which type was dominant, with the exception of the snake display, appeared to depend not only on the size of the object, its familiarity or otherwise, but also greatly on its activity in relation to the thrashers. Thrashers probably had to learn what not to fear. the snake display appeared to be a more stereotyped pattern of behavior than other responses to enemies. While large snakes elicited this response in maximum intensity, many other objects called it forth in less than maximum intensity. The snake display appeared to be elicited by a pattern of stimuli, and a wide variation in this weakened, without completely destroying it. The feeding response and exploratory pecking were also rather stereotyped in execution; but the stimulus objects which elicited them were very diversified. There was a tendency to actually swallow things within certain limits of size, taste and perhaps texture, but the tendency to peck and seize a wide variety of objects insured that when food objects were available, even though strange, they would be tried. The thrashers' responses to objects appeared to be the result of general tendencies to respond to a wide variety of stimuli. While many of the thrashers' activities had an innate basis, the stimulus conditions in which they were given were generalized. This provided the raw material with which experience worked to fit the thrashers' generalized behavior to its particular environment"--P. 242.
Description
Includes bibliographical references.