Page:American Journal of Psychology Volume 21.djvu/42

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32
PORTER

is a place to be hopped upon, but no further does the analysis go. Working on this place brings a pleasurable result, but there is no analysis. The keen rivalry and almost equal fighting ability, the change in the female Sparrow's condition of health and the food more to her liking were particularly suited to bring out some evidence of imitation. This evidence is of the same kind as that in series A and B and other evidence obtained later with the Crows and Orioles. There are some changes in the behavior of both the Junco and the Sparrow, changes from what we are pretty certain would have occurred if the other bird had not been present. These would point to imitation which might be called intelligent. That is, without first giving these birds previous experience with this box we could hardly expect the definite acts called forth in each by the other. There is much proof of the "following instinct."

Fig. 13

The female English Sparrow was ready to jump on the top string. The Junco was standing by uttering a series of plaintive notes. These two birds often fought each other for the position in front of the strings.

Series E.

Tests with the Junco of the Preceding Series, a White-throated Sparrow, a Field Sparrow, a male English Sparrow and a young Song Sparrow.[1]


  1. It is a duty both pleasantly and gladly performed to be able to acknowledge at this point the courtesy and unreservedness with which Mr. and Mrs. Worthington of the "Worthington Society for the Investigation of Bird Life" placed at the writer's service for purposes of investigation every facility not only as to birds and cages at the aviary