On the third day of life, four groups of eight chicks each were given either rape or canary seed, exclusively. The following day the chicks were given the seed they had not experienced the day previously. For eight days subsequently, the chicks were offered both seeds and the proportion by weight of each seed eaten was determined. Chicks initially fed canary seed showed a strong preference for canary when both seeds were first offered and the chicks initially fed rape seed showed no clear preference. As the days on both foods progressed, the preferences of both groups shifted toward rape seed, although group differences in favor of the food first fed existed throughout the testing period. © 1969, Psychonomic Journals, Inc.. All rights reserved.
