Failure to replicate the 'work ethic" effect in pigeons.
We report six unsuccessful attempts to replicate the "work ethic" phenomenon reported by Clement, Feltus, Kaiser, and Zentall (2000). In Experiments 1-5, pigeons learned two simultaneous discriminations in which the S+ and S- stimuli were obtained by pecking an initial stimulus once or multiple (20 or 40) times. Subsequent preference tests between the S+ stimuli and between the S- stimuli mostly revealed indifference, on average, between the S+ from the multiple-peck (high-effort) trials and the S+ from the one-peck (low-effort) trials, and likewise between the two respective Sstimuli. Using a slightly different procedure that permitted assessment of the relative aversiveness of low versus high effort, Experiment 6 again revealed a pattern of indifference despite showing that pigeons took considerably longer to begin pecking on high- than on low-effort trials. Our findings call into question the reliability of the original findings and the sufficiency of the hypothesized within-trial contrast mechanism to produce them.
Vasconcelos
Marco
M
Department of Psychological Sciences, Purdue University, 703 Third Street, West Lafayette, IN 47907-2081, USA. marcov@psych.purdue.edu
Urcuioli
Peter J
PJ
Lionello-DeNolf
Karen M
KM
D000818:Animals; D001522:Behavior, Animal; D002755:Choice Behavior; D010856:Columbidae; D004193:Discrimination Learning; D005247:Feeding Behavior