Document Type


Degree Name

Master of Science (MSc)




Faculty of Science

First Advisor

Not Applicable

Advisor Role

Not Applicable


In Experiment 1, pigeons were trained at a 1-s dark and a 1-s houselight illuminated delay interval to discriminate between sequences of two and four flashes of light (feeder illumination). These sequences could be discriminated on the basis of the number of flashes, the number of gaps, or the duration of the gap between flashes. A choose-few bias was obtained at extended dark delays, but no biased forgetting was observed at extended illuminated delays. The pigeons may have confused long dark delays with the longer gaps between flashes on few sample trials. In Experiment 2, additional sample sequences were included which controlled for the gap duration difference between few and many samples. A significant choose-many bias was obtained at extended dark delay intervals, with no biased forgetting found at extended illuminated delays. It appears that pigeons utilize multiple cues to discriminate sequences of light flashes. Experiment 3 had naive pigeons trained to discriminate center key light sequences to determine whether pecking behaviour produced greater control by number of flashes. No biased forgetting was observed during dark or illuminated delay intervals. It does not appear that pigeons rely on an event switch to count flashes, but utilize multiple features of a sequence to discriminate few from many light flashes.

Convocation Year


Convocation Season