Goffin cockatoos wait for qualitative and quantitative gains but prefer 'better' to 'more'

Abstract

Evidence for flexible impulse control over food consumption is rare in non-human animals. So far, only primates and corvids have been shown to be able to fully inhibit the consumption of a desirable food item in anticipation for a gain in quality or quantity longer than a minute. We tested Goffin cockatoos (Cacatua goffini) in an exchange task. Subjects were able to bridge delays of up to 80 s for a preferred food quality and up to 20 s for a higher quantity, providing the first evidence for temporal discounting in birds that do not cache food.

Figure 1.

Mean percentage of successful exchanges in the DQL, for 2–80 s delays, for the two test and the two control conditions. Black bars represent test 1: pecan for most preferred; light grey bars represent test 2: pecan for second/least preferred; white bars represent control 1: cashew for meat and dark grey bars represents control 2: cashew for pecan.

Figure 2.

Mean percentage of successful exchanges in the DQN, for 2–20 s delays, for the two test (white, 1 : 2; black, 1 : 6) and the two control (dark grey, 2 : 1; light grey, 6 : 1) conditions.