Clever Corvids: no! parrots inventing a tool to reach food (Introduction)

by David Turell , Thursday, November 08, 2018, 23:50 (2207 days ago) @ David Turell

Cockatoos can make and use tools to reach food:

https://www.sciencedaily.com/releases/2018/11/181107172905.htm

"The Goffin's cockatoo (Cacatua goffiniana) is a type of parrot. Captive Goffins are capable of inventing and manipulating tools, even though they aren't known to use tools habitually. The authors of the present study investigated two questions: do Goffins adjust tool properties to save effort, and if so, how accurately can they adjust tool dimensions for the task? The authors supplied six adult cockatoos with large cardboard sheets to tear into strips as tools for the testing apparatus: a food platform with a food reward set at varying distances (4-16cm) behind a small opening which also varied in width (1-2cm).

"They found that the Goffins were capable of adjusting the length of their cardboard strip tools to account for variations in food distance, making shorter tools when the reward was closer than when it was set farther away. In every case, if a first-attempt tool was too short, the second-attempt tool would be significantly longer. On average, all six birds made significantly longer tools than were required to reach the reward in all test conditions, with the birds tending to make increasingly long tools as the study progressed -- perhaps as a risk-avoidance strategy.

"However, only one bird was able to make a sufficiently-narrow tool to successfully reach the food reward when the opening was at its narrowest. The authors hypothesize that the shearing technique the birds use to tear the cardboard limits the narrowness of the resulting strips.

"Alice Auersperg adds: "The way they inserted and discarded manufactured pieces of specific lengths differently depending on condition suggests that the cockatoos could indeed adjust their tool making behavior in the predicted direction but with some limits in accuracy.' "

Comment: Another bird brain is shown to solve simple problems