Goffin's cockatoos, a kind of small parrot native to Australasia, have been shown to have similar shape-recognition abilities to a human two-year-old. Though not known to use tools in the wild, the birds have proved skilful at tool use while kept in the cage. In a recent experiment, cockatoos were presented with a box with a nut inside it. The clear front of the box had a "keyhole" in a geometric shape, and the birds were given five differently shaped "keys" to choese from. Inserting the correct "key" would let out the nut.
戈芬的凤头鹦鹉是一种原产于澳大拉西亚的小鹦鹉，它的形状识别能力相当于两岁儿童。尽管野外的这些鸟不知道使用工具，但事实证明，在笼中长大的可以熟练使用。最近的一次实验中，给凤头鹦鹉一个盒子，盒子里有一颗坚果。盒子正面有一个几何形状的“钥匙孔”，给这些鸟五个不同形状的“钥匙”让它们从中选择。插入正确的“钥匙”坚果会掉出来。
In humans, babies can put a round shape in a round hole from around one year of age, but it will be another year before they are able to do the same with less symmetrical shapes. This ability to recognize that a shape will need to be turned in a specific direction before it will fit is called an "allocentric frame of reference". In the experiment, Goffin's cockatoos were able to select the right tool for the job, in most cases, by visual recognition alone. Where trial-and-error was used, the cockatoos did better than monkeys in similar tests. This indicates that Goffin's cockatoos do indeed possess an allocentric frame of reference when moving objects in space, similar to two-year-old babies.
人类的婴儿大约一岁左右就可以在圆孔中放入圆形物品，但要想在对称性较差的情况下也能做到这一点，还需要一年的时间。这种能够识别形状需要朝特定方向转动才能匹配的能力被称为“异中心参照系”。在实验中，戈芬的凤头鹦鹉能够在大多数情况下仅通过视觉识别来选择合适的工具。经过反复试验，类似的测试中，凤头鹦鹉比猴子表现更好。这表明，当在空中移动物体时，戈芬的凤头鹦鹉确实具有异中心参照系，类似于两岁的婴儿。
The next step, according to the researchers, is to try and work out whether the cockatoos rely entirely on visual clues, or also use a sense of touch in making their shape selections.
根据研究人员的说法，下一步是尝试确定凤头鹦鹉是完全依赖视觉线索，还是在选择形状时也使用触觉。