Comparative cognition in three understudied ungulate species: European bison, forest buffalos and giraffes

A silent box could mislead a giraffe looking for carrots. Shake a box containing food and a giraffe may choose it correctly. Shake an empty box instead, and choosing it becomes a mistake. That small change helps distinguish understanding where a sound comes from from simply following an interesting movement.

Álvaro L. Caicoya, Federica Amici, Conrad Ensenyat and Montserrat Colell compared five European bison and five forest buffalo at Barcelona Zoo with six giraffes previously tested in Barcelona and Leipzig. The animals chose between containers after seeing food hidden, waiting thirty or sixty seconds, or watching one closed box being shaken. A separate condition checked whether they could locate food by smell alone.

The giraffes performed best overall, ahead of bison and then buffalo, but consistently favoured the shaken box whether it rattled or stayed silent. Their apparent success with a noisy box therefore did not establish that they understood its sound. Small captive samples also prevent turning the overall ranking into a general intelligence hierarchy. The revealing result is more specific: the very movement that directed these giraffes towards food could also direct them away from it.