File:Associative-Mechanisms-Allow-for-Social-Learning-and-Cultural-Transmission-of-String-Pulling-in-an-pbio.1002564.s011.ogv

English: Test of stimulus enhancement. Footage shows an observer bumblebee tested with the string task after the observation phase. Whilst the strings protruded in the normal region during in the observation, they protruded in two alternative regions during the test. For a few times, the bee lands on top of the left and right tables and tries to obtain the sucrose solution. After 50 s, the bee lands on the opposite side of the right table, tries to reach under the table, moves the string with her middle legs, moves the flower a little closer, and flies away. Then the bee lands several times on the table tops. After 3 min and 40 s, she lands on the left table, walks to the edge where the string protrudes, and subsequently leaves the table. Then, she manipulates and grasps the string with all her legs, gets her body around the string in an inverted position, and pulls the flower a little closer to the edge. Finally, she stays in an inverted position with her body under the string, grasping the string with all her legs, and extends her proboscis towards the edge and under the table.