This video is under embargo. Please login to access this video.
Caption
The adult male Squibbs is traveling ahead of a mother, Kutu, with her two offspring, subadult Kana and dependent infant Kathy. Squibbs sees the snake that is placed in the middle of a small path. He startles and then emits five alert hoos over 6 s. He diverts from the path, taking another route, and leaves. Kutu then arrives 12 s after Squibbs gave his final alert hoo and left. Within our classification, she and her daughter Kana are now receivers classed in the “heard” category, having arrived within 3 min of the last alert hoo. This means that she has most likely heard the alert hoo, but because Squibbs left before she arrived, she has not seen the exact position of the half-hidden, highly camouflaged snake. Kutu diverts off the path rather than approaching the snake. She rejoins the path after 10 m and continues her journey. She does not emit any vocalizations, and neither does her daughter, Kana (10 years old), arriving 2 s after her mother leaves. Kana looks toward the snake and then follows the same trajectory as her mother.
Credit
<I>Current Biology</I>, Crockford et al.: "Wild chimpanzees inform ignorant group members of danger."
Usage Restrictions
Videos are under embargo until Thursday, December 29th at 12 Noon ET.