Northern elephant seal harems (Mirounga angustirostris) are a cacophony of noises with males vocalizing at each other and occasionally getting into physical battles; what information is coded within those noises? Researchers at University of California, Santa Cruz used playback experiments (i.e. recording vocalizations and then playing the vocalizations back to other individuals) to discover that male northern elephant seals learn the unique vocalizations of their rivals to determine whether they should confront an opponent or relinquish based on previous interactions.
Sketch and fact contributed by Karli Chudeau
Source: Casey, C., Charrier, I., Mathevon, N., & Reichmuth, C. (2015). Rival assessment among northern elephant seals: Evidence of associative learning during male–male contests. Royal Society Open Scence, 2, 150228, DOI: 10.1098/rsos.150228.