Chimps chat, just like we do—and like many of us, they spend a lot of time gabbing about what they want to eat and where they're going to get their next meal, Discovery reports. For a study published in Animal Behaviour, scientists camped out in the Ivory Coast's Tai Forest for more than 750 hours to observe these great apes and found that they make a particular sound when they're foraging for snacks, but that their voices change even more so when they're on a quest for a certain fruit—and find trees of a certain size that have it. "Chimpanzees definitely have a very complex communication system that includes a variety of vocalizations, but also facial expressions and gestures," project leader Ammie Kalan tells Discovery. The vocalization that stood out quite prominently during the study: high-pitched calls when they found fruit from Nauclea trees.
Kalan explains this fruit boasts a high energy content, is "big and easy to ingest," and smells "very good in the forest." The nine adult chimps that were under observation exhibited "food calls of a higher dominant and peak frequency" when they stumbled across the much-coveted Nauclea treats, BioScholar reports. The chimps altered their pitch even further depending on tree size: Smaller trees got a high-pitched call, but larger trees with more bounty elicited lower-pitched calls, attracting more chimps, according to the study's highlights listed on ScienceDirect. The researchers do note, however, that more study is needed to see if the food calls were specific to this group of chimps, as well as whether similar vocalizations are used for other types of food, per BioScholar. (Maybe all that Nauclea fruit helps chimps rule at video games.)