Bats resolve conflicting sensory information for individual recognition

• Published in: Current biology Vol. 35; no. 8; pp. 1883 - 1889.e3
• Main Authors: Knörnschild, Mirjam, Nagy, Martina, Russo, Danilo
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 21.04.2025
• Subjects: Animals; bats; Chiroptera - physiology; cognition; communication; distress calls; Female; individual recognition; individual signature; Male; playback; Recognition, Psychology; sensory conflict; Social Behavior; violation-of-expectation; Vocalization, Animal; vocalizations; bats; individual signature; cognition; vocalizations; playback; violation-of-expectation; sensory conflict; communication; distress calls; individual recognition
• ISSN: 0960-9822; 1879-0445; 1879-0445
• DOI: 10.1016/j.cub.2025.02.060

Recognizing conspecifics individually is paramount in shaping animal societies,1,2,3,4,5,6,7,8 and vocal signals can play an important role in this process.9,10,11,12 Humans13 and some other species14,15,16,17,18 identify individuals by integrating information from different sensory modalities. This ability can facilitate stable relationships, kin recognition, and cooperative interactions.5,6,7,8 Studies of individual recognition in wild animals remain rare.19,20,21 Here, we present experimental evidence that wild greater sac-winged bats, Saccopteryx bilineata, a species with stable social groups, high roost fidelity, and a preference for well-lit day-roosts,22,23 recognize individual group members. In many species,24,25,26,27,28,29 including bats,30,31,32,33,34 individuals produce distress calls when physically constrained by a predator. We show that distress calls of S. bilineata encode individual signatures. Further, we conducted playback experiments at the day-roosts to test for individual recognition. We used a violation-of-expectation paradigm in which the subject is presented with information for individual identification aligning or conflicting with one another.17 When individual recognition occurs, the subject may show heightened attention to conflicting information17,19,21 or the plausible association.18,35,36 Remarkably, roosting bats only approached the source of a distress call under plausible conditions—when the supposed caller was absent from the roost. When confronted with an impossibility—the supposed caller was in the roost and its voice simultaneously came from elsewhere—bats ignored the playback entirely. This striking ability to detect and reject such inconsistencies reveals a high level of cognitive sophistication, as these bats reconcile what they see or smell with what they hear to assess the reality of a situation. [Display omitted] •Bats recognize individual group members using vocal signatures in distress calls•Playback experiments show bats respond only to plausible distress call scenarios•Bats ignore distress call playbacks when conflicting sensory cues are presented•Greater sac-winged bats can reconcile sensory inputs and reject contradictions Knörnschild et al. reveal that greater sac-winged bats can detect inconsistencies in sensory information for individual recognition. Playback experiments show that bats ignore distress calls from visibly present roost mates but respond when those roost mates are absent, demonstrating a striking ability to reconcile what they hear with what they see or smell.