Biology subjects

Mircheva, M.

Publications and source records attributed to Mircheva, M..

3 recordsLinked to original sources

bioRxiv2026

Who says what when? Patterns in captive common marmoset (Callithrix jacchus) volubility

Volubility - the number of vocalizations per unit of time - is an understudied aspect of animal communication, potentially crucial in cooperatively breeding species that depend on coordinated behavior. Callitrichid monkeys such as common marmosets (Callithrix jacchus) are often characterized as highly vocal, yet variation in their calling rates remains poorly quantified. We recorded 69,538 vocalizations from 45 captive marmosets tested in dyads across six experimental conditions. Total call rates varied with condition but not with caller sex or status. Alertness call production depended on caller status: breeders showed context-appropriate responses to an ambiguous object, whereas helpers responded more generally. Food calls were tightly coupled to feeding rather than food availability, with males calling more than females. Dyadic analyses revealed call-type-specific covariation between subjects and partners, consistent with vocal contagion for alertness calls and recruitment for food calls. These patterns indicate flexible, call-type-specific volubility and information sharing beyond simple arousal contagion.

animal behavior and cognition↗

bioRxiv2026

Identity-resolved vocal exchanges in multi-marmoset settings

Acoustic communication is tightly coupled to collective behaviour and social network structure in many animal societies. Yet continuous, identity-resolved recordings of multiple concurrent signalers are challenging. We evaluated a commercial acoustic camera for marmoset (Callithrix jacchus) vocal behavior across controlled bench tests and naturalistic family interactions. Spectral characterization showed the system is closest to neutral and most sensitive in 5-10 kHz, supporting reliable detection without correction in this range. Static localization accuracy was between 1-3 cm across the experimental enclosure. In simultaneous two-source tests, separation depended strongly on geometry and intensity level: very small spacing (20 cm) produced a single merged hotspot, frame-wise co-representation of multiple sources was infrequent and biased by sub-decibel level asymmetries. In natural 15-min family recordings (N=519 calls), the camera detected 96.5% of calls, among detected events, caller assignment was 97.6% correct (overall 94.2%). Ground-truth playback confirmed near-ceiling detection ([~]100%) and high assignment with two emitters ([~]98%), with reduced attribution in crowded four-emitter layouts. Together, these results indicate that acoustic imaging can deliver high detection and accurate caller attribution for typical marmoset vocalizations, with primary limitations arising from spatial crowding and small inter-source level differences. Importantly, this limitation can be mitigated in the native software by sequentially silencing suspected sound sources. The approach thus provides a practical and reliable path toward continuous, identity-resolved vocal monitoring in freely behaving primates.

animal behavior and cognition↗

bioRxiv2025

Common marmosets (Callithrix jacchus) do not differentiate between familiar and unfamiliar conspecifics based on pitch contour information

Previous studies suggest that vocal-learning species use variations of prosodic cues, such as changes in pitch, amplitude, or duration, in the conveying of meaning and emotions as well as individual recognition. Although it is known that the long-distance contact calls ("phee" calls) of common marmosets, a vocal non-learner, vary in prosodic information depending on individual characteristics, evidence of the species use of this information only recently started to emerge. In this study we tested 18 captive common marmosets (Callithrix jacchus) reactions to playbacks of familiar and unfamiliar individuals phee calls and extracted pitch-contour information. The playbacks consisted of i) natural phee calls from group members or unfamiliar conspecifics, or ii) synthesized pitch contours of familiar or unfamiliar phee calls following a natural or artificial syllable order as well as pure tones of similar frequency and duration. We found that although individuals seemed to show different reactions towards the natural calls of familiar and unfamiliar individuals, we did not find group level differences. Marmosets furthermore show significantly reduced interest in synthesized pitch contours compared to natural phee calls and did not differentiate between pitch contour playbacks and pure tone control stimuli, indicating that they did not categorize the pitch contours as conspecific calls. Our results suggest that extracted pitch contour information alone is not sufficient for marmosets to recognise conspecifics, however further studies are required to investigate the exact mechanism of individual recognition in marmosets.

animal behavior and cognition↗