Biology subjects

Knörnschild, M.

Publications and source records attributed to Knörnschild, M..

4 recordsLinked to original sources

bioRxiv2025

Cooperative Behaviors and Social Interactions in the Carnivorous Bat Vampyrum spectrum

Bats exhibit a diverse array of social behaviors, yet detailed studies on the intricacies of these interactions, particularly in rare species like the spectral bat (Vampyrum spectrum), remain scarce. This study presents the first comprehensive description of prey sharing and other social behaviors in a wild social group of V. spectrum. Over several months, we conducted extensive video recordings in a hollow tree, used as a day- and night-roost, to document these behaviors, aiming to elucidate key social interactions among the bats and their role within their ecological niche. We observed various remarkable social behaviors, including food sharing between family members. Our findings support the hypothesis that prey sharing as a form of biparental care may serve as a method for adults to transition young bats from milk to a carnivorous diet, ensuring adequate food intake and allowing them to practice how to handle large prey items. We also challenge the notion that V. spectrum forages exclusively solitarily, as we documented several instances of synchronized roost departures and returns and thus presumably cooperative foraging. This indicates a more complex social structure and behavioral ecology than previously understood. Our comprehensive analysis of observational data enhances our understanding of the social dynamics of V. spectrum, providing new insights into the evolution of cooperative behaviors in bats. HighlightsExtensive parental care: Most likely both male and female spectral bats participate in parental care, e.g. food provisioning, a rare behavior among mammals Prey sharing as a social cooperative behavior: Detailed observations of prey sharing within the roost, highlighting social cooperation and resource allocation Extended dependency period for pups: A prolonged developmental period allows pups to receive care and acquire essential survival skills until they achieve full independence Juvenile play: Pups engaged predominantly in social play (mock fights), but also played with objects or food items, a rare behavior among bats

animal behavior and cognition↗

bioRxiv2025

Do it yourself: Creating 3D brain-surface models and custom-made brain matrices for guided sectioning using photogrammetry and three-dimensional printing technology

Neuroethologists study many non-model animals. The development of techniques for precise and standardized histological brain analysis is key for understanding neural mechanisms across species. Here we present a novel cost-effective approach combining photogrammetry and three-dimensional printing technology to generate 3D brain surface models and produce species-specific brain matrices for precise and reproducible trimming, blocking, and sectioning of brain tissue. Using this strategy, we generated the first 3D brain surface model and brain matrix for Sebas short-tailed fruit bat Carollia perspicillata, CP. We generated the 3D brain surface model with the open-source 3D graphics suite Blender and its inexpensive photogrammetry plug-in Snapmesh. High-quality photographs of two male CP brains were used for the 3D-reconstruction, resulting in a 3D surface model. Photogrammetry thus offers a viable, cheap alternative to techniques otherwise requiring access to costly 3D- or CT-scanners. The brain matrix was then modeled using Blender, and printed using a 3D printer. Our brain matrix facilitates and standardizes trimming or blocking of brains, providing consistent access to brain regions of CP in the sagittal and coronal planes. Using this workflow, brain surface models and brain matrices can be produced from brains without tissue loss. Our approach provides an affordable, and tissue-preserving alternative for the generation of 3D brain surface models and brain matrices and will benefit researchers globally, especially those with limited funding, no access to scanners or working with particularly valuable specimen.

neuroscience↗

bioRxiv2024

Maternal behavior influences vocal practice and learning processes in the greater sac-winged bat

Learning, particularly vocal learning, is often a social process. In human infants, it is well-established that social interactions influence speech acquisition and are hypothesized to modulate attentiveness and sensory processes, thereby affecting the speech-learning process. However, our understanding of how social interactions shape vocal ontogenetic processes in non-human mammals, particularly those which vocally learn, remains limited. In the bat Saccopteryx bilineata, pups acquire the adult vocal repertoire through a distinctive babbling behavior that shows interesting similarities to human infant babbling. While babbling encompasses many different syllable types, it is particularly noteworthy that pups learn song syllables by imitating adult singing males. The pups social environment involves frequent interactions with their mothers, whereas adult males mainly serve as the primary source of acoustic input. We monitored the vocal ontogeny of wild pups, investigating whether their social environment influenced three aspects of babbling: the amount of vocal practice, the pups final syllable repertoire size and the production of the syllable types acquired through vocal learning. The results demonstrate that maternal behavioral displays significantly influence the amount of vocal practice, the presence and versatility of song syllable types in babbling and the percentage of mature song syllables. Our findings show that maternal feedback plays a significant role in the vocal ontogeny and learning processes of S. bilineata, thus enhancing our understanding of the relationship between social feedback and vocal development in mammalian vocal learners.

animal behavior and cognition↗

bioRxiv2021

Social behaviour and vocalizations of the tent-roosting Honduran White Bat

Bats are highly gregarious animals, displaying a large spectrum of social systems with different organizational structures. One important factor shaping sociality is group stability. To maintain group cohesion and stability, bats often rely on social vocal communication. The Honduran white bat, Ectophylla alba exhibits an unusual social structure compared to other tent-roosting species. This small white-furred bat lives in perennial stable mixed-sex groups. Tent construction requires several individuals and, as the only tent roosting species so far, involves both sexes. The bats social system and ecology render this species an interesting candidate to study social behaviour and social vocal communication. In our study, we investigated the social behaviour and vocalizations of E. alba in the tent by observing two stable groups, including pups, in the wild. We documented 16 different behaviours, among others, play and fur chewing, a behaviour presumably used for scent-marking. Moreover, we found 10 distinct social call types in addition to echolocation calls, and, for seven call types, we were able to identify the corresponding behavioural context. Most of the social call types were affiliative, including two types of contact calls, maternal directives, pup isolation calls and a call type related to the fur-chewing behaviour. In sum, this study entails an ethogram and describes the first vocal repertoire of a tent-roosting phyllostomid bat, providing the basis for further in-depth studies about the sociality and vocal communication in E. alba.

animal behavior and cognition↗