@article {57576, title = {Vocal Development of Horsfield{\textquoteright}s Leaf-Nosed Bat Pups (Hipposideros larvatus)}, year = {2019}, abstract = {

Bats are an appealing animal for investigating the biological basis and evolution of speech-related traits in wild mammal systems. We investigated vocal development in Horsfield\&$\#$39;s leaf-nosed bat pups, Hipposideros larvatus. We found that newborn bats emit many types of isolation calls, including downward frequency modulation (DFM), arched frequency modulation (AFM), upward frequency modulation (UFM), and others. The gradual decrease of Euclidean distance measurements revealed that pup isolation calls (DFM, AFM, UFM) gradually change into adult social calls. Furthermore, one of the isolation call types (UFM type) encoded an individual signature. By contrast, we report that early echolocation calls and isolation calls develop in parallel. As pups develop, early echolocation calls gradually mature and transform into adult-like echolocation calls. The interval and duration of echolocation calls decreases, while the peak frequency and bandwidth of frequency modulation increases.

}, keywords = {bats, echolocation calls, individual signature, isolation calls, vocal development}, doi = {10.3161/15081109ACC2019.21.1.016}, author = {Chi, Tingting and LIU, Muxun and Tan, Xiao and Li, Yu and Xiao, Yanhong and Sun, Keping and Jin, Longru and Feng, Jiang} } @article {53434, title = {Social vocalizations of big-footed myotis (Myotis macrodactylus) during foraging}, journal = {Integrative Zoology}, year = {2018}, month = {Feb-12-2020}, abstract = {

Acoustic signals play a crucial role in transmitting information and maintaining social stability in gregarious animals, especially in echolocating bats which rely primarily on biological sonar for navigating in the dark. In the context of foraging without relying on tactile, visual, or olfactory cues, acoustic signals convey information not only on food, but also on ownership and defense of resources. However, studies on such information remain fragmentary. In the present study, we aim to document the social vocal repertoire of Myotis macrodactylus at natural foraging sites. Multiple acoustic analyses and spectrographic classification revealed a rich foraging vocal repertoire comprising 6 simple syllables and 2 composites. Discriminant function analyses associated with a subset-validation procedure provided an optimal method to spectrographically classify all recorded sounds into different syllable types. Multidimensional scaling of median values of multiple parameters further confirmed notable differences among these syllables in a three-dimensional space. In addition, Euclidean distance analysis showed that there were some spectral similarities between specific social vocal syllables and feeding buzzes, which implied a potential jamming role. Altogether, the data indicate that bats at foraging sites under natural conditions used variant social vocalizations with different functions in addition to echolocation calls, providing supporting evidence for further work on the function and vocal mechanisms of acoustic communication in mammals.

}, keywords = {bats, foraging, Social calls, Spectro-temporal features}, doi = {10.1111/1749-4877.12367}, url = {http://doi.wiley.com/10.1111/1749-4877.12367}, author = {Guo, Dongge and Luo, Bo and Zhang, Kangkang and LIU, Muxun and Metzner, Walter and Liu, Ying and Feng, Jiang} }