ABS 2022
Babbling in bat pups and human infants: shared features of an extraordinary vocal practice behavior
Ahana A. Fernandez1, Mirjam Knörnschild1,2,3. 1Museum für Naturkunde Berlin, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Berlin, Germany; 2Free University of Berlin, Berlin, Berlin, Germany; 3Smithsonian Tropical Research Institute, Panama City, Panama, Panama

Speech is the vocal motor output aspect of language and requires precise control over our vocal apparatus, steered by neuronal mechanisms.  Every child needs to acquire this control to produce mature speech sounds (e.g. „ba“, „ga“). This process is observed during babbling, a production milestone in infant speech development, characterized by universal features.
Babbling is rare in non-human animals and so far, there is only one other vocal production learning (VPL) mammal besides humans that shows this behavior during ontogeny: the greater sac-winged bat Saccopteryx bilineata. We studied the entire vocal ontogeny of 20 wild pups to investigate whether babbling in S. bilineata pups is characterized by the same features that define infant babbling. Our results showed that the features defining human infant babbling are also characteristic of pup babbling, including conspicuous features like rhythmicity and syllable reduplication. The similarities in babbling features between two species sharing traits such as VPL, laryngeal sound production and similar brain architecture are a promising basis for comparative investigations of neuronal substrates in mammalian VPL.