title: Developmental changes in ultrasonic vocalizations by infant Japanese echolocating bats, Pipistrellus abramus.
abstract: Developmental changes in vocalizations by Pipistrellus abramus were investigated during the first post-natal month. Vocalizations by pups on the day of birth were frequency-modulated ultrasounds from 30.0 ± 4.0 kHz to 19.3 ± 1.9 kHz with multiple harmonics. The terminal frequency of the second harmonic (TF(2)) of pup vocalizations corresponded to that of the fundamental (TF(1)) in adult bats (41.4 ± 2.6 kHz), suggesting that pup vocalizations can be easily detected by the mother. In addition, there are two types of infant vocalization: short duration echolocation precursor and long duration isolation calls, which showed separate developmental patterns over time.
authors.affiliation: Faculty of Life and Medical Sciences, Bio-navigation Research Center, Doshisha University, Kyotanabe, 610-0321, Japan. shiryu@mail.doshisha.ac.jp
authors.forename: Shizuko
authors.initials: S
authors.lastname: Hiryu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Riquimaroux
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002685:Chiroptera / Q000254:growth & development*; D004455:Echolocation; D006309:Hearing; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013997:Time Factors; D014465:Ultrasonics; D014828:Vocalization, Animal