Prenatal exposure to incubation calls affects song learning in the zebra finch

Abstract

Songbirds are important models for understanding the mechanisms and fitness consequences of imitative vocal learning. Although the effects of early-life environmental and social conditions on song learning are well-established, the impact of early sound exposure has received surprisingly little attention. Yet recent evidence hints at auditory sensitivity in songbird embryos, including in the zebra finch (Taeniopygia guttata), a classic model species for song learning. Here, we tested whether prenatal exposure to incubation calls—highly rhythmic parental vocalisations produced on the nest—affected song learning in zebra finches. Embryos were exposed in the egg to either incubation (treatment) or contact (control) calls, and after hatching were reared in a large colony. The playback treatment did not affect song complexity nor the accuracy of song copying from the social father, but instead increased learning of non-paternal song syllables. This, in turn, improved males’ mounting success in mating trials. These effects may be attributable to changes in juvenile social behaviours, as playback also influenced male behaviour during mating trials. Our study provides the first experimental evidence that prenatal acoustic environment affects song learning and courtship behaviour in songbirds, thereby raising interesting questions on the role of innate versus acquired biases for vocal learning.

Song Feature Specific Analysis of Isolate Song Reveals Interspecific Variation in Learned Components

“…Since non‐adult social interaction (West and King, ; Fehér et al , ) and pre‐hatching auditory experience (Katsis et al ., ) have been identified to play a role in avian vocal development, the effects of rearing condition on scores were analyzed. No significant effect of isolate rearing condition was found for syllable morphology (LM, highest f = 2.9 for heterospecific group), rhythm (highest f = 2.5 again for heterospecific group), or syntax (highest f = 1.2 for pair in masking noise).…”

Breeding ecology of the Yellow-bellied Warbler (Abroscopus superciliaris)

“…The parent may modify its incubating behavior according to the development of the egg embryo. Several studies have documented parentembryo communication in birds (Colombelli-Négrel et al 2012;Mariette and Buhanan 2016;Katsis et al 2018;Mariette et al 2018). It is possible that A. superciliaris parents can either perceive the progress of embryo development or communicate with the embryo to achieve synchronism.…”

Adult‐like neural representation of species‐specific songs in the auditory forebrain of zebra finch nestlings

“…Hearing sensitivity is not adult‐like until around 20 dph (Amin et al., 2007; Brittan‐Powell & Dooling, 2004), habituation rates change across development (Miller‐Sims & Bottjer, 2014; Stripling et al., 2001), ZENK expression in auditory regions is not selective for conspecific song until 30 dph (Jin & Clayton, 1997; Stripling et al., 2001), and individuals do not memorize songs, for production or during operant conditioning, before the sensitive period opens at ~25 dph (Braaten, 2010; Roper & Zann, 2006). However, there are a growing number of studies indicating that prenatal acoustic experience can have postnatal effects (Katsis et al., 2018; Mariette & Buchanan, 2016) and that embryos and nestlings already have the ability to habituate to and discriminate among specific songs (current study; Colombelli‐Négrel et al., 2014; Kleindorfer et al., 2018) and even to learn and produce certain call elements (Colombelli‐Négrel et al., 2012; Langmore et al., 2008; Madden & Davies, 2006). For example, cross‐fostered superb fairy‐wren chick begging calls closely match the incubation calls of their foster mothers at hatching, presumably as a mechanism to detect unsimilar brood parasitic chicks (Colombelli‐Négrel et al., 2012).…”