Dynamics of crowing development in the domestic Japanese quail (Coturnix coturnix japonica)

Abstract

Species-specific behaviours gradually emerge, via incomplete patterns, to the final complete adult form. A classical example is birdsong, a learned behaviour ideally suited for studying the neural and molecular substrates of vocal learning. Young songbirds gradually transform primitive unstructured vocalizations (subsong, akin to human babbling) into complex, stereotyped sequences of syllables that constitute adult song. In comparison with birdsong, territorial and mating calls of vocal non-learner species are thought to exhibit little change during development. We revisited this issue using the crowing behaviour of domestic Japanese quail (Coturnix coturnix japonica). Crowing activity was continuously recorded in young males maintained in social isolation from the age of three weeks to four months. We observed developmental changes in crow structure, both the temporal and the spectral levels. Speed and trajectories of these developmental changes exhibited an unexpected high inter-individual variability. Mechanisms used by quails to transform sounds during ontogeny resemble those described in oscines during the sensorimotor phase of song learning. Studies on vocal non-learners could shed light on the specificity and evolution of vocal learning.

Bird Speech Perception and Vocal Production: A Comparison with Humans

“…This may be more relevant in birds that have the capacity to imitate a wide range of different sounds, and presumably make use of a broader repertoire of articulations, such as parrots. But also birds that do not have this capacity, such as the Japanese quail, may still have a surprisingly diverse phonetic repertoire (Deregnaucourt et al 2009;Guyomarch and Guyomarch 1996) to which perceptual systems may be tuned.…”

Rudimentary substrates for vocal learning in a suboscine

“…This blending of seemingly auditory and vocal function in the RA-like region of phoebes could be close to one of the preconditions necessary for the emergence of vocal learning and provides an important evolutionary bridge between non-vocal-learners and vocal learners. Song ontogeny in phoebes presents similarities to song development of another non-vocal-learner, the Japanese quail (Coturnix coturnix japonica), as both show vocal variability and developmental changes in song structures 37 . The song variability in both species might be associated with the seasonal changes in hormone levels 44 , developmental changes in vocal/ respiratory circuits, or anatomical maturation in vocal organ and peripheral vocal apparatus [45][46][47] .…”

“…In oscines, the development of learned vocalizations starts with soft and highly variable babbling sounds (that is, subsong), as juveniles gradually modify their vocal output by reference to an external model. We expected that the unlearned song of phoebes would first arise already well developed and with limited variability, as seen in another avian non-vocal-learner, quails 37 . As predicted, the early 'prototypes' of the phoebe's two song types emerged as early as 1-2 months after hatching, but these plastic songs remained highly variable and continued to slowly change in song features for the next 7-8 months (Fig.…”

“…Juveniles were hand reared until independence (at post-hatching days [35][36][37][38][39][40]. Due to the limitations on the number of birds collected in the wild, some of these birds were repeatedly used for two or more experiments.…”

Convergent transcriptional specializations in the brains of humans and song-learning birds

“…We first looked for possible specializations in the gene expression profiles of the RA analog from species representing the two other vocal-learning lineages (parrots and hummingbirds) compared to the neighboring arcopallium and comparably located regions of the arcopallium of species representing two experimentally determined vocal-nonlearning lineages (dove and quail) (41, 64, 65). Because the avian samples were run on the zebra finch Agilent microarray, we had to develop a strict filtering pipeline to include only oligonucleotides that mapped to and hybridized to avian genomic DNA across species, yielding a total of 3044 genes each represented by at least one oligonucleotide also present on the human Agilent microarray (SM3).…”