@article {53115,
	title = {Zebra finches identify individuals using vocal signatures unique to each call type},
	journal = {Nature Communications},
	volume = {9},
	year = {2018},
	month = {Jan-12-2018},
	abstract = {<p>Individual\&nbsp; recognition\&nbsp; is\&nbsp; critical\&nbsp; in\&nbsp; social\&nbsp; animal\&nbsp; communication,\&nbsp; but\&nbsp; it\&nbsp; has\&nbsp; not\&nbsp; beendemonstrated for a complete vocal repertoire. Deciphering the nature of individual signaturesacross call types is necessary to understand how animals solve the problem of combining, inthe same signal, information about identity and behavioral state. We show that distinctsignatures differentiate zebrafinch individuals for each call type. The distinctiveness of thesesignatures varies: contact calls bear strong individual signatures while calls used duringaggressive encounters are less individualized. We propose that the costly solution of usingmultiple signatures evolved because of the limitations of the passivefiltering properties of thebirds\&rsquo;vocal organ for generating sufficiently individualized features. Thus, individual recog-nition requires the memorization of multiple signatures for the entire repertoire of con-specifics of interests. We show that zebrafinches excel at these tasks.</p>
},
	doi = {10.1038/s41467-018-06394-9},
	url = {http://www.nature.com/articles/s41467-018-06394-9},
	author = {Elie, Julie E. and Theunissen, Fr{\'e}d{\'e}ric E.}
}
@article {53114,
	title = {The vocal repertoire of the domesticated zebra finch: a data-driven approach to decipher the information-bearing acoustic features of communication signals},
	journal = {Animal Cognition},
	volume = {19},
	year = {2016},
	month = {Jan-03-2016},
	pages = {285 - 315},
	abstract = {<p>Although a universal code for the acoustic features of animal vocal communication calls may not exist, the thorough analysis of the distinctive acoustical features of vocalization categories is important not only to decipher the acoustical code for a specific species but also to understand the evolution of communication signals and the mechanisms used to produce and understand them. Here, we recorded more than 8000 examples of almost all the vocalizations of the domesticated zebra finch, Taeniopygia guttata: vocalizations produced to establish contact, to form and maintain pair bonds, to sound an alarm, to communicate distress or to advertise hunger or aggressive intents. We characterized each vocalization type using complete representations that avoided any a priori assumptions on the acoustic code, as well as classical bioacoustics measures that could provide more intuitive interpretations. We then used these acoustical features to rigorously determine the potential information-bearing acoustical features for each vocalization type using both a novel regularized classifier and an unsupervised clustering algorithm. Vocalization categories are discriminated by the shape of their frequency spectrum and by their pitch saliency (noisy to tonal vocalizations) but not particularly by their fundamental frequency. Notably, the spectral shape of zebra finch vocalizations contains peaks or formants that vary systematically across categories and that would be generated by active control of both the vocal organ (source) and the upper vocal tract (filter).</p>
},
	keywords = {Acoustic signature, classification, Meaning, Regularization, Songbird, vocalization},
	issn = {1435-9448},
	doi = {10.1007/s10071-015-0933-6},
	url = {http://link.springer.com/10.1007/s10071-015-0933-6},
	author = {Elie, Julie E. and Theunissen, Fr{\'e}d{\'e}ric E.}
}
