@article {53411,
	title = {Context-dependent variation of house finch song syntax},
	journal = {Animal Behaviour},
	volume = {147},
	year = {2019},
	month = {Jan-01-2019},
	pages = {33 - 42},
	abstract = {<p>We explored the role of social context in the syntactical variation of house finch, Haemorhous mexicanus, songs using both traditional song measures and network analysis. In comparison to solo bouts, the bouts of countersinging males had increased syntax diversity, with higher numbers of simple paths and transition types (but not syllable types) in comparison to solo song, which had high sequence consistency. Both the proportion of introductory syllables and the degree (number of transitions to and from those syllables) increased in countersinging bouts and were an important source of syntactic variability. In contrast, courtship bouts included longer songs and longer syllables than both solo and countersinging bouts, but were similar to solo songs in sequence consistency. The longest courtship songs often included concatenated sequences that formed \&lsquo;compound songs\&rsquo;, or repeating strings of main song syllables, which slightly increased the degree of those syllables. Our results suggest that interactions between males are associated with increased syntactic variability in song delivery while female choice favours signals that maintain species-typical syntax and demonstrate fitness in terms of a male\&$\#$39;s capacity to sing extended songs.</p>
},
	keywords = {birdsong, countersinging, courtship, network analysis, sequence consistency, social context, syntax},
	issn = {00033472},
	doi = {10.1016/j.anbehav.2018.11.001},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0003347218303373https://api.elsevier.com/content/article/PII:S0003347218303373?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0003347218303373?httpAccept=text/plain},
	author = {Ciaburri, Ivy and Williams, Heather}
}
@article {52573,
	title = {Call concatenation in wild meerkats},
	journal = {Animal Behaviour},
	volume = {134},
	year = {2017},
	month = {Jan-12-2017},
	pages = {257 - 269},
	abstract = {<p>Repertoire size, frequently determined by the number of discrete call types, has been used to assess vocal complexity in animals. However, species can also increase their communicative complexity by using graded signals or by combining individual calls. Animal call sequences can be divided into two main categories, each subdivided into two classes: repetitions, with either an unlimited or finite number of iterations of the same call type, and mixed call combinations, composed of two or more graded or discrete call types. Social contexts involve a wide range of behaviours and, unlike predation contexts, can be associated with both positive and negative emotions. Therefore, interactions linked to social contexts may place additional demands on an animal\&$\#$39;s communicative system and lead to the use of call com- binations. We systematically documented call combinations produced by wild meerkats, Suricata sur- icatta, a highly social carnivore, in social contexts in their natural habitat. We observed 12 distinct call combinations belonging to all four classes of combination, produced in all the observed behavioural contexts. Four combinations were each produced in a specific context whereas the remaining eight were produced in several contexts, albeit in different proportions. The broad use of combinations suggests that they represent a non-negligible part of meerkat social communication and that they can be used in flexible ways across various behavioural contexts. Comparison with combinations produced in predation contexts indicated that social call combinations are more varied in number of classes and structural complexity than the former, perhaps due to the greater variety of social contexts. However, in meerkats, combinations of functionally referential calls have been documented in predation but not social contexts, suggesting that both social and predation pressures may play a role in the evolution of combinatoriality in animal communication.</p>
},
	keywords = {call combination, meerkat, natural observations, social context, vocal communication},
	issn = {00033472},
	doi = {10.1016/j.anbehav.2016.12.014},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347216303463},
	author = {Collier, Katie and Townsend, Simon W.}
}
