A test of a hierarchical signalling model in song sparrows

William A. Searcy, Adrienne L. DuBois, Karla Rivera-Cáceres, Stephen Nowicki

Research output: Contribution to journalArticlepeer-review

12 Scopus citations


Hierarchical signalling may be a common adaptation for aggressive signalling. In this strategy an animal progresses through a series of discretely different signals of escalating level of threat before eventually proceeding to physical aggression. A model of such hierarchical aggressive signalling has been proposed for song sparrows, Melospiza melodia, in which a core part of the sequence is: song type match. → soft song. → attack. The model predicts that song type matching is a strong predictor of soft song, but only aweak predictor of attack. We used a two-part playback design to test these predictions, with an initial edge playback from just off the subject's territory using a song type that the subject could match, followed by a centre playback from a speaker placed well within the territory. Each male was tested twice with this design. We found that matching the edge playback did not predict soft song production at the centre. A second strong threat, wing waving, was actually negatively associated with matching. Matching the edge playback also was not associated with physical measures of aggression such as approach and latency to approach. Thus, this particular model of hierarchical aggressive signalling was not supported for our study population. Song type matching in our study population may have some function not associated with aggressive signalling to the matched individual, or no function at all.

Original languageEnglish (US)
Pages (from-to)309-315
Number of pages7
JournalAnimal Behaviour
Issue number2
StatePublished - Aug 2013


  • Aggressive signalling
  • Hierarchical aggressive signaling
  • Melospiza melodia
  • Playback
  • Soft song
  • Song production
  • Song sparrow
  • Song type matching
  • Threat display

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Ecology, Evolution, Behavior and Systematics


Dive into the research topics of 'A test of a hierarchical signalling model in song sparrows'. Together they form a unique fingerprint.

Cite this