Supplementary material from "Discriminating between similar alarm calls of contrasting function"
Posted on 2020-04-21 - 08:57
In a pioneering study of signal design, Marler (Marler 1955 Nature176, 6–8; Marler 1957 Behav. 11, 13–37) argued that the contrasting acoustic design of hawk (seet) and mobbing alarm calls of European passerines reflected their contrasting function. Hawk alarms were high-frequency tones, warning conspecifics to flee but making localization difficult for predators, while mobbing calls were broadband and harsh, allowing easy localization and approach. Contrasting signal features are also consistent with signal detection theory. Discriminating these calls quickly is critical for survival, because hawk alarms require immediate escape. These signals should therefore be selected to be easy to discriminate, reducing the trade-off between immediate fleeing to hawk alarms and unnecessary fleeing to mobbing alarms. Despite these expectations, hawk and mobbing alarm calls of superb fairy-wrens, Malurus cyaneus, are surprisingly similar, raising the question of discriminability without contextual cues. We synthesized these calls on computer, made intermediates and used playbacks to test whether calls can be discriminated acoustically, and if so by what features. We found that birds used multiple acoustic features when discriminating calls, allowing fast discrimination despite overlap in individual parameters. We speculate that the similarity of fairy-wren alarm calls could enhance detectability of both signals, while multiple subtle acoustic differences reduce a trade-off with discriminability.This article is part of the theme issue ‘Signal detection theory in recognition systems: from evolving models to experimental tests'.
CITE THIS COLLECTION
DataCiteDataCite
3 Biotech3 Biotech
3D Printing in Medicine3D Printing in Medicine
3D Research3D Research
3D-Printed Materials and Systems3D-Printed Materials and Systems
4OR4OR
AAPG BulletinAAPG Bulletin
AAPS OpenAAPS Open
AAPS PharmSciTechAAPS PharmSciTech
Abhandlungen aus dem Mathematischen Seminar der Universität HamburgAbhandlungen aus dem Mathematischen Seminar der Universität Hamburg
ABI Technik (German)ABI Technik (German)
Academic MedicineAcademic Medicine
Academic PediatricsAcademic Pediatrics
Academic PsychiatryAcademic Psychiatry
Academic QuestionsAcademic Questions
Academy of Management DiscoveriesAcademy of Management Discoveries
Academy of Management JournalAcademy of Management Journal
Academy of Management Learning and EducationAcademy of Management Learning and Education
Academy of Management PerspectivesAcademy of Management Perspectives
Academy of Management ProceedingsAcademy of Management Proceedings
Academy of Management ReviewAcademy of Management Review
Tegtman, Natalie T.; Magrath, Robert D. (2020). Supplementary material from "Discriminating between similar alarm calls of contrasting function". The Royal Society. Collection. https://doi.org/10.6084/m9.figshare.c.4946085.v1