Egg colour matching in an African cuckoo, as revealed by ultraviolet-visible reflectance spectrophotometry

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dc.contributor.authorCherry M.I.
dc.contributor.authorBennett A.T.D.
dc.date.accessioned2011-05-15T16:00:26Z
dc.date.available2011-05-15T16:00:26Z
dc.date.issued2001
dc.description.abstractDespite major differences between human and avian colour vision, previous studies of cuckoo egg mimicry have used human colour vision (or standards based thereon) to assess colour matching. Using ultraviolet-visible reflectance spectrophotometry (300-700 nm), we measured museum collections of eggs of the red-chested cuckoo and its hosts. The first three principal components explained more than 99% of the variance in spectra, and measures of cuckoo-host egg similarity derived from these transformations were compared with measures of cuckoo-host egg similarity estimated by human observers unaware of the hypotheses we were testing. Monte Carlo methods were used to simulate laying of cuckoo eggs at random in nests. Results showed that host and cuckoo eggs were very highly matched for an ultraviolet versus greenness component, which was not detected by humans. Furthermore, whereas cuckoo and host were dissimilar in achromatic brightness, humans did not detect this difference. Our study thus reveals aspects of cuckoo-host egg colour matching which have hitherto not been described. These results suggest subtleties and complexities in the evolution of host-cuckoo egg mimicry that were not previously suspected. Our results also have the potential to explain the longstanding paradox that some host species accept cuckoo eggs that are non-mimetic to the human eye.
dc.description.versionArticle
dc.identifier.citationProceedings of the Royal Society B: Biological Sciences
dc.identifier.citation268
dc.identifier.citation1467
dc.identifier.issn9628452
dc.identifier.other10.1098/rspb.2000.1414
dc.identifier.urihttp://hdl.handle.net/10019.1/11693
dc.subjectavifauna
dc.subjectcolor
dc.subjectegg
dc.subjectmimicry
dc.subjectarticle
dc.subjectbird
dc.subjectcolor vision
dc.subjectegg
dc.subjectevolution
dc.subjectnonhuman
dc.subjectparasitism
dc.subjectpriority journal
dc.subjectreflectometry
dc.subjectAnimals
dc.subjectBirds
dc.subjectColor
dc.subjectColor Perception
dc.subjectEggs
dc.subjectFemale
dc.subjectHumans
dc.subjectMaternal Behavior
dc.subjectMonte Carlo Method
dc.subjectSongbirds
dc.subjectSpecies Specificity
dc.subjectSpectrophotometry
dc.subjectAves
dc.subjectCuculidae
dc.titleEgg colour matching in an African cuckoo, as revealed by ultraviolet-visible reflectance spectrophotometry
dc.typeArticle
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