Skip to main content
eScholarship
Open Access Publications from the University of California

Illusions vary because of the types of decorations at bowers, not male skill at arranging them, in great bowerbirds

  • Author(s): Doerr, NR
  • Endler, JA
  • et al.

Published Web Location

http://10.0.3.248/j.anbehav.2014.10.022
No data is associated with this publication.
Abstract

© 2014 The Association for the Study of Animal Behaviour. Many animals use extended phenotypes to attract mates, but the availability of suitable resources in the environment can affect the size and form of these signals, with unknown consequences for honest signalling. In some populations of the great bowerbird, Ptilonorhynchus nuchalis, males arrange decorations by size, with smaller decorations placed closer to the bower entrance than larger decorations. This may create a more even background pattern from the female's viewpoint within the bower than if decorations were arranged randomly. Males show consistent, individual variation in the size-distance gradient, which could reflect variation among males in the cognitive skills needed to arrange decorations. We examined whether individual consistency in gradient characteristics is related to a male's skill at decoration arrangement or the types of decorations at bowers. We paired 18 males and switched bower decorations between pairs. We measured gradient characteristics before switching and 4 and 8 days after switching. Gradient characteristics after switching were related to those of the bower from which decorations were received, not to those of the male's own bower before switching. Gradient characteristics were also related to the types of decorations received, including bones and snail shells. These results suggest that variation among males in the size-distance gradient is explained by differences in the availability of decorations at bowers, not the cognitive skills required to arrange decorations. Although variation in gradient characteristics could indicate the male's ability to locate and transport particular decorations, it could also reflect local availability of objects, with no relationship to male quality.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Item not freely available? Link broken?
Report a problem accessing this item