10.5061/DRYAD.HF8QF
Barnett, James B.
University of Bristol
Redfern, Annabelle S.
University of Bristol
Bhattacharyya-Dickson, Robin
University of Bristol
Clifton, Olivia
University of Bristol
Courty, Thomas
University of Bristol
Ho, Thien
University of Bristol
Hopes, Annabel
University of Bristol
McPhee, Thomas
University of Bristol
Merrison, Kaitlin
University of Bristol
Owen, Robert
University of Bristol
Scott-Samuel, Nicholas E.
University of Bristol
Cuthill, Innes C.
University of Bristol
Data from: Stripes for warning and stripes for hiding: spatial frequency
and detection distance
Dryad
dataset
2016
detection distance
background matching
coloration
aposematism
camouflage
2016-10-24T14:31:24Z
2016-10-24T14:31:24Z
en
https://doi.org/10.1093/beheco/arw168
194679 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Striped patterns are common in nature and are used both as warning signals
and camouflage. Their effectiveness in either role depends on their color
and spatial frequency, and how these compare to the background. Although
this general principle is well established, the specific detail of how
visual texture influences defensive coloration remains untested in the
field. For aposematic patterns, especially, little work has focused on how
pattern components, as opposed to color, affect warning signal efficacy.
By presenting artificial moth-like stimuli, pinned to tree bark, to wild
avian predators, and human observers, we examine how the spatial frequency
and orientation of stripes affects the survival and detectability of
yellow-and-black (aversive) and olive-and-black (cryptic) patterns. For
the cryptic stripes, we find that matching the dominant spatial frequency
and orientation of the background increases survival against bird
predation and decreases the distance from which humans first detect the
target. For aversive stripes, however, survival against birds peaked at
spatial frequencies that neither matched the dominant background spatial
frequency nor maximized the mismatch between target and background. This
peak in survival at intermediate spatial frequencies did not match
detectability by humans: there was no difference in the initial detection
distance between stripes of different spatial frequencies, although the
distance at which stripes could be resolved did differ. We suggest that,
although the best cryptic strategy is to match the dominant components of
the background as closely as possible, the optimal aposematic signal is
one that balances signal distinctiveness and recognition at a distance.
survivaldata_1ASurvival data from Experiment 1Asurvivaldata_1BSurvival
data from Experiment 1BdetectiondataDetection and identification data from
Experiment 2