What, if anything, is the adaptive function of countershading?

@article{Ruxton2004WhatIA,
  title={What, if anything, is the adaptive function of countershading?},
  author={Graeme D. Ruxton and Michael P Speed and David J. Kelly},
  journal={Animal Behaviour},
  year={2004},
  volume={68},
  pages={445-451}
}
Countershading, the gradation of colour from dark on the dorsum to light on the ventrum, is generally considered to have the effect of making organisms difficult to detect. The mechanism that facilitates this form of crypsis is often considered to be concealment of shadows cast on the body of the animal. We review the current empirical evidence for the cryptic function of countershading and for the mechanism underlying it. We argue that there is no conclusive evidence that countershading per se… Expand

Figures from this paper

From Abbott Thayer to the present day: what have we learned about the function of countershading?
  • Hannah M. Rowland
  • Biology, Medicine
  • Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2008
TLDR
The evidence to support each of the possible explanations for countershading is examined, such as protection from UV or abrasion, and thermoregulation, and discusses the need for future empirical work. Expand
Towards an ecology of protective coloration
TLDR
It is concluded that many protective coloration mechanisms can be employed simultaneously, particularly in conjunction with background matching, and that broad‐scale ecological studies of defence strategies that incorporate phylogenetics are still very much in their infancy. Expand
Countershading enhances crypsis with some bird species but not others
TLDR
It was apparent that blackbirds were taking countershaded baits least often, but blue tits and robins conferred no special advantage to countershade baits, suggesting that the efficacy of countershading may vary with species of predator. Expand
Countershading enhances cryptic protection: an experiment with wild birds and artificial prey
TLDR
The results show that countershading can enhance cryptic protection and has important implications for the evolutionary ecology of prey defences. Expand
Countershading is related to positional behavior in primates
TLDR
The results suggest that countershading is weak or absent in species of any size that often adopt vertical postural positions because a crypsis benefit is only gained when being horizontal. Expand
A Quantitative Test of the Predicted Relationship between Countershading and Lighting Environment
TLDR
This work investigated whether countershading functions as self-shadow concealment (SSC) in ruminants and calculated “optimal” countershaded for SSC by measuring illumination falling onto a model ruminant as a function of time of day and lighting environment. Expand
3D Camouflage in an Ornithischian Dinosaur
TLDR
This study presents a study of an exceptionally well-preserved specimen of Psittacosaurus sp. Expand
Can't tell the caterpillars from the trees: countershading enhances survival in a woodland
TLDR
These experiments provide the first demonstration, in an ecologically valid visual context, that shadowing on bodies (such as lepidopteran larvae) provides cues that visually hunting predators use to detect potential prey species, and that countershading counterbalances shadowing to enhance cryptic protection. Expand
Testing the role of background matching and self‐shadow concealment in explaining countershading coloration in wild‐caught rainbowfish
TLDR
The role of the light environment and predation risk in determining DPD in wild-caught populations of a freshwater fish, the western rainbowfish, is determined and the underlying mechanisms of DPD for concealment are examined, including background matching and self-shadow concealment. Expand
Interspecific Variation in Primate Countershading: Effects of Activity Pattern, Body Mass, and Phylogeny
  • J. Kamilar
  • Biology
  • International Journal of Primatology
  • 2009
TLDR
Variation in primate countershading is related to body mass and phylogeny, but not to activity pattern, according to species values and phylogenetically independent contrasts. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 44 REFERENCES
The ontogeny and distribution of countershading in colonies of the naked mole-rat (Heterocephalus glaber)
TLDR
Alternative hypotheses for pigmentation that were considered include: thermoregulation, and protection from abrasion or from damaging ultraviolet radiation, which do lead to different predictions regarding the development of pigmentation and which colony members should be countershaded. Expand
INTENSITY REGULATION OF BIOLUMINESCENCE DURING COUNTERSHADING IN LIVING MIDWATER ANIMALS
TLDR
It is suggested that the concealment strategy of ventral bioluminescent countershaders is limited to depths greater than 350-400 m, largely because of the high visual acuity of predators and the high cost of producing countershading luminescence at lesser depths. Expand
Countershading: Universally deceptive or deceptively universal?
  • R. Kiltie
  • Biology, Medicine
  • Trends in ecology & evolution
  • 1988
TLDR
The presence of dark dorsa and light ven tra on animals is often attributed to an adaptive effect of shape-obliteration when illumination is from above, but direct evidence for this effect is scant and alternative explanations for the evolution of the trait are given less attention. Expand
Adaptive Significance of Seabird Coloration: The Case of Procellariiforms
TLDR
Correlations between coloration and species body size, diet, feeding techniques, foraging group sizes, and climate at breeding localities found were similar, suggesting coloration may be related to procellariiform life histories, possibly acting through competition and predation risk. Expand
GRAVITY AND LIGHT INFLUENCE THE COUNTERSHADING REFLEXES OF THE CUTTLEFISH SEPIA OFFICINALIS
TLDR
Brain lesions provide evidence that the pathways for the CSRs run through the lateral basal lobes in the supraoesophageal part of the brain. Expand
Testing thayer's countershading hypothesis: An image processing approach
TLDR
A method for assessing the shadow-reducing effect of countershading by digital image processing is described and grey squirrels, Sciurus carolinensis, are used in this study because of the availability of skins. Expand
White underparts in gulls function as hunting camouflage
TLDR
Black-headed gulls allowed to hunt schooling bleak in an indoor pool showed a significantly higher reduction, in prey capture rates than a control group of five white gulls, which support the idea of hunting camouflage. Expand
Countershading by physiological colour change in the fish louse Anilocra physodes L. (Crustacea: Isopoda)
TLDR
The appearance and distribution of the chromatophore stages indicate the possibility of physiological colour change in Anilocra, and the fish louse probably achieves adaptive countershading and thus additional protection from predators, advantageous for both parasite and host. Expand
Hunting Strategies of a Lake Malawi Cichlid with Reverse Countershading
Tyrannochromis macrostoma (Regan), a haplochromine cichlid fish endemic to Lake Malawi, Africa, exhibits reverse countershading. It attacks potential prey fishes from an upright, sideways (90*Expand
Correlation between body color and behavior in the upside-down catfish, Synodontis nigriventris
TLDR
It was found that the catfish preferred the black background to the white one, and when melatonin was added to the bathing water, the fish became pale and swam restlessly even when they were exposed to the black Background. Expand
...
1
2
3
4
5
...