The English zoologist Edward Bagnall Poulton, author of The Colours of Animals (1890) discovered the countershading of various insects, including the pupa or chrysalis of the purple emperor butterfly, Apatura iris, … See more

Hannah Rowland, reviewing countershading 100 years after Abbott Thayer, observed that countershading, which she defines as "darker pigmentation on those surfaces exposed to the most lighting" is a common but poorly understood aspect of See more

Evolutionary developmental biology has assembled evidence from embryology and genetics to show how evolution has acted at all scales from the … See more

• Synodontis nigriventris, an "upside-down" catfish (with reverse countershading)
• Counterchanging, a heraldic device of similar appearance See more

In animals
Countershading is observed in a wide range of animal groups, both terrestrial, such as deer, and marine, such as sharks. It is the basis of camouflage in both predators and prey. It is used alongside other forms of … See more

Despite demonstrations and examples adduced by Cott and others, little experimental evidence for the effectiveness of countershading was gathered in the century since Thayer's discovery. Experiments in 2009 using artificial prey … See more

If countershading paints out shadows, the reverse, darkening the belly and lightening the back, would maximise contrast by adding to the natural fall of light. This pattern of See more