This is a dyeing poison arrow frog, a frog toxic to predators such as birds due to their skin containing high amounts of alkaloid.
Throughout the animal kingdom, the prey has used warning colors to warn their potential predators that they are dangerous or toxic to consume. An example of this is the black-and-yellow stripes of wasps.
This arrow frog is a bit different, though, as it has two colour forms: yellow stripes on a black background, or white stripes on a black background.
This diversity of colour signals goes against the accepted theory that warning signal colouration should be subject to strong, frequency-dependent selection.
In Amazonian butterflies, for example, it has been demonstrated that the fitness of a phenotype increases with its frequency – the more of these colour forms are around, the more chance a predator population learns to understand the signal and avoid the prey. Warning signals that are novel or unusual should be selected against due to their rarity.
And yet these two colour forms persist.
See the reason behind this phenomenon over at Cosmos.
(Image Credit: University of Jyvaskyla)