Erythrism

Erythrism or erythrochroism refers to an unusual reddish pigmentation of an animal's hair, skin, feathers, or eggshells.

The coloring might be a camouflage that helps some members of the species survive on red plants.

[4] There is also consensus that the erythristic mutation is actually a dominant trait among katydid species, albeit a disadvantageous one, due to the overwhelmingly green coloration of most foliage.

Hence, most pink or otherwise vividly colored katydids do not survive to adulthood, and this observation explains their rarity.

[5] Erythrism in leopards is rare, but one study[6] reported that two of twenty-eight leopards seen in camera traps in a South African nature reserve were erythristic, and the authors found records of five other "strawberry" leopards from the region.