Defensive masquerade by plants

Abstract

The defensive strategy known as masquerade, or camouflage without crypsis (a type of deception that partly overlaps mimicry) has received little scientific attention in animals, and concerning plants even less. Moreover, when cases of masquerade were described in plants, they were considered as camouflage or other types of defence through mimicry. Masquerade (including in plants) may operate not only through vision, but also via other senses. Here I review several types of published cases of masquerade in plants, although they were not defined as such when published, and propose that there are two different types of masquerade in plants: (1) non-plant-mimicking defensive masquerade, in which they look (or smell) like uninteresting objects to herbivores (look like a stone or an animal, or smell like droppings or carrion, etc.), and (2) plant-mimicking defensive masquerade, in which plants or plant parts do not look appealing for herbivores, not being green, looking dead or old, harbouring insects, already attacked, less nutritious, etc. Defensive masquerade by plants may in many cases be non-exclusive, but serve additional physiological and defensive functions or operate simultaneously with other defences.