Plant Camouflage, Explained
Camouflage is a common defense strategy for animals such as Arctic foxes and butterflies. It helps them blend in with their surroundings and protects them from potential enemies. In contrast, when we think of flowers and fruit, we often think of how they use bright colors and appealing patterns to attract attention, e.g., for fertilization and seed dispersal. Plant concealment, on the whole, is not a subject of much public attention.
A recent study led by the Kunming Institute of Botany of the Chinese Academy of Sciences shows, however, that some plants adopt camouflage methods for better survival. The study, “Plant Camouflage: Ecology, Evolution, and Implications,” was published online in Trends in Ecology & Evolution.
Camouflage tactics
Plants use several major tactics to fool dangerous predators. One of the most common is background matching. For example, Corydalis benecincta, a plant with purple flowers and delicate round leaves, changes color to match brown rocks.
Another interesting tactic is decoration, i.e., when plants cover themselves with materials from the environment. This is more widely seen in coastal and dune plants that are passively covered by sand grains, thus making them less conspicuous.
Besides blending in with their surroundings, some plants, like cowpea seeds, use disruptive colors (e.g., high-contrast spots and stripes) to prevent their true edges and outlines from being recognized.
Masquerading is a tactic used by plants to resemble unimportant objects in the environment that a predator would normally ignore. For example, Lithops Terricolor, a succulent with thick leaves and stems containing a lot of water, bears a canny resemblance to small grey rocks in order to escape the attention of predators.
What Factors Influence Plant Camouflage?
Despite these diverse tactics, many plants are more limited than animals when it comes to camouflage. One of the most crucial reasons is photosynthesis: Most plants have to stay green to survive and thrive, which means changing colors becomes challenging and costly.
However, several factors facilitate the use of camouflage. For example, for seeds that don’t rely on photosynthesis, concealment is more possible. Plant size is another important factor. According to the study, camouflage is often found in small herbs, juveniles and seeds. Since most plants grow in an open habitat and are unable to escape, camouflage becomes an important way of avoiding being detected or repeatedly attacked by predators.
The research was supported by the Second Tibetan Plateau Scientific Expedition and Research, a TPE-related science project.
