Evolutionary basis and ecological function of body colour transition in the orchid mantis.

The orchid mantis (Hymenopus coronatus) transitions from black-and-red to pink-white coloration during development, a shift driven by the Redboy pigment transporter. This transition serves different ecological functions: red coloration helps hatchlings mimic stink bugs for predator avoidance, while the pink-white coloration of older nymphs provides floral camouflage for both predator avoidance and prey attraction. The Redboy transporter, upregulated by ecdysone, facilitates this shift by exporting red pigments in early stages and importing white pigments in later stages. 
Evolutionary Basis:
Redboy's Role:
The Redboy transporter, a novel ABCG transporter, arose by gene family expansion and positive selection, specifically to handle the transition from red to white coloration, according to research on Nature. 
Hormonal Regulation:
The hormone ecdysone regulates Redboy, ensuring the pigment transition happens at the appropriate developmental stage, according to research on ResearchGate. 
Genetic Adaptation:
The evolutionary changes in Redboy have allowed orchid mantises to adapt their body color to different life stages and ecological niches. 
Ecological Functions:
Aposematic Mimicry (Hatchlings):
The initial black-and-red coloration serves as a warning signal, mimicking the appearance of stink bugs, which are known to be distasteful or toxic to predators.
Camouflage (Older Nymphs):
The pink-white coloration provides floral camouflage, helping the mantis blend in with flowers and avoid detection by predators.
Prey Attraction:
The flower-like appearance also attracts unsuspecting prey, such as small insects, to their location, enhancing the mantis's hunting success. 
In summary, the orchid mantis's body color transition is a fascinating example of ontogenetic camouflage and adaptive evolution, where the color changes throughout the mantis's life serve distinct ecological roles in where the color changes throughout the mantis's life serve distinct ecological roles in predator avoidance and prey attraction.