Photo : matters of survival
Fern in Volcano Sibayak. (Photoshop to blur surrounding, add sharpness.)
To us, it is nature beauty. But to the plant, it is matter of survival. The high intensities of ultraviolet and infrared from Sun light in high altitude, can damage any young leaf shots. The red colour from anthocyanins act as a sun block by reflecting excessive energy from ultraviolet and infrared light.