A red ladybug appears red in white light, red in red light, and black in blue light.
When a ladybug is red it means that its shell reflects the red light, or the radiation between 650-700 nm, from the visible spectrum. A white light is composed of all colours, the whole visible spectrum, therefore, the ladybug shell will reflect the red colour. When considering a red light over a red ladybug, the ladybug will again appear red because the spectrum in which there is reflection of colour from its shell is present. On the other hand, when blue light is put over a red ladybug, the ladybug will appear black as there is no light that its shell can reflect.
