Have you ever switched off the lights at night and thought, “Where did all the colours go?” It may look like everything turns black or gray, but the truth is—colours don’t actually disappear in the dark. They just need light to shine!
Why Do Colours Vanish at Night?
Colours come from light bouncing off objects and entering our eyes. When there’s sunlight or a lamp, red looks red, blue looks blue, and green looks green. But in the dark, our eyes switch to “night vision mode.” We mostly see black, white, and gray, not bright colours.
Glow-in-the-Dark Magic
Some things have a secret power—they glow in the dark!
Fireflies flash green lights like tiny lanterns.
Glow worms twinkle in caves like fairy lights.
Jellyfish in the ocean shine blue or green, lighting up the sea at night.
Why Do Animals Glow?
Animals don’t glow just to look pretty. They glow for important reasons:
To find a mate – Fireflies flash in patterns to attract partners.
To hunt food – Anglerfish use their glowing “lamp” to lure prey.
To scare enemies – Some squids release glowing ink to confuse predators.
To hide or trick – Certain deep-sea creatures glow on their bellies to blend with the faint light above them.
Fluorescence vs. Bioluminescence
Fluorescence
Fluorescence happens when something soaks up light (like sunlight or UV light) and then glows in a different colour.
Example: Some corals and sea turtles look normal in daylight, but under UV light, they glow neon green or pink.
Fun fact: Even scorpions glow bright blue-green under UV light!
Bioluminescence
Bioluminescence is when animals make their own light using special chemicals inside their bodies.
Example: Fireflies, anglerfish, and glowing jellyfish.
They don’t need a lamp or UV light—their body is the lightbulb!
Think of it this way:
Fluorescence = needs outside light to shine.
Bioluminescence = makes its own light in the dark.
Colours in Space
Look up at the night sky—did you know stars aren’t all white? Some shine bluish, reddish, or golden. Telescopes reveal the hidden rainbow of space!
Fun Fact
Some animals, like owls and cats, see colours in the dark much better than humans—thanks to their super-powered night vision.