By converting ultraviolet light into visible light and reflecting specific visible colors, fluorescent pigments can often provide much brighter, neon-like color than traditional pigments.

Blacklights can illuminate certain biological materials, including blood, teeth, and fingernails, because they contain fluorophores—molecules that visibly glow immediately after exposure to higher-energy light.

View a gallery of biofluorescent animals, which contain cells that emit various colors when exposed to ultraviolet light.

Not all colored materials can become pigments—the process of grinding materials down into smaller particles may destroy the color-producing molecules.

View an animation of how certain chemicals fluoresce—that is, emit visible light after having absorbed higher-energy light, such as ultraviolet radiation.

View a gallery of plants made to shine using ultraviolet-induced visible fluorescence photography, in which organisms re-emit the ultraviolet light they are exposed to in vibrant, glowing colors.

Biofluorescent animals—those that absorb light, such as ultraviolet rays, and re-emit other types of light, such as neon green—include some flying squirrels, scorpions, sea turtles, and platypuses.

Creating a perfect red pigment that is vivid, durable, and nontoxic is likely impossible.

Virtually all plants are biofluorescent because their photosynthesis is powered by chlorophyll, a pigment that glows red as a way to get rid of excess energy when exposed to ultraviolet light.

Organic pigments can be made in a lab or in nature—the term indicates the presence of carbon-hydrogen bonds, not their source.

Starting with red, colorful objects will appear to lose their colors the deeper they are submerged because water scatters light, reducing the amount available to reflect off objects and be observed.

Scientists can simulate 100 years of studio light exposure in 300 hours using a xenon chamber, enabling them to test a pigment's resistance to fading.

Violet is the rarest color in nature because it is the most energetically demanding visible light for pigments to reflect and for nanostructures to scatter.

Bioluminescent organisms produce their own light through chemical reactions involving unstable, energetic molecules, while biofluorescent organisms almost immediately re-emit light shone on them, but at a different wavelength.

Some organisms' colors come from structural color—tiny structures that distinctly scatter different colors of light, eliminating some while reinforcing others that become visible.

Scientists can tag distinct proteins with fluorescent probes that emit different colors, allowing them to visualize multiple biochemical processes simultaneously.

The color of bird feathers comes from a combination of pigments and structural color, with the latter enabling some to glow in ultraviolet light.

The majority of the 100,000 natural compounds that produce colors are pigments, which can be categorized based on their chemical structure.

The same pigments that enable photosynthesis—chlorophyll a and b—are also responsible for giving most plants their green color.

Fossilized pigment granules have enabled scientists to deduce the colors of long-extinct organisms, including dinosaurs.

Because it is observed in organisms that are not closely related, biofluorescence is thought to have emerged independently many times in nature—over 100 in fish alone.

Inorganic pigments—those that lack carbon-hydrogen bonds—typically comprise metal oxide crystals.

Glow sticks feed energy released in chemical reactions to fluorescent dyes

Lead, arsenic, uranium, and other toxic elements were once used in pigments for producing vibrant colors.

The weakest form of light that is dangerous to humans is ultraviolet

The 2008 Nobel Prize in chemistry was awarded for discovering and developing uses for green fluorescent protein—a biomolecule found in some Pacific Northwest jellyfish.

Humans can distinguish about 10 million colors—a number that is limited by photopigments that only activate when exposed to specific wavelengths of light.

Some corals absorb harmful ultraviolet radiation and re-emit it as visible light, thereby protecting symbiotic algae within their tissues and providing them with energy for photosynthesis.

Some organisms can change color by quickly revealing or hiding various pigments, as seen in octopuses, squids, and other cephalopods.

Bioluminescence provides organisms with a method of hunting, defense, or mating

Bioluminescent reaction enzymes are often used in biomedical research

By separating light with tools such as prisms, scientists can reveal the presence and composition of celestial matter by identifying color fingerprints unique to specific elements and molecules.

Solutions of bioluminescent bacteria can create FOMO-inducing living art

Egg yolks and carrots have the same pigments that contribute to the yellow and orange colors of fall foliage.

Massive blooms of microscopic algae called dinoflagellates produce the neon blue light seen in glowing tides.

Synchrotron radiation has revealed the fur color of creatures millions of years old

View illustrations of bioluminescent functions in marine organisms

LEDs emit pure colors, while incandescent bulbs filter white light

View examples of luciferin, the light-emitting molecule behind bioluminescence

Photographer captures glowing flowers in ultraviolet light

Flamingos get their pink color from pigments in their food, but they cannot be any color because their bodies cannot process every type of pigment.

Cow urine, cuttlefish ink, and burned white lead were among the substances used as pigments throughout history.

Studies of tattoo inks have identified over 100 pigments, which have historically included toxic metals but now include organic compounds.

The world's oldest known synthetic pigment—Egyptian blue—was created about 5,000 years ago.

Although they rely on radioactive elements to operate, everyday technologies such as electronic exit signs, some wristwatches, and smoke detectors are not dangerous, unless they are damaged and their radioactive material is inhaled or swallowed.

The oldest colors in the geological record are bright pink pigments from about 1.1 billion years ago, according to researchers.

Bioluminescence may provide a sustainable alternative to electric lighting

Why 75% of ocean animals glow

Bioluminescence became common in the ocean to support survival in dark environments

Gold has a yellowish appearance rather than the silvery color of most metals because of special relativity, which causes gold's electrons to absorb blue light.

Satellites can be used to measure photosynthetic activity worldwide by observing the red, biofluorescent light emitted by chlorophyll in plants.