Bioluminescence: colour named from nature, meaning and history

Bioluminescence is light made by living organisms through a chemical reaction involving luciferin and luciferase. It appears in many marine animals, some insects like fireflies, fungi, and bacteria, and is most often seen as a blue or green glow in the dark.

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Bioluminescence is common in marine animals and some insects.
The light comes from a reaction between luciferin and luciferase.
It can be used for camouflage, attracting mates, or luring prey.
Dried fish skins once lit coal mines as a safer alternative to candles.

What colour is Bioluminescence?

Bioluminescence is the light that some living things make on their own. It comes from a chemical reaction inside their bodies, which produces visible light. This glow is often blue or green, especially in the sea, but can appear in other colours depending on the species. Bioluminescence is found in many marine animals, some insects like fireflies, certain fungi, and bacteria. The light can be steady or flash in patterns, and is often seen in dark places where sunlight does not reach.

Where does Bioluminescence come from?

The word 'bioluminescence' describes light made by living things. Ancient writers like Aristotle and Pliny the Elder noticed glowing wood and fish. The process was first studied in detail in the 19th and 20th centuries. Scientists found that the light comes from a reaction between luciferin (a pigment) and luciferase (an enzyme), with oxygen. Bioluminescence has evolved many times in nature, first appearing in corals over 500 million years ago.

How is Bioluminescence made?

Bioluminescence is made by a reaction between luciferin and luciferase in the presence of oxygen. In some animals, extra helpers like calcium or magnesium ions are needed. The details of the reaction vary by species, but the result is always the release of light. The exact colour and brightness depend on the type of luciferin and luciferase, and sometimes on other molecules present.

Aequorea victoria. Photo: Ssblakely, Attribution, via Wikimedia Commons

Principle of the counterillumination camouflage of the firefly squid, Watasenia scintillans . When seen from below by a predator, the bioluminescence helps to match the squid's brightness and colour to the sea surface ab — Principle of the counterillumination camouflage of the firefly squid, Watasenia scintillans . When seen from below by a . Photo: Ian Alexander, CC BY-SA 4.0, via Wikimedia Commons

Where Bioluminescence is used

Animals use bioluminescence for many reasons. Some use it to hide from predators by blending in with faint light from above, a trick called counterillumination. Others use it to attract mates or lure prey. In the lab, the luciferase system is used in genetic and medical research to track changes in cells. In the past, dried fish skins were used as a weak light source in mines.

Green around the world

What the green family means from country to country.

🇦🇷 Argentina

A green kerchief is the sign of the campaign for legal abortion. Huge crowds wore it in 2018, and the movement was called the green wave.

Politics and protest Hope Source: Green scarf

🇦🇺 Australia

Green and gold have been the official national colours since 1984 and are worn by national sports teams. They echo the leaves and flowers of the golden wattle.

Festival and celebration Pride Source: National colours of Australia

🇦🇺 Australia

A Test cricketer is given a dark green cap, the baggy green, on first playing for Australia. Many players wear the same faded cap for a whole career.

Festival and celebration Pride Source: Baggy green

🇧🇩 Bangladesh

The green field of the flag stands for the land and its rice fields. Many people also read it as the youth and vigour of the country.

Nature and renewal Politics and protest Hope Source: Flag of Bangladesh

🇧🇬 Bulgaria

The flag is white, green and red. The green band, which took the place of the blue in the Russian flag, is read as the country's forests and farmland.

Politics and protest Nature and renewal Source: Flag of Bulgaria

🇧🇷 Brazil

The green field of the flag is commonly said to stand for the forests. It was first the colour of the House of Braganza, the family of the first emperor.

Politics and protest Nature and renewal Pride Source: Flag of Brazil

Shades and relatives of Bioluminescence

The colour and pattern of bioluminescent light vary by species. Most marine bioluminescence is blue or green, as these colours travel farthest in water. On land, fireflies often glow yellow or green. Some fungi and bacteria also emit light, usually pale green. The chemical details differ, but all use a luciferin and luciferase system.

Questions people ask about Bioluminescence

What colour is bioluminescence usually?

Most bioluminescent light is blue or green, especially in the sea, but some land species like fireflies can glow yellow or green.

Where does the name 'bioluminescence' come from?

The name means 'living light' and refers to light made by living organisms through a chemical reaction.

How is bioluminescent light produced?

It is made by a chemical reaction between luciferin and luciferase, with oxygen, inside the organism.

What is bioluminescence used for in nature?

Animals use it for camouflage, to attract mates, to lure prey, and to communicate with others of their kind.

Good reading and sources

Where this page comes from

The facts on this page come from the Wikipedia article "Bioluminescence", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). Rang rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.

It may contain mistakes. The swatch is an approximation: named colours are not fixed standards, and every screen shows them a little differently. If something is wrong, tell us. Last refreshed 2026-10-03.

Bioluminescence