Fireflies light up to provide mating signals and warnings to predators

Some female fireflies mimic the signals of other species to lure in and eat them

The genus Photuris does not produce its own defensive pheromones to ward off predators, so it has developed mimicry to attract males of firefly species that do. Unsuspecting males are consumed after these chemicals—lucibufagins—are extracted.

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

Unlike glow sticks, bioluminescent reactions use renewable resources like oxygen and ATP. This ability allows fireflies to mate and deter predators, anglerfish to confuse and attract prey, and deep-sea shrimp to defend themselves by vomiting glowing slush.

Spiders may manipulate captured male fireflies into mimicking female mating signals

Rather than killing a male firefly captured in its web, the Araneus ventricosus spider bites into it, which researchers believe injects a venom that disrupts normal flashing behavior and produces a form of mimicry to attract additional males. (Some readers may experience a paywall.)

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.

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.

View illustrations of bioluminescent functions in marine organisms

Bioluminescence can startle predators, camouflage, lure prey, confuse rivals, or facilitate mate recognition. One tactic—the burglar alarm—involves an organism releasing light to attract a larger predator to its attacker as a means of defense.

View a gallery of bioluminescent organisms, including jellyfish and mushrooms

Some species produce a quick flash of light, while others glow steadily with an eerie glow, often to seek attention or in response to being disturbed. Snails, worms, fungi, and other organisms highlight that this ability evolved independently, rather than from one common ancestor.

Watch David Attenborough's documentary on bioluminescent creatures, which have been observed using light for hunting, mating, communication, and self-defense, and number in the thousands of species.

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

Despite seeming like a rare ability in land animals and unseen in plants, bioluminescence has evolved at least 29 times across marine species, indicating its necessity for survival where hiding spots are rare and highlighting how environments provide evolutionary pressure.

Humans have used bioluminescence as a means of military advantage

During World War I, the British Navy sank a German U-boat after spotting the blue light forming at the sides and in the wake of the boat. Jellyfish slime was applied to a Roman walking stick for nighttime guidance, while bioluminescent fungi in Indonesia fulfilled the same purpose.

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

Bioluminescent marine organisms rely on various unique luciferins, including Cypridina-type luciferin in seed shrimp and chlorophyll-based dinoflagellate luciferin, to react with oxygen to produce light. These chemicals require unique catalysts to help them bind with oxygen.

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.

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

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.

Dragonfly migration season is believed to run from August to November

Researchers know much less about dragonfly migrations than they do about bird or whale migrations. However, North America may have up to 18 migratory dragonfly species. A recent study revealed that the species undertakes complex long-distance migrations every year that span generations and seem to be influenced by temperature, making them particularly vulnerable to climate change.

Why 75% of ocean animals glow

About 75% of ocean creatures can make their own light. It's called bioluminescence—and it all comes down to a special chemical reaction happening inside their bodies.

View a sample of the bioluminescent tree of life

This diagram shows 42 different light-producing organisms, from bacteria and fungi to worms, fish, and crustaceans. It illustrates how the ability to produce light has appeared multiple times across the tree of life, rather than stemming from a single ancestor.

Some North American bats can glow in the dark

After examining 60 museum specimens from six different species, scientists found that all of them emitted light after being exposed to ultraviolet radiation. Researchers are perplexed by this natural phenomenon and are currently unable to deduce the reason behind it.

Fireworks' chemical composition and internal layout produce their unique displays

The burning of different metal compounds, facilitated by combining fuel with oxidizers, results in explosions of varying colors. The timing and pattern are engineered through the arrangement of pellets and fuses.

Listen to what a forest in the Jurassic Period may have sounded like with this reconstructed soundscape, which was created by analyzing the fossilized wings of 165 million-year-old insects.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

Auroral myths include Valkyries, firefoxes, and torchlight from giants fishing at night

In Norse mythology, the light displays were considered reflections from the Valkyries' armor as the female warriors brought the souls of heroes to Valhalla. In Finland, firefoxes were thought to move so fast that they created sparks in the sky as their tails brushed against mountains.

As many as 100,000 fire ants can interlock with one another and form a living raft to save their colony when at risk of drowning in rising water.

Tracking butterfly migration via the pollen they collect

Trillions of insects migrate around the world each year, but many are too small to track with physical trackers, leaving their migratory routes a mystery. In recent years, scientists have utilized pollen grains collected from butterflies to analyze which plants that pollen originated from—providing substantial data to infer the insect's specific route. Research has shed light on many insects' migrations since, including the Painted Lady butterfly. Read more and see a map here.

The first appearance of bioluminescence was at least 540 million years ago

After analyzing fossils, genetic data, and statistical methods, scientists believe octocorals were the first organisms to evolve light-producing abilities. As a result of independent evolution across at least 94 species, this phenomenon is connected to a diverse range of behaviors.

Metamorphosis evolved over millions of years as species that hatched as smaller versions of adults started exhibiting genetic mutations that differentiated juvenile and adult bodies.

Fruit fly experiments helped identify genes responsible for major body development

The insects' fast life cycle and affordability have allowed geneticists to quickly identify which genes are responsible for limbs, eyes, and other body structures by inducing mutations. The same genes may be responsible for different parts of a species' body, such as limb-building genes being responsible for wing pigmentation in butterflies.

Bioluminescence may provide a sustainable alternative to electric lighting

French start-up Glowee is experimenting with lights made from bioluminescent microorganisms in public spaces to reduce energy use. While the technology shows promise, challenges remain with brightness, maintenance, and scaling it for widespread use.

Bioluminescent reaction enzymes are often used in biomedical research

Near-infrared luciferase systems allow researchers to image and analyze cellular activity in living animals because they penetrate tissue more deeply than visible light. This provides a means of studying gene expression and protein interactions without harming the animals.

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

Chameleons change color by altering the spacing of nanocrystals under their skin, which changes what colors of light are absorbed and reflected.

Solutions of bioluminescent bacteria can create FOMO-inducing living art

A 2002 exhibition at Montana State University-Bozeman placed the bacteria onto petri dishes that served as macroscopic pixels to create images. Once the bacteria finished eating all the food in the sealed dishes, the light slowly faded away, ending the exhibit.

Some dinosaurs evolved night vision and acute hearing for nocturnal hunting

Paleontologists analyzed the fossilized eye and ear structures of 16 theropods, finding that some had owl-like hearing and huge pupils. These characteristics are consistent with modern-day nocturnal species, including nightjars and geckos.

Research shows that during total solar eclipses, some animals change their behavior to match their nighttime activities.

Fruit fly sperm are gigantic—about 40 times larger than human sperm, according to scientific research published in June 2026.

Fruit fly experiments show personality emerges, in part, from genetic factors

A 2025 study revealed that fruit flies exhibit unique behavioral preferences, akin to personalities, which could be artificially selected for when breeding to modify behavioral variability. This variability can be adaptive in unpredictable environments.

Mosquitoes even have olfactory receptors on their sperm.

Catfish have taste buds spread across their entire skin, making their whole body function like a tongue that can taste food several feet away.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

Light pollution is giving oysters insomnia

Oysters, bivalve mollusks that have light-detecting cells along their skin, can't sleep with all this artificial light. According to a 2022 study, oysters' sleep cycles are disturbed by light dimmer than that provided by the full moon. As with humans, it's possible that these bouts of insomnia could have adverse health effects and contribute to the development of disease over time.

Understanding ball lightning remains an area of active research

Observations of glowing orbs of light that appear during or after thunderstorms have been documented since at least the 12th century, but their rarity and short lifetimes have made their study challenging. Some theories suggest they form when lightning vaporizes pockets of gases in the air or certain materials on the ground.

Single-cell organisms have circadian clocks that direct daily biochemical routines

Cyanobacteria, a type of light-sensitive bacteria, use this clock to signal when to alternate between making organic compounds through photosynthesis and when to convert atmospheric nitrogen into usable ammonia. Upregulating photosynthetic machinery before dawn helps ensure efficient photosynthesis.

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.

Twin studies helped scientists understand why mosquitoes like some of us more than others

A combination of carbon dioxide output, skin chemistry, genetic factors, hormones, and clothing choice can make us particularly vulnerable to mosquito bites. Watch how mosquitoes responded to one man in the video versus his wife, a research approach typically conducted with identical and fraternal twins to test mosquito attractiveness.

Fireworks make a loud booming sound after explosion due to air expanding faster than the speed of sound.

Fluorescent bulbs can be illuminated by overhead power lines without making contact

The electromagnetic fields produced by the alternating current in transmission lines can induce the motion of charges in nearby objects. This motion yields electric currents that can light up bulbs but are too small to harm humans.

Fireworks contribute to air, water, and soil contamination and disrupt wildlife

Fireworks displays have far-reaching environmental consequences, including acid rain from displays during storms and microplastic pollution in water supplies. Wildlife has also been seen abandoning sites during fireworks and never returning.

Why scientists are making robot insects

Insects have much to teach us about flying, jumping, moving quickly, and more. So, roboticists are studying how insects do the ridiculous things they do, like walk on water or jump fifty times their body height, to inform their design and engineering of a new slate of robots: tiny ones. Learn the future of this type of robot with this fascinating video with insights into both insects and robots.

Artificial lightning can improve the yield of shiitake mushroom growers

Researchers have found that shockwaves produced from lightning strikes homogenously break internal filaments called hyphae, transitioning the mushrooms from a vegetative growth to a fruiting phase. Repeated minor shocks near mushroom logs mimicked this effect.