Fireflies are living lanterns. How do fireflies glow? Why the firefly glows is interesting for children

A firefly is an insect that belongs to the order Coleoptera (or beetles), suborder heterophagous, family fireflies (lampyridae) (lat. Lampyridae).

Fireflies get their name because their eggs, larvae and adults are capable of glowing. The oldest written mention of fireflies is in a Japanese poetry collection from the late 8th century.

Firefly - description and photo. What does a firefly look like?

Fireflies are small insects ranging in size from 4 mm to 3 cm. Most of them have a flattened oblong body covered with hairs and a structure characteristic of all beetles, in which they stand out:

• 4 wings, the upper two of which have turned into elytra, having punctures and sometimes traces of ribs;

• movable head, decorated with large faceted eyes, completely or partially covered by the pronotum;

• filiform, comb or saw-shaped antennae, consisting of 11 segments;

• mouthparts of the gnawing type (more often observed in larvae and females; in adult males it is reduced).

The males of many species, which resemble ordinary beetles, are very different from the females, which more closely resemble larvae or small worms with legs. Such representatives have a dark brown body on 3 pairs of short limbs, simple large eyes and no wings or elytra at all. Accordingly, they cannot fly. Their antennae are small, consisting of three segments, and their hard-to-see head is hidden behind the neck shield. The less developed the female, the more intensely she glows.

Fireflies are not brightly colored: representatives of brown color are more common, but their covers can also contain black and brown tones. These insects have relatively soft and flexible, moderately sclerotized body coverings. Unlike other beetles, the elytra of fireflies are very light, so the insects were previously classified as soft beetles (lat. Cantharidae), but then separated into a separate family.

Why do fireflies glow?

Most members of the firefly family are known for their ability to emit a phosphorescent glow, which is especially noticeable in the dark. In some species, only males can glow, in others, only females, in others, both (for example, Italian fireflies). Males emit a bright light in flight. Females are inactive and usually glow brightly on the soil surface. There are also fireflies that do not have this ability at all, while in many species the light comes even from the larvae and eggs.

By the way, few sushi animals even exhibit the phenomenon of bioluminescence (chemical glow). The larvae of fungus gnats, springtails (collembolas), fire flies, jumping spiders and representatives of beetles, for example, such as fire-bearing click beetles (pyrophorus) from the West Indies, are known to be capable of this. But if we count marine inhabitants, then there are at least 800 species of luminous animals on Earth.

The organs that allow fireflies to emit rays are photogenic cells (lanterns), abundantly intertwined with nerves and tracheas (air tubes). Externally, lanterns look like yellowish spots on the underside of the abdomen, covered with a transparent film (cuticle). They can be located on the last segments of the abdomen or evenly distributed throughout the body of the insect. Beneath these cells lie others filled with uric acid crystals and capable of reflecting light. Together, these cells work only if there is a nerve impulse from the insect’s brain. Oxygen enters the photogenic cell through the trachea and, with the help of the enzyme luciferase, which accelerates the reaction, oxidizes the compound of luciferin (light-emitting biological pigment) and ATP (adenosine triphosphoric acid). Thanks to this, the firefly glows, emitting light blue, yellow, red or Green colour.

Males and females of the same species most often emit rays of similar colors, but there are exceptions. The color of the glow depends on temperature and acidity (pH) environment, as well as on the structure of luciferase.

The beetles themselves regulate the glow; they can strengthen or weaken it, make it intermittent or continuous. Each species has its own unique system phosphorus radiation. Depending on the purpose, the glow of fireflies can be pulsating, flashing, stable, fading, bright or dim. The female of each species reacts only to the male’s signals with a certain frequency and intensity of light, that is, his mode. With a special rhythm of light emission, beetles not only attract partners, but also scare away predators and protect the boundaries of their territories. There are:

• search and calling signals in males;
• signals of consent, refusal and post-copulatory signals in females;
• signals of aggression, protest and even light mimicry.

Interestingly, fireflies spend about 98% of their energy emitting light, while an ordinary electric light bulb (incandescent lamp) converts only 4% of the energy into light, the rest of the energy is dissipated as heat.

Diurnal fireflies often do not need the ability to emit light, which is why they lack it. But those daytime representatives who live in caves or in dark corners of the forest also turn on their “flashlights”. The eggs of all types of fireflies also emit light at first, but it soon fades away. During the day, the light of a firefly can be seen if you cover the insect with two palms or move it to a dark place.

By the way, fireflies also give signals using the direction of flight. For example, representatives of one species fly in a straight line, representatives of another species fly in a broken line.

Types of firefly light signals

V. F. Buck divided all light signals of fireflies into 4 types:

• Continuous glow

This is how adult beetles belonging to the genus Phengodes glow, as well as the eggs of all fireflies without exception. Neither external temperature nor lighting affects the brightness of the rays of this uncontrollable type of glow.

• Intermittent glow

Depending on factors external environment and the internal state of the insect, it can be weak or strong light. It may completely fade away for a while. This is how most larvae shine.

• Ripple

This type of luminescence, in which periods of light and absence of light are repeated at regular intervals, is characteristic of the tropical genera Luciola and Pteroptix.

• Flashes

There is no time dependence between the intervals of flashes and their absence with this type of glow. This type of signal is typical for most fireflies, especially in temperate latitudes. In a given climate, the ability of insects to emit light is highly dependent on environmental factors.

HA. Lloyd also identified a fifth type of glow:

• Flicker

This type of light signal is a series of short flashes (frequency from 5 to 30 Hz), appearing directly one after another. It is found in all subfamilies, and its presence does not depend on the location and habitat.

Firefly communication systems

Lampyrids have 2 types of communication systems.

1. In the first system, an individual of one sex (usually a female) emits specific calling signals and attracts a representative of the opposite sex, for whom the presence of their own light organs is not mandatory. This type of communication is typical for fireflies of the genera Phengodes, Lampyris, Arachnocampa, Diplocadon, Dioptoma (Cantheroidae).
2. In the second type of system, individuals of the same sex (usually flying males) emit calling signals, to which flightless females give sex- and species-specific responses. This method of communication is characteristic of many species from the subfamilies Lampyrinae (genus Photinus) and Photurinae, living in Northern and South America.

This division is not absolute, since there are species with an intermediate type of communication and with a more advanced interactive luminescence system (in the European species Luciola italica and Luciola mingrelica).

Synchronized flashing of fireflies

In the tropics, many species of beetles from the family Lampyridae seem to shine together. They simultaneously light their “lanterns” and extinguish them at the same time. Scientists call this phenomenon the synchronous flashing of fireflies. The process of synchronous flashing of fireflies has not yet been fully studied, and there are several versions regarding how insects manage to shine at the same time. According to one of them, within a group of beetles of the same species there is a leader, and he serves as the conductor of this “chorus”. And since all representatives know the frequency (break time and glow time), they manage to do this very amicably. Mostly male lampyrids flash synchronously. Moreover, all researchers are inclined to believe that the synchronization of firefly signals is associated with the sexual behavior of insects. By increasing population density, their ability to find a mating partner increases. Scientists also noticed that the synchrony of insect light can be disrupted by hanging a lamp next to them. But with the cessation of its work, the process is restored.

The first mention of this phenomenon dates back to 1680 - this is a description made by E. Kaempfer after a trip to Bangkok. Subsequently, many statements were made about the observation of this phenomenon in Texas (USA), Japan, Thailand, Malaysia and the mountainous regions of New Guinea. There are especially many of these types of fireflies in Malaysia: there the locals call this phenomenon “kelip-kelip.” In the United States, in Elcomont National Park (Great Smoky Mountains), visitors watch the synchronous glow of representatives of the species Photinus carolinus.

Where do fireflies live?

Fireflies are fairly common, heat-loving insects that live in all parts of the world:

• in North and South America;
• in Africa;
• in Australia and New Zealand;
• in Europe (including the UK);
• in Asia (Malaysia, China, India, Japan, Indonesia and the Philippines).

Most fireflies are found in the Northern Hemisphere. Many of them live in warm countries, that is, in tropical and subtropical regions of our planet. Some varieties are found in temperate latitudes. Russia is home to 20 species of fireflies, which can be found throughout the territory except the north: in Far East, in the European part and in Siberia. They can be found in deciduous forests, swamps, near rivers and lakes, and in clearings.

Fireflies do not like to live in groups; they are loners, but they often form temporary clusters. Most fireflies are nocturnal animals, but there are also those that are active during daylight hours. During the day, insects rest on the grass, hide under bark, stones or in mud, and at night those that are able to fly do so smoothly and quickly. In cold weather they can often be seen on the surface of the ground.

What do fireflies eat?

Both larvae and adults are often predators, although there are fireflies that feed on the nectar and pollen of flowers, as well as decaying plants. Carnivorous bugs prey on other insects, cutworm caterpillars, mollusks, centipedes, earthworms, and even their fellow insects. Some females living in the tropics (for example, from the genus Photuris), after mating, imitate the rhythm of the glow of the males of another species in order to eat them and get nutrients for the development of their offspring.

Females in adulthood feed more often than males. Many males do not eat at all and die after several matings, although there is other evidence that all adults eat food.

The firefly larva has a retractable tassel on the last abdominal segment. It is needed in order to clean off the mucus remaining on its small head after eating slugs. All firefly larvae are active predators. They mainly eat shellfish and often live in their hard shells.

Reproduction of fireflies

Like all Coleoptera, fireflies develop with complete metamorphosis. The life cycle of these insects consists of 4 stages:

1. Egg (3-4 weeks),
2. Larva, or nymph (from 3 months to 1.5 years),
3. Pupa (1-2 weeks),
4. Imago, or adult (3-4 months).

Females and males mate on the ground or on low plants for 1-3 hours, after which the female lays up to 100 eggs in depressions in the soil, in garbage, on the lower surface of leaves or in moss. The eggs of common fireflies look like pearly yellow pebbles washed with water. Their shell is thin, and the “head” side of the eggs contains the embryo, which is visible through the transparent film.

After 3-4 weeks, the eggs hatch into terrestrial or aquatic larvae, which are voracious predators. The body of the larvae is dark, slightly flattened, with long running legs. In aquatic species, lateral abdominal gills are developed. The small elongated or square head of nymphs with three-segmented antennae is strongly retracted into the prothorax. There is 1 light eye on each side of the head. The strongly sclerotized mandibles (mandibles) of the larvae are shaped like a sickle, inside of which there is a sucking canal. Unlike adult insects, nymphs do not have an upper lip.

The larvae settle on the soil surface - under stones, in the forest floor, in mollusk shells. Nymphs of some firefly species pupate in the same fall, but mostly they survive the winter and only turn into pupae in the spring.

The larvae pupate in the soil or by hanging themselves on the bark of a tree, as they do. After 1-2 weeks, beetles crawl out of the pupae.

General life cycle fireflies lasts 1-2 years.

Types of fireflies, photos and names.

In total, entomologists count about 2,000 species of fireflies. Let's talk about the most famous of them.

• Common firefly ( aka large firefly) (lat. Lampyris noctiluca) has the popular names Ivanov worm or Ivanovsky worm. The appearance of the insect was associated with the holiday of Ivan Kupala, because it is with the arrival of summer that the mating season begins for fireflies. This is where the popular nickname came from, which was given to a female very similar to a worm.

The large firefly is a beetle with the characteristic features of fireflies. appearance. The size of males reaches 11-15 mm, females – 11-18 mm. The insect has a flat, villous body and all other characteristics of the family and order. The male and female of this species are very different from each other. The female looks like a larva and leads a sedentary, ground-based lifestyle. Both sexes have the ability to bioluminescence. But in the female this is much more pronounced; at dusk she emits a rather bright glow. The male flies well, but glows very faintly, almost imperceptibly to observers. Obviously, it is the female who gives the signal to her partner.

• - a common inhabitant of Japanese rice fields. Lives only in wet mud or directly in water. Hunts at night on mollusks, including intermediate hosts of fluke worms. When hunting, it shines very brightly, emitting a blue light.

• lives on the territory North America. Males of the genus Photinus glow only during takeoff and fly in a zigzag pattern, while females use mimetic illumination to eat males of other species. From representatives of this genus, American scientists isolate the enzyme luciferase to use it in biological practice. The common eastern firefly is the most common in North America.

This is a nocturnal beetle with a dark brown body 11-14 mm long. Thanks to the bright light, it is clearly visible on the soil surface. The females of this species look like worms. Fire photinus larvae live from 1 to 2 years and hide in damp places - near streams, under bark and on the ground. They spend the winter buried in the ground.

Both adult insects and their larvae are predators, eating worms and snails.

• lives only in Canada and the USA. An adult beetle reaches a size of 2 cm. It has a flat black body, red eyes and yellow underwings. On the last segments of its abdomen there are photogenic cells.

The larva of this insect is nicknamed the “glow worm” for its ability to bioluminescence. The worm-like females of this species are also capable of light mimicry, imitating the signals of the firefly species Photinus in order to grab and eat their males.

• Cyphonocerus ruficollis- the most primitive and little-studied species of fireflies. It lives in North America and Eurasia. In Russia, the insect is found in Primorye, where females and males actively glow in August. The beetle is included in the Red Book of Russia.

• Red firefly (firefly pyrocoelia) (lat. Pyrocaelia rufa) is a rare and little-studied species that lives in the Russian Far East. Its length can reach 15 mm. It is called the red firefly because its scutellum and rounded pronotum have an orange tint. The beetle's elytra are dark brown, the antennae are saw-toothed and small.

The larval stage of this insect lasts 2 years. You can find the larva in the grass, under stones or on the forest floor. Adult males fly and glow.

• - a small black beetle with an orange head and saw-shaped antennae (antennae). The females of this species fly and glow, but the males lose the ability to emit light after turning into an adult insect.

Fir fireflies live in the forests of North America.

• - inhabitant of the center of Europe. The male beetle has clear transparent spots on the pronotum, and the rest of its body is light brown. The body length of the insect varies from 10 to 15 mm.

Males glow especially brightly in flight. Females are worm-like and are also capable of emitting bright light. The organs of light production are located in Central European worms not only at the end of the abdomen, but also in the second segment of the chest. The larvae of this species can also glow. They have a black fuzzy body with yellow-pink dots on the sides.

On a summer night, fireflies present a bewitching and wonderful sight when, as in a fairy tale, colorful lights twinkle like little stars in the darkness.

Their light is red-yellow and green shades, of various durations and brightness. firefly insect belongs to the order Coleoptera, a family that contains about two thousand species, distributed in almost all parts of the world.

The most striking representatives of insects settled in the subtropics and tropics. There are approximately 20 species in our country. Firefly in Latin it is called: Lampyridae.

Sometimes fireflies emit a longer light in flight, like shooting stars, flying and dancing lights against the backdrop of the southern night. In history there are interesting facts about the use of fireflies by people in everyday life.

For example, chronicles indicate that the first white settlers who sailed to Brazil on sailing ships Where Same fireflies live, illuminated their homes natural light.

And the Indians, when going hunting, tied these natural lanterns to their toes. And bright insects not only helped to see in the dark, but also scared away poisonous snakes. Similar feature of fireflies Sometimes it is customary to compare the properties with a fluorescent lamp.

However, this natural glow is much more convenient, because by emitting their lights, insects do not heat up and do not increase body temperature. Of course, nature took care of this, otherwise it could lead to the death of fireflies.

Nutrition

Fireflies live in grass, in bushes, in moss or under fallen leaves. And at night they go hunting. Fireflies eat, small, larvae of other insects, small animals, snails and rotting plants.

Adult fireflies do not feed, but exist only to procreate, dying after mating and the process of laying eggs. Unfortunately, the mating games of these insects sometimes lead to cannibalism.

Who would have thought that the females of these impressive insects, which adorn the divine summer night, often have an insanely insidious character.

Females of the Photuris species, giving deceptive signals to males of another species, only lure them as if for fertilization, and instead of the desired intercourse, they devour them. Scientists call this behavior aggressive mimicry.

But fireflies can also be very useful, especially for humans, by eating and eliminating dangerous pests in fallen leaves of trees and in vegetable gardens. Fireflies in the garden- This good omen for the gardener.

In, where the most unusual and interesting views These insects, fireflies love to settle in rice fields, where they eat, destroying in abundance, freshwater snails, clearing the plantations of unwanted voracious villagers, bringing invaluable benefits.

Reproduction and lifespan

The light that fireflies emit comes in different frequencies, which helps them during mating. When the time comes for the male to procreate, he goes in search of his chosen one. And it is she who distinguishes him as her male by the shade of light signals.

The more expressive and brighter the signs of love, the more chances a partner has to please a charming potential companion. In the hot tropics, among the lush vegetation of forests, gentlemen even arrange for their supposed chosen ones a kind of light and music group serenades, lighting and extinguishing luminous lantern lights that sparkle cleaner than the neon lights of big cities.

At the moment when the large eyes of the male receive the necessary light signal-password from the female, the firefly descends nearby, and the spouses greet each other with bright lights for some time, after which the process of copulation takes place.

Females, if copulation occurs successfully, lay eggs, from which large larvae emerge. They are terrestrial and aquatic, mostly black with yellow spots.

The larvae have incredible gluttony and an incredible appetite. They can consume shells and mollusks, as well as small invertebrates, as desirable food. They have the same glowing ability as adults. Saturated in the summer, when cold weather sets in, they hide in tree bark, where they remain for the winter.

And in the spring, as soon as they wake up, they begin to actively eat again for a month, and sometimes more. Then the pupation process begins, which lasts from 7 to 18 days. After which, adult individuals appear, ready to once again surprise others with their charming radiance in the dark. The lifespan of an adult is about three to four months.

Fireflies - a luminous miracle of nature

The flying, flickering lights of fireflies are a real mystical attraction in the summer. But how much do we know about what fireflies are? Here are some facts about them.

1. What are fireflies?
Fireflies are nocturnal insects - they lead active image life at night. They are members of the winged beetle family Lampyridae (meaning "to shine" in Greek). The name "firefly" is a little misleading because of the more than 2,000 species of fireflies, only a few of these species have the ability to light up.

2. Besides fireflies, there are other types of glowing species.
Fireflies are probably one of the most popular species due to their ability to glow. Most bioluminescent creatures live in the ocean—people have little contact with them. Their light is created through a chemical reaction in which oxygen combines with calcium, adenosine triphosphate (ATP) and luciferin using the enzyme luciferase. Fireflies use their bioluminescence probably to ward off predators.

3. Not all fireflies have “fire”
Fireflies, most of their species, simply do not burn. Non-bioluminescent fireflies, which do not produce light, are generally not nocturnal bugs—they are most active during the day.

4. Scientists discovered luciferases thanks to fireflies
The only way to obtain the chemical luciferase is to extract it from fireflies. Eventually, scientists figured out how to create synthetic luciferases. But some people still collect enzyme from "flying lanterns." Luciferase is used in scientific research for food safety testing and some forensic procedures.

5. Fireflies are energy efficient
Firefly lights are the most efficient energy sources in the world. One hundred percent of the energy they create is emitted through light. By comparison, an incandescent light bulb emits only 10 percent of its energy as light, while fluorescent light bulbs emit 90 percent of its energy as light.

6. Their light show is mating acts.
Most flying male fireflies are looking for a mate. Each species has a specific light pattern that they use to communicate with each other. After the female sees the male and responds to his affection, she responds to him with the same light pattern. Usually females sit on plants, waiting for a male.

7. Some species have the ability to synchronize their blinking
Scientists aren't sure why fireflies do this, but some theories suggest that fireflies do it to become more visible. If a group of fireflies blink in a single pattern, they are likely doing so to attract the attention of females. The only firefly species in America that blinks synchronously is Photinus carolinus. They live in national park USA Great Smokies, where the park service organizes an evening light show for visitors.

8. Not all fireflies shine the same way.
Each species has its own specific color of light. Some produce a blue or green glow, while others glow orange or yellow.

9. They taste disgusting
Unlike cicadas, fireflies cannot be cooked into grilled bugs. If you try to eat firefly, it will taste bitter. The bugs can even be toxic. When fireflies are attacked, they shed drops of blood. Blood contains chemicals that create a bitter taste and poison. Most animals know this and avoid chewing fireflies.

10. Fireflies sometimes practice cannibalism
When fireflies are still in their larval stage, they are ready to feast on snails. Usually, when they mature, they become vegetarians - they move away from meat. Scientists believe that adult fireflies live off nectar and pollen, or do not eat at all. But others, fireflies such as Photuris, can enjoy eating them own kind. Photuris females often eat males of other genera. They attract unsuspecting beetles by mimicking their light patterns.

11. Their numbers are decreasing
There are several reasons why firefly populations are declining, including climate change and habitat destruction. When a firefly's habitat is disturbed due to road or other construction, they do not migrate to a new location, but simply disappear.

12. Enjoy the firefly light show while you can.
Researchers know little about fireflies and have no clear answer as to why they are disappearing. Enjoy the light show while this insect still exists in nature. Perhaps the generations of people who will come after us will not be given such an opportunity to see these beetles with their amazing mystical glow.

Hello my nature lovers! Have you ever seen tiny yellow-green lights in the grass at night? No? Well, then you certainly read Dragunsky’s “He is alive and glowing”! Do you understand who I'm talking about? Absolutely right, about fireflies!

In our distant childhood, we caught them and hid them in matchboxes, and when we came home, we locked ourselves in the bathroom and, lifting the lid, watched in the dark as the tiny bug burned like a magic lantern.

Children have always been curious, why do fireflies glow, why do they wink at us, and how long are they ready to give their light? That’s why today I suggest you figure out how this living flashlight works.

Lesson plan:

How does a firefly work?

Let's start with the fact that the firefly, which we affectionately nicknamed the firefly among the common people, is a beetle from the class of insects. He leads a nocturnal lifestyle; during the day he sleeps in the grass and “comes out” in the dark. Today, the firefly family has about 2 thousand species, of which there are only 15 in our country. Their greatest diversity lives in tropical and subtropical countries.

Most beetles have a single luminous organ located at the tip of their abdomen.

It consists of three layers:

• the first, lower one, reflects light like a mirror,
• the third, upper one, allows the glow to pass through, since it is transparent,
• the second, middle one, is the most interesting, because this is where the magic happens, photogenic cells sit there, “turning on” the light.

Some species have many such light-emitting organs instead of just one, and they are distributed throughout the body.

In the production of fireflies of light lies chemical reaction, which involves:

• a heat-resistant substance called luciferin,
• a substance that speeds up the reaction process called luciferase,
• and an acid with the complex name adenositrifosphoric.

How do they negotiate among themselves so that the firefly turns on its flashlight? Luciferin is oxidized by that same acid with a difficult name under the influence of oxygen and, with the participation of luciferase, starts the luminescence process. Are you confused?

Luciferin + acid ATP + oxygen + luciferase = flashlight.

Interestingly, fireflies do not have lungs, and they take oxygen, so necessary for oxidation, through tubes - tracheas. By supplying oxygen, insects can regulate their glow. Open the oxygen duct - it glows, shut off the oxygen - it goes out.

What exactly does the light emitted by beetles depend on? The enzyme luciferase is responsible for the shade, which different types fireflies are different. In addition to it, the color spectrum is influenced temperature regime and alkaline environment. That is why on one side of our planet fireflies glow with one color, and on the other - completely different.

This is interesting! It's not just adult insects that glow. In the firefly family, the flashlight turns on even before birth - at the egg, larva and pupa stages.

They are so romantic

Why and for whom do fireflies burn in the dark? Surely not for us, wandering in the dark.

It turns out that these naturally romantic natures “sing” love serenades to their ladies and invite them on a date, and the beetles’ glow is nothing more than a means of communication, a kind of beacon for the opposite sex.

With the help of a wink, they can offer to meet, “nod” with light music in response and agree, refuse a “cup of coffee” and stop shining, or they can get angry and use a bright light to indicate the exit and “show the door.”

In addition to romantic communication between “boys” and “girls,” light for beetles is a means of warning their relatives about danger.

This is interesting! Tropical fireflies are usually large sizes. In general, by the way, these insects can be from 4 millimeters to 2 centimeters long. So, southern lanterns can glow so brightly that many residents of tropical countries used to illuminate their homes with the help of these insects. How? Yes, it’s very simple: we sat them in the lamps, and they were happy to try, they turned on to the fullest!

How do fireflies wink?

Each species of this family winks in its own way, with its own specific light. True, there are also beetles in which “boys” may blink differently from “girls.” Scientists have studied many representatives of fireflies and combined their signaling alphabet into 4 main types. So, fireflies can light up:

• continuous glow, that is, constantly and brightly,
• intermittent glow, when at first the beetle “burns” brightly for a long time, then the saturation of the radiation changes and completely stops, then the insect lights up again,
• by pulsations, in which the light flashes at a certain time interval,
• through outbreaks that occur randomly in the beetle depending on external factors.

In this case, the energy of fireflies is converted into light by 87-98 percent. If we compare, an incandescent lamp converts only 5% of its energy into visible light!

Fireflies also know how to regulate their glow, making it brighter and dimmer, interrupting it and resuming it again. There are such tropical artists who spoil the locals with choral performances, lighting up all together at the same time, like a flash mob.

This is interesting! Particularly brave ladies who lived in ancient times in South America decorated their evening attire with a living diamond - a large tropical firefly that sparkled like a precious stone in the dark.

Well, have you figured out the structure of a living flashlight? If you are in a forest or field in the dark, pay attention, maybe next to you there will be one that is alive and glowing!

And now it's unreal beautiful video! Literally a miracle of nature! The firefly cave, although these are not our fireflies, but New Zealand ones. But very, SOOOOO beautiful)

In general, there are many interesting and beautiful things in nature:

• read, for example, about sea jellyfish;
• or about the most unusual animals in the world;
• and even about the most poisonous ones.

Don't forget to add to our VKontakte group and subscribe to blog news.

Enjoy your studies)

Everyone has heard about fireflies; many people have even seen them more than once. They are distributed almost all over the world, and each of the two thousand species has the ability to emit a mysterious, golden-green light. In this way, insects not only signal their location, but also distinguish between “friends” and “strangers” by a special flickering frequency. But have you ever wondered how exactly this magic happens? After all, the tiny bug does not work from a power outlet...

"Flashlight" device

Most often, the luminescent organ of these beetles - the photophore - is located at the end of the abdomen and, in its principle, really resembles an ordinary flashlight. The photophore consists of three layers. The bottom layer, mirror, is capable of reflecting light. The top layer is a translucent cuticle. But the most interesting thing happens in the middle layer, where photogenic cells, or photocytes, are located. They produce light through the intensive use of oxygen.

Insects do not have lungs, and oxygen is transmitted through an extensive network of tubes (tracheoles) and stored in the mitochondria of cells. For quick selection required quantity oxygen, the firefly’s body produces nitric oxide, which, entering the mitochondria, displaces oxygen from them. The switching on and off of these processes is regulated nervous system insects

Luminescence or fluorescence?

In the popular press, organisms that exhibit both fluorescence and luminescence are called luminous. Both processes occur in nature (sometimes in the same organisms) and are currently being actively studied by biologists, geneticists, pharmacists and engineers. But if fluorescence involves the passive re-emission of light with a slight decrease in energy and a corresponding shift in wavelength, then luminescence is an active process during which chemical energy is converted into light.

Enzymes that convert chemical energy into luminescence are called luciferases, and their substrates (organic pigments) are called luciferins. Both words come from the Latin "lucifer", which in turn is composed of the Latin roots lux "light" and fero "carry". Despite the same name, there is very little in common between luciferases and luciferins, apart from their actual function: they have different structure, different origins and they work differently.

The most studied is the glow system of fireflies - bioluminescence. Luciferase catalyzes a reaction during which the ATP molecule (the universal unit of cellular energy) activates the luciferin pigment, after which oxygen is added to it. “Magic” occurs at the moment when CO2 is separated from oxidized luciferin: the dye molecule finds itself in an excited state, leaving which it emits a quantum of light. It is interesting that in all organisms, despite the independent emergence of the luminescence system, it is in one way or another connected precisely with oxidation.

What determines the color of the glow?

In principle, the light produced by luciferase can be almost any shade, from blue-green to red. In fireflies, in particular, the glow refers to the visible yellow-green part of the spectrum, corresponding to wavelengths from 500 to 600 nm. At the same time, the light emitted by fireflies does not produce heat - it does not contain infrared and ultraviolet rays. Unlike a conventional electric lamp, where the bulk of the energy turns into useless heat, and the efficiency is 5-10%, fireflies convert up to 98% of the expended energy into light radiation.

However, in nature there are many other living organisms that emit light - corals, jellyfish, deep-sea fish... Their cells contain both luciferase and fluorescent proteins (for example, the well-known GFP). They are not just located in the same cell, but are so closely connected with each other that a quantum excitation transfer effect occurs: the photon produced by luciferase, without being emitted, is transferred to GFP, which emits it with a changed wavelength.

Therefore, the inhabitants of the deep sea, as well as glowing mice, piglets, fish and other living creatures created on the basis of the GFP protein extracted from them, glow green - although their luciferase is initially configured to Blue colour. The use of GFP makes it possible to increase the efficiency of radiation due to the fact that the fluorescent protein, compared to luciferin in such organisms, is less inclined to lose its excited state without emitting a light quantum. Fireflies (like luminescent bacteria) do not have proteins like GFP, and in this respect their glow system is simpler.

A little romance...

Scientists believe that bioluminescence is a means of intersexual communication for fireflies. Tropical and North American species of fireflies sometimes perform entire choral serenades for their partners. Having gathered on one tree, they first blink each at their own time. Then the pair of insects begins to do this in sync. A little time passes, and gradually all the insects begin to emit short flashes of light together and at the same time. After half an hour, the whole tree behaves like a single living organism, and it may seem that it is simply decorated with an electric garland of light bulbs.

The females respond to them with the same light music, flashing on and off with the whole flock. True, by our standards you cannot call them the “fair sex”: in their appearance, wingless female fireflies resemble larvae. The firefly, not bothering with such trifles, flies to its friend... but is eaten. For example, female fireflies of the Photuris species imitate the glow of the Photinus species and attract alien males. By eating deceived (and bitterly disappointed in love) males, predators receive not only food, but also protection from birds and spiders, since their prey contains a special chemical.

However, the ability to glow helps to attract the opposite sex even to other species - in particular, to us humans. The famous entomologist Evelyn Chisman wrote in her articles in 1932 that some extravagant ladies, before evening celebrations, decorated their dresses and even their hair with fireflies, and in the dark they seemed strewn with diamonds. However, the main “romantic” version of the glow of these insects also has some incomprehensible moments. It does not explain why the larvae, pupae, and even eggs of fireflies, which are usually buried in the soil, glow (only slightly weaker).