Fireflies are insects very familiar to the vast majority of Vietnamese people back in the day. Because they are not only associated with fields and villages, but also appear in fairy tales and fables. But do you understand anything about this particular insect? Let's find out in the article below.
1. Description information
Fireflies or glow bugs are small beetles collectively known as the family Lampyridae that are luminescent. Fireflies are typical of temperate regions, although most species live in tropical and subtropical regions (about 2000 species). They are carnivores, so they eat insects or snails. They are nocturnal creatures, with males usually having wings and flying on early summer nights. In many species, the female is wingless.
Males, females and larvae emit cold light and are usually orange-red or yellow-green (510 - 670 nm wavelength); In some species, even the eggs are luminescent. It is thought that light plays an important role in their reproductive behavior with the purpose of attracting the opposite sex. However, in larvae, the glow is mainly intended to warn predators, because firefly larvae contain chemicals that have an unpleasant taste and can be toxic to predators. other meat.
2. Characteristics of fireflies
Fireflies are brown and soft-bodied, often with tougher wings than other beetles. Although the females in some individuals look similar to the males, larval-like females have been found in many other types of fireflies. These females can be distinguished from the larvae because they have compound eyes. The most common types of fireflies are nocturnal, although there are diurnal species.
Most diurnal species stay in the dark to be able to glow.
Fireflies are carnivorous insects, so their food is mostly smaller larvae such as snail larvae, even snails. Some are carnivorous, while others feed on pollen and plant nectar. Fireflies that live in moist environments can even eat earthworms.
Currently, there are about 2000 species of fireflies have been discovered, living mainly in temperate, tropical and subtropical regions. You will often find them in fields, forests, swamps. The preferred habitat of fireflies is in warm, moist, and near water areas such as ponds, streams, rivers, and even swamps.
3. Firefly behavior
A few days after mating, the female lays her eggs on or just below the surface of the soil. The eggs hatch after 3-4 weeks and the larvae feed for the rest of the summer. The larvae are commonly referred to as the glowworm, not to be confused with the beetle family Phengodidae or the Arachnocampa fly. Firefly larvae have simple eyes. The term luminous worm is also used for both adults and larvae of species such as Lampyris noctiluca, the common European luminous worm, where only adult flightless females are luminous and flying males are luminous. only about a week and intermittent.
Fireflies hibernate through the winter during their larval stages, which in some species last several years. Some do this by burrowing into the ground, while others find high places or hide under tree bark. They break cocoons in the spring. After a few weeks of feeding, they pupate for one to two and a half weeks and become adults. The larvae of most species are eaten by carnivores or by other larvae, ground slugs, or naked slugs. Some are specialized, having maxillary fissures (jaws) that shoot digestive juices at their prey. Adults change the type of food. Some are carnivorous, while others eat pollen or plant nectar.
Most fireflies are quite irritating and sometimes toxic to vertebrate carnivores. This is at least partly due to the class of pyron steroids known as lucibufagins (LBGs), which are similar to the cardio-stimulating bufadienolites found in some species of toadstools.
4. Firefly life cycle
Like all beetles, fireflies undergo complete transformation with four stages: egg, larva, pupa, and adult.
The life cycle of fireflies begins in mid-summer, with the female mating and laying about 100 eggs in or near the soil surface. Eggs are laid in clusters or individually. They often choose to lay their eggs under humus, where leaves fall and where the soil is less dry. Some fireflies will deposit eggs in plants instead of in soil. Firefly eggs will hatch after about 3-4 weeks.
The eggs of some species of fireflies are even bioluminescent and you can see them glow faintly in the soil. After hatching, firefly larvae will hibernate through the winter, which can last for several years. Some firefly larvae will burrow underground, while others find high places, hiding under tree bark.
They will break the cocoons in the spring. After a few weeks of feeding, they will pupate for 1-2 and a half weeks and become adults. The lifespan of an adult firefly is only about 1-3 weeks. When adult fireflies appear, they have only one goal in life, which is to mate.
5. Bioluminescence in fireflies
Fireflies emit light similar to how glow sticks work. It is the result of a biochemical reaction.
When the chemical reaction that produces light occurs inside a living organism, it is called bioluminescence. Most bioluminescent species live in marine environments, but fireflies are among the terrestrial bioluminescent organisms.
If you look closely at an adult firefly, you can see that its last 2 or 3 abdominal segments look different from those of other species. Those vertebrae include the light-producing organ – an organ that is really efficient at producing light without emitting any heat. Have you ever touched a light bulb that was turned on for a few minutes? It was really hot. If the firefly's light-producing organs give off the same heat, they can burn out.
6. Luciferase and the chemical reaction that makes fireflies glow
In fireflies, the chemical reaction that makes them glow depends on an enzyme called Luciferase. “Lucifer” comes from the Latin “lucis”, which means light, and “ferre” which means to carry. Luciferase literally means light-carrying enzyme.
The bioluminescence of fireflies is formed by the convergence of several factors: calcium, adenosine triphosphate (ATP), the chemical luciferan and the enzyme luciferase in the light organ. When these chemical components combine with oxygen, light is produced.
Scientists have recently discovered that nitric oxide has an important role in bringing oxygen into the light-producing organelle and initiating the reaction. Without nitric oxide, the oxygen molecules would bind to the mitochondria (mitochondrial DNA) on the surface of the light organ cells, and couldn't get inside to trigger the reaction, so light not created. In the presence of nitric oxygen, it will bring oxygen into the organ, combining with other chemicals to emit light.
7. Why do fireflies blink?
The emission of flickering light along with color is unique to this species and by looking at this flicker pattern we should be able to tell them apart. Learning to recognize fireflies in an area requires knowledge of the length, frequency, and rhythm of those flashes. It includes: the interval between waves, the colors they emit, their preferred flight patterns, and how long they blink at night.
Fireflies' blinking rate is controlled by the release of ATP during a chemical reaction. The color (or frequency) of the light produced can be affected by the pH.
That rate also varies depending on the ambient temperature. Low temperatures will reduce their flashing speed.
Even if you are well versed in the flashing of fireflies in an area, it is important to watch out for mimics trying to tease other fireflies in the swarm. Female fireflies are known for their ability to mimic the blinking patterns of other species, a trick they use to lure males closer for an easy meal. Besides, some male fireflies can also catch the blinking patterns of others.
8. Luciferase in biological research
Luciferase is a valuable enzyme for all kinds of biological research, especially as a marker for gene expression. The researchers were able to see gene activity or the presence of bacteria when luciferase helps produce light.
Luciferase is widely used in the testing of food for contamination caused by bacteria.
As a useful tool for research, there is a growing need for luciferase in laboratories and the commercial harvesting of live fireflies has put negative pressure on firefly populations. in many areas. Fortunately, scientists successfully cloned the firefly luciferase gene, Photinus pyralis, in 1985, allowing large-scale production of synthetic luciferase.
But besides that, some chemical companies still extract luciferase directly from fireflies instead of producing and selling the synthetic version exclusively. They have set a bonus level for the fireflies to encourage people to keep fireflies and collect thousands of fireflies right during the peak of the breeding season. In 2008, in a single province of Tennessee, people eagerly accepted money from a company that promised to catch fireflies and freeze approximately 40,000 males. One team's computer modeling suggests that this level of harvest may be unsustainable for firefly populations. With the availability of synthetic luciferase today, it is completely unnecessary to harvest fireflies for profit.
9. Many species of fireflies are on the verge of extinction
In a study published in the journal BioScience, scientists at Tufts University in Massachusetts (USA) said that around the world there are more than 2,000 species of fireflies. In particular, fireflies such as the firefly in Southern England, the synchronized glow firefly in Malaysia and the Appalachian blue ghost firefly are all on the brink of extinction due to the ever-expanding "ecological footprint" of humans. People.
Besides, fireflies are also in danger of disappearing due to pesticide exposure. According to experts, Organophosphates (organic substances containing phosphate radicals) and Neonicotinoids have the effect of killing insects but at the same time killing beneficial insects. According to the same study, although climate change is not considered a current threat to the firefly, future risks of sea level rise and drought could accelerate the species' extinction. .
The swarms of fireflies flickering in the night are one of nature's most captivating spectacles, attracting many tourists from all over the world to admire. Tours to see glowing fireflies have long been popular in Japan, Malaysia and Taiwan (China).
10. Interesting facts about fireflies
The brightest fireflies currently living in the tropics of the United States can reach a length of 5cm. Their light is 150 times brighter than other fireflies.
In Europe, the most common type is the common firefly, known as the Ivanov worm. The unusual name for this beetle is due to Ivan Kupala's belief that it glows at night.
Scientists were able to identify the firefly genome that affects light. And has been successfully introduced into plants, helping the plantations glow at night.
Every year at the beginning of summer in Japan, the firefly festival takes place. Spectators in the garden near the temple accompanies the onset of sunset and with delight watching the incredible flight of a large number of glowing bugs.
Residents in some tropical settlements are still using these bugs, housed in small containers and lanterns to light their homes.
