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Why do fireflies disappear?

Fireflies live in some slightly humid environments such as rivers and forests, and there is no light pollution, water pollution and noise. However, now more and more high-rise buildings have replaced the former forests and grasslands; More and more water pollution and light pollution have greatly changed the living environment, and fireflies are no longer suitable for survival.

Fireflies are 4- 18 mm long; The body is flat, mostly black, reddish brown or brown; The head is hidden under the chest backboard, and the antenna 1 1 is filiform and comb-shaped. Compound eyes are developed; The front chest backboard is mostly semicircular; The basal segment of the forefoot is conical, and the forefoot has a subunit segment.

The basal segment of hind foot is transverse and the tarsal segment is 5-5-5; Coleoptera wings are flat and wide, covering the ventral end, and there are many ridges on the wing surface; There are 7-8 segments in the abdomen and 2 segments (male) or 1 segment (female) at the end, which contains phosphorite luminescent substances, which can emit yellow-green light under the action of luminescent enzymes; Female insects have no wings.

Extended data

Eggs, larvae, pupae and adults of fireflies can emit light. The glow of firefly larvae is considered to have the function of warning and intimidating natural enemies, while adults are considered to use flash to identify species, courtship and trap.

Usually, male fireflies will emit a specific flash when flying in the air, and female fireflies will send out a response signal, so that male fireflies can find and locate female fireflies. The duration and interval of female fireflies' flashing are species-specific, so it can provide species information, gender information and location information to male fireflies. However, in the male competition of the same firefly, the pressure of natural selection makes the courtship ceremony of male fireflies more and more complicated and lasts longer and longer before mating.

Female fireflies don't simply choose the male fireflies with the strongest flash brightness. Factors such as the size, moving speed and mating guard posture of male individuals also determine the choice of female fireflies for male fireflies. When the female fireflies of Photinus concimilis compete with many male fireflies, they will choose those male fireflies whose flashing frequency is higher than the average and the flashing time is close to the average. There are many researches on the flashing AC signal of fireflies abroad, but there are few researches in China except Taiwan Province Province.

As a carrier of information, the amount of information contained in light varies with the degree of modification of the light carrier. The information contained in the flash signal, the sending and receiving of the flash signal are all factors that affect the sexual communication of fireflies.

The frequency, spectrum and intensity of the flash signal and the distribution of these parameters in time and space can all be regarded as the coding of the signal. A single flash signal contains the following parameters: spectral composition, shape of light emitter, flash signal mode and light motion.

Baidu Encyclopedia-Firefly