Why do insects bark?

The pine beetle looks very handsome. It is wearing a black or brown coat, metallic luster, dotted with some white spots. Looks simple and generous. There are seven tassels at the ends of the two short tentacles of the male worm [tassels: this refers to the tassel-like pendants made of colored feathers or silk thread, which refers to the tentacles of scarab. ), with the change of insect's mood, tassels will unfold or close like fans.

People may first think that this gorgeous decoration is a highly sensitive sensory organ, which can capture subtle smells, weak sound waves and other changes that humans cannot detect. What about women? The image of female insects seems to remind people not to think too much and think too far. Female insects who take the responsibility of loving mothers need at least as sensitive sensory organs as male insects, or even more. But there are only six tassels at the end of the female antenna, and they are narrow and short.

So, what's the use of a pair of folding fans for male insects? The folding fan of scarab, like the long beard and shovel-shaped upper jaw of longicorn, is a sign of mature courtship, but its appearance is different.

Scarabs are the most punctual in the insect calendar. It appeared on the solstice of summer and was born at the same time as the first cicada. When the day becomes the longest and the sun turns the crops golden, the scarab rushes to the Woods on time. In those days, when night came, bugs would visit the pine trees near my home.

I seized the opportunity to follow them and observe them. The males spread the folding fan at the end of the antenna with passion, and quietly flew repeatedly to the branches where the females stopped. Their black figures passed through the last afterglow of the sunset, flying and stopping, hovering left and right. This scene will last for half a month. What are they busy with?

Obviously, they are talking to beautiful women. Be diligent and stick to it until late at night every day. The next morning, the male and female insects usually stop on the low branches, in pairs, motionless, ignoring the things around them. Even if someone catches them with their hands, they won't run away. Most scarabs chew pine needles in their mouths and hook branches with their hind paws, showing a look of contentment. Some people even dozed off there with pine needles. It was not until dusk came again that they flew into the sky again.

It is impossible to observe them dancing in the air. So in the morning, I caught four pairs while they were dozing off, put them in a spacious barbed wire fence, and put some pine branches in to let them rest. Waiting and waiting, they just refused to perform aerial dancing. Because they can't fly high at most, a male insect flies close to its object, opens its folding fan and shakes it gently, as if to ask, "Can you accept my love?" It is showing off its beauty, especially the folding fan. Unfortunately, the female insect is motionless and seems indifferent to its flattery. The female worm has not been freed from the depression caused by the loss of freedom. I can't observe the further interaction between them. They may not mate until late at night, and I can't wait for the best time.

I am particularly interested in the fact that pine beetles have musical talent, and even females can sing. Do men summon and seduce the opposite sex by singing? Does the female insect also echo the male insect's song with her song? Under normal circumstances, both of them live happily on the branches of pine trees. It's possible that people will follow suit and the husband and wife will sing in chorus. It's a pity that I didn't hear them echoing each other in the tree or singing in the barbed wire. I can't testify

Scarabs are obvious at the end of the abdomen. As soon as the worm's abdomen expands and contracts, the last section of the abdomen rubs against the hind wings of Coleoptera, producing sound. There are no special vocal organs on the surface of abdominal segment and COLEOPTERA. Even if you look at it carefully with a magnifying glass, you can't see the fine stripes for pronunciation. Both sides are bare. So how did the sound come from?

You wet your index finger and rub it back and forth on the glass plate, making a scarab-like sound. If you put an eraser on the glass, the sound will be exactly the same as that of scarab. If you can master a certain rhythm, it is no different from the singing of scarab. Scarab's flexible abdomen is rubber, and COLEOPTERA's thin and hard hind wings are glass. It can be seen that the pronunciation principle of scarab is very simple.

A few other COLEOPTERA insects also have the same characteristics. For example, dung beetles also make sounds by rubbing the hind wings of Coleoptera through the expansion and contraction of their abdomen.

Anoplophora longissima also makes sounds by friction, but the parts are different. The front pectoral webbed of Anoplophora longicorn extends backward into a protrusion, just inserted into the depression of the middle thoracoabdominal plate. The friction between the two is like rubbing the glass with wet fingers and making a sound. I once dialed the protruding net on the dead longicorn to make it make a sound, but it was useless. Because it requires the cooperation of the whole chest.

However, it is also a longhorn beetle, because it lacks this protuberance, so it can't make a sound and becomes dumb.

Although we have mastered the principle of scarab pronunciation, why it sings is still a mystery. Singing courtship? It's possible. However, despite my special attention, I never heard the scarab singing in the middle of the night. Even in the barbed wire, I can't hear their songs.

Scarab singing is not difficult. Just hold it in your hand and touch it, and it will sing. Sing until you don't offend it anymore. That voice doesn't sound like singing, but more like complaining and protesting against fate. Strangely, in the scarab world, singing is used to express pain, while silence is a sign of joy.

Other insects that make sounds by rubbing their breasts or abdomen are similar. The female cricket, who is hiding in the hole to lay eggs, groans when she is suddenly frightened; The captured longicorn beetle will try its best to sing. When the danger was over, they stopped shouting.

Some insects also sing for self-entertainment, courtship and celebration of happiness and sunshine. Most of these insects will keep silent when they are in danger.

When something happened, Weaver Girl stopped singing. On the contrary, once they catch cicadas, they shout loudly, much louder than usual. The owl's song can express both sadness and joy, so that it is difficult to tell whether it is mourning or singing.

Does the silence of an insect mean that it is happy? Does it shout loudly to scare off the enemy? If the scarab and cicada yell at danger, why doesn't the weaver girl yell at danger anymore?

In short, it is not clear why it is called an insect.

How insects listen to external sounds is a mystery. Are insects the same as the sounds we hear? Are insects also happy with the sound we call music? Although I couldn't find all the answers through experiments, I did some.

One of my readers, attracted by the small animals I described, specially sent me a music box from Geneva, hoping that I could use it in the insect hearing test. Later, I really used it. I wrote this experiment to thank the readers who sent me a true feeling.

This music box can play several songs repeatedly, and the sound is very crisp and pleasant. I think this should attract some insect listeners. I think the most beautiful music is a passage called "The Bell of Gona City". Can I use this music to attract beetles, longicorn beetles or crickets?

From the beginning of the longicorn beetle, a male longicorn beetle was seen courting a female longicorn beetle from a distance. Its tentacles are held high, reaching forward, and its whole body is motionless, as if whispering: "What do you think of me, am I worthy of you?" At this moment, the soft music of "Gona City Clock" sounded, and Ding Dong was jingling. Deep in thought, the insects are still the same, even the tentacles and sensitive hearing organs are motionless. A few days later, I tried at another time, but it still didn't work. There is no sign that it noticed the sudden music.

The same is true of the experiment of pine scarab. What was the initial state of a pair of fans on the antenna, and then what was the state? Cricket's fine whiskers should easily recognize the sound waves and swing, but after I played the music, the result was still the same. Three subjects, one result, are indifferent to the way I express my feelings.

Someone has recorded such a thing: cicadas on the tree will not stop singing because of the rumble of guns under the tree, but they will still sing loudly; Spiders busy weaving webs are still trying to weave webs, ignoring noisy crowds and crackling firecrackers. Now, in the face of the melodious "Gona City Bell", the worm turned a deaf ear. Can we conclude that insects are deaf? No, it's better to leave some room.

I think these experiments can only show that the hearing of insects is different from ours, just as the compound eye vision of insects is different from that of human beings. Just like a sensitive microphone can hear (if the machine can also use the word "listen") the subtle sound that our ears can't hear and amplify it, but the microphone can't hear the loud sound. If the noise is too loud, the machine will be damaged if only some noise is released. What about insect hearing organs that are much thinner than microphones? The auditory organs of insects are unfamiliar with our voices, whether it's nice music or rude shouting. They only listen to the voices in their own world, and the voices outside that world are worthless to them.

At the beginning of July, the male scarab trapped in the barbed wire began to retreat to the corner, sometimes drilling into the soil and slowly dying of old age. Female insects are busy laying eggs. They dig with an ovipositor at the end of their abdomen like plows, and then climb into the dug pit, sometimes side by side, sometimes side by side, and begin to lay eggs. Each pine beetle lays about 20 eggs and is buried in a pit the size of a pea. It's like planting seeds. After the egg is laid, the female leaves it alone.

This reminds me of the African plant-peanuts. After the peanut blossoms, the flowers drill into the soil, where they bear fruit and the regenerated roots of the fruit germinate. There is also a wild pea in my hometown, and there are two kinds of pods. A pod on the ground and a pod in the soil can take root and sprout. As long as the soil keeps a certain humidity, the offspring of peanuts and wild peas can reproduce and grow. The care of these two plants for their offspring is no different from that of scarabs.

There are some species of gluttonous rhizomes or crop rhizomes in Scarabalaceae, which do great harm to agriculture. And the harm of pine scarab, in my opinion, is not a disaster. It is enough for its larvae to eat rotten leaves and rotten wood. Adults just chew pine needles and never greedy. If I were the owner of the pine forest, I wouldn't care too much about the small losses it caused. Dense pine trees ate some leaves and dropped some pine needles, which was no big deal. Don't disturb it! It is an ornament of summer dusk and a beautiful jewel embedded in the sky on the day of summer solstice.