The hunting party marched in a hurry, but it was not easy to advance with a large pile of pieces of meat.

All the worker ants hold the meat with their large jaws, and in groups of three to five, they form a ball around the meat and move forward slowly.

The slightest obstacle on the road can be a serious challenge. Several teams fell down a steep slope on one of the roads, and then hurriedly retrieved the pieces of meat and continued the climb.

The soldier ants also began to join the carrying team, and with the joint efforts of the entire hunting team, the group finally arrived at the "transit station" at sunset.

This "staging station" is a material transfer center established by the protagonist during his expedition to the hills, and is now guarded by only one team, including twenty soldier ants and thirty worker ants, commanded by an elderly retired male ant.

After arriving at the "transit station" with the hunting team, Nobita went to visit the elderly male ants stationed here according to the custom of male ants.

As soon as I talked to the older male ants, I realized that something big had happened near the "transfer station"!

The older male ant said that he sent a messenger to "Dongyang City" the day before yesterday to report to the protagonist about the recent changes near the "transit station", but he never waited for the messenger to return, he was worried that the messenger had an accident on the way and failed to deliver the message or send the reply back.

This kind of thing is not uncommon, and the ant messengers who act alone are not very capable of self-preservation, and although they mainly advance on the ant path, they will occasionally encounter fierce insect attacks.

As is customary, after believing that the messenger may not have completed the mission, the sender will send a new messenger after waiting for a certain amount of time without receiving a reply, depending on the distance of the journey.

The elder male ant originally planned to send a messenger to "Dongyang City" the next day, but it happened that Nobita and his party were going to leave tomorrow, so the older male ant asked Nobita and his party to deliver the message on their behalf.

The situation that the older male ants need to report is urgent - there are a large number of locusts near the "transfer station"!

- I'm the dividing line -

Locusts in a broad sense, commonly known as "grasshoppers", belong to the order Orthoptera, including grasshoppers, grasshoppers, and locusts, with more than 10,000 species in the world, distributed in the vast tropical and temperate grasslands and desert areas. Locusts mainly include flying locusts and earth locusts, and the East Asian flying locusts and Asian flying locusts are common in the areas on both sides of the great rivers.

Among the adults of the East Asian locust, the male adults are between 35.5 and 41.5 mm long, and the female adults are between 39.5 and 51.2 mm long. Locusts are usually green or yellowish brown in color, and often vary depending on environmental factors. The face is vertical, and the antennae are pale yellow. The dorsal plate of the prothorax is well developed, the scattered type is slightly curved when viewed from the side, the group type is slightly concave, and there are often dark longitudinal stripes on both sides. The forewings are narrow and long, often beyond the middle of the tibial segment of the hindfoot, with brown and dark markings, and the group type is darker. The hindwings are colorless and transparent. The social form sometimes has 2 inconspicuous dark streaks on the upper side of the hind leg segments, and the dispersed form is often absent or inconspicuous. The tibiae of the hind foot are usually orange-red, the group type is slightly lighter, and there are usually 10~11 spines along the outer margin.

Locusts are generally facultative diapause insects, mostly overwintering in oocysts in the soil, and only a few species such as the Japanese yellow locust and the short-legged locust overwinter as adults.

The annual effective accumulated temperature, food, light and growth and development of locusts at different stages in different regions will affect the number of locusts in different generations. For example, the Asian locust generally occurs in 1 generation in 1 year, the East Asian locust in warm areas is 2 generations, even 3 generations or incomplete 3 generations, and in tropical areas it can reach 4~5 generations.

Adult locusts and locusts are nocturnal and nocturnal, with no obvious phototaxis. When the density of flying locusts is large, due to mutual sensation and the formation of conditioned reflexes, intensified activities, locusts are easy to form swarms, dormant, crowded, and then jump in a certain direction to migrate in a group, this is the locust plague.

The locust plague is a disaster for the vegetation in the affected area. Adult locusts have the same feeding habits as locusts, both are herbivorous, and the adult stage has strong nutritional supplementation, accounting for more than 75% of the total food in a lifetime. They bite the leaves and buds of plants with chewing mouthparts, and in severe cases, they eat up the leaves and buds of large areas of plants, causing an ecological crisis.

Some locust species are oligophagous pests, such as the East Asian locust, which feeds only on grasses and sedges; Some species are polyphagous, such as the Giant Cushion Locust. In general, locusts are the most preferable to weeds such as reeds, barnyard grass and red grass (Ogi).

When the season is dry, locusts are more voracious, and a large amount of food is excreted from the body without being fully digested, so as to obtain a large amount of water from it to supply physiological and metabolic needs, thus increasing the degree of harm to plants.

Once a locust plague breaks out, it is extremely harmful.

Although locusts are an important part of the ecosystem, many harmful locust species can cause varying degrees of harm to the natural world.

Taking the protagonist's original world as an example, there are more than 10,000 species of locusts in the world, of which about 300 species can cause locust plagues, and locusts can occur in the world except for Antarctica and Eurasia north of 550 north latitude.

The area of locusts in the world is 46.8 million square kilometers every year, and one-eighth of the world's population is regularly affected by locust plagues.

There are also more than 1,000 species of locusts known in China, of which about 60 species can cause harm. According to the records of China's historical books for thousands of years, the locusts that cause devastating disasters in agriculture are mainly flying locusts, and it is believed that drought has the greatest chance rate or correlation with the occurrence of flying locusts in the same year, followed by drought in the previous year and first flood and then drought, grasshoppers are in patches; Locust disasters and floods and droughts often occur one after another, alternating with each other, and have always been the three major natural disasters that seriously threaten China's agricultural production and affect people's livelihood.

Since the 80s, due to the impact of abnormal global climate change, the disrepair or improper construction of some water conservancy projects, and the sudden change of agricultural ecology and environment, the East Asian locust has occurred frequently in the Huang-Huai-Hai region and the southwest of Hainan Island, seriously threatening agricultural production.

During the 12 years from 1985~1996, East Asian locusts occurred in the Yellow River beach, Hainan Island, Tianjin and other locust areas year after year. In the autumn of 1985, after eating up more than 100,000 acres of reed leaves and hundreds of acres of corn ears, the high-density swarm of East Asian flying locusts in Beidagang, Tianjin, took off and moved south at noon on September 20, and the locust swarm was about 30 kilometers wide from east to west, and landed in five counties of Cangxian, Huanghua, Haixing, Yanshan and Mengcun in Hebei Province and two farms in Dagang, Zhongjie and Dagang, covering an area of 2.5 million mu. This is the first time since the founding of the People's Republic of China that the social East Asian locusts have migrated across provinces.

In 1998, the summer locust of the East Asian locust occurred in eight provinces, including Shandong, Henan, Hebei and Tianjin. In 1999, the summer locusts of the East Asian locust occurred again in nine provinces, including Shandong, Henan, Hebei and Tianjin. Locusts ravaged Henan again, and the density of locusts in some areas reached more than 4,000 per square meter, which was unprecedented in Henan in 25 years.

In 1983-1984, 1986 and 1987, the Tacheng area of Xinjiang was affected by the swarm-living Asian locusts, affecting an area of 30.05 million mu, with a density of tens of thousands of locusts per square meter in the Altay area of Tacheng.

From 1846 to 1857, locust plagues occurred in Tibet for 12 consecutive years, affecting 18 regions.