The causes of locust plagues are complex and not fully understood by human scientists. Based on the available information and results, locust plagues are mainly caused by drought from an environmental point of view.

Drought years are prone to locust plagues, and the ancient Chinese have summed up this law, the so-called "ten droughts and nine locusts". The main reason for this phenomenon is that the arid environment has many benefits for locust reproduction, growth and survival.

On the one hand, because locusts lay their eggs in the soil, in drought years, due to the drop in water level, the soil becomes more solid, the water content decreases (the water content is 10%~20% when they are most suitable for spawning) and the ground vegetation is sparse, the number of eggs laid by locusts increases greatly, and it can reach 4000-5000 eggs per square meter of soil, and there are 50-80 eggs in each egg mass, that is, 200,000-400,000 eggs per square meter.

Second, in dry years, rivers and lakes shrink and low-lying areas are exposed, providing more suitable places for locusts to lay eggs.

On the other hand, plants grown in arid environments have a lower water content, and locusts feed on them, growing faster and having higher fertility.

Recently, the climate around Dongyang City has been relatively arid.

After the beginning of spring, although the land on both sides of the river ushered in a short spring rain, allowing the plants to begin to sprout, the rainfall was not large. In addition, although the winter is cold, there are no snowflakes falling at all, and the whole land is now in a relatively arid state, which is suitable for the mass reproduction and rapid growth of locusts.

When locust numbers are insufficient, locusts are usually timid and prefer to live alone, so the damage is limited. But they sometimes change their habits and like to live in groups, and eventually gather in large numbers and migrate en masse, forming a formidable plague of locusts.

This is due to the fact that when locusts are touched in a certain part of their hind legs, they change their habit of solitary behavior and become social preference.

Scientists at the University of Oxford have experimented with solitary desert locusts, repeatedly touching multiple parts of the locust's body to see if there are certain tactile factors that cause the locusts to change their habits. It was found that when a part of the locust's hind legs was stimulated, they suddenly became gregarious, but touching other parts of the body such as the antennae, mouth or abdomen did not. Scientists believe that the contact of locusts that occasionally gather on the hind legs of a certain natural environment may cause them to change their habits and start living in swarms, and their members will increase in large numbers in the same way, resulting in locust plagues.

Locusts form orderly local swarms and have the ability to move in unison, enter the habitats of their neighbors, and add more and more locusts to them, eventually becoming huge locust swarms.

Scientists have placed the growing swarms of locusts in a circular field, recorded their behavior, and used computer software to track their movements.

At moderate densities (25 to 62 locusts per square meter), the locusts line up in rows and begin to move in the same direction, or even change direction abruptly in unison. In the experiment, when the number of locusts per square meter exceeded 74, the orderly locust swarm stopped changing direction and continued to advance in the same direction for 8 hours. These observations confirm the FAO definition of a colony of locust nymphs, at which swarms tend to cross the "tipping point" and trigger a locust infestation.

Ants are no strangers to locust plagues, and there are always one or two locust plagues in the local area in ten years, and in terms of the lifespan of the queen and male, they will encounter an average of one or two locust plagues in their lifetimes, and leave unforgettable memories.

If for humans, locust plague simply means that crops are damaged, food is not harvested, and famine is caused. Ants are more afraid of locust plagues.

Migratory swarms of locusts can eat up all the vegetation in one place, covering the entire flat land on both sides of a large river.

When the locusts have eaten all the plants they can eat, other insects that have lost their food are starved to death or forced to move away. But ants can't leave the nest and fly high, when there is no prey and no plants, the ants lose their food source and will starve to death en masse.

According to the recollection of the older male ants, in the most miserable years, as many as eighty percent of the people of the kingdom were starved to death, and those who survived had to live on the corpses of their companions, until a few months later a new batch of plants grew and new arthropods appeared to alleviate the famine.

Another horror of locust plagues for ants is that locusts aren't just vegetarians!

Vegetarianism here is literal!

Although locusts feed on vegetation, they also eat meat when food is scarce and are extremely aggressive.

Observers in Xinjiang have seen about 40 locusts gnawing on the remnants of meat on the paws of chickens discarded by humans. Observers have also confirmed that the captured locusts, which had not been fed for several days, attacked and ate the spiders that were nearby.

In this world, locusts have few natural predators, and swarms of locusts are almost invincible. Imagine an attack by hundreds of millions of wolves who are not afraid of death, even if the human army with modern weapons has to deal with it. And locusts are so numerous, fearless of death and able to fly to the sky, but ants have no advanced weapons, only flesh and blood.

When the locusts are so numerous that the local vegetation cannot satisfy the appetites of these greedy bugs, and the locust swarms have not yet begun to migrate, the locusts hunt other arthropods.

Even ants, which are also known for their collective strength, cannot resist the predation of these locust swarms. The locust swarm can easily break up the dense formation of the ants and feast on it.

Even if the ants hide underground, the locusts will dig into the earth and attack, and nothing can stop these monsters who are bent on eating and eating.

Located in the northern part of the hills, Dongyang Castle and its surrounding areas are relatively drier and have always been the source of locust plagues, and have been devastated every time.

It is precisely for this reason that the big-headed ant kingdom did not devote itself to developing into the southern hilly areas, but bothered to expand northward, fighting endlessly across the big river and the paving ant barbarian country.

The painful memories of the locust plague have been passed down from generation to generation by the males, and the older males at the "transfer station" have already sensed the signs of the locust plague and are eager to report it to the protagonist.

Ants have never been able to stop locust outbreaks, and older males have only done their part.

After the locust plague, it is difficult to say how many ants will survive in the entire big-headed ant kingdom, but in the small and poorly defended "transit station", the elderly male ant and his team are trapped in the locust plague hinterland, and there is almost no chance of survival.

But as long as the protagonist doesn't give the order, these dutiful ants will never leave this dangerous place.