According to the first global scientific review, insects have never been so close to extinction, with one prediction seeing the total disappearance of arthropod life in less than a century.
With an extinction rate almost 8 times faster than mammals, birds and reptiles, more than 40% of insect species are declining and a third are in danger of disappearing completely from the planet.
Currently insects are in a progression of decrease of 2.5% per year. The possible mass extinction can lead to the collapse of basically all the Earth's ecosystems.
The main causes of the phenomenon can be segmented in the use of agrochemicals (the extreme use of pesticides) and the increasing increase in the global temperature, caused by climatic changes.
The death of insects would cause a chain reaction, since countless species of reptiles and birds simply would not have to feed. The most likely is death by starvation.
And even though the number of species that can adapt to the insect lack is increasing, the growth is very slow.
The study, published by the scientific journal Biological Conservation, can be read here: https://www.sciencedirect.com/science/article/pii/S0006320718313636?via%3Dihub