One-third of the world's insects are endangered, and the populations of 40 percent are in a rapid decline.  It's pointing to a "catastrophic collapse of nature's ecosystems".

A new study says these die-offs are happening because of human activity - insects are losing their habitats to farming and urbanization, the use of pesticides, and climate change. 

"Unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades," the study's authors wrote, "The repercussions this will have for the planet's ecosystems are catastrophic to say the least."

The importance of insects in the food chain cannot be overstated.  Some insects are often the food source of higher animals that wind up on our dinner plates.  Others such as bees and butterflies also perform a crucial role in fruit, vegetable, and nut production.  

The researchers say it is "shocking" that insects populations have been decreasing 2.5 percent a year for the past.  If this trend continues unabated, the Earth may not have any insects at all by 2119.

"In 10 years you will have a quarter less, in 50 years only half left and in 100 years you will have none," said University of Sydney researcher Francisco Sanchez-Bayo, a study coauthor.  "If insect species losses cannot be halted, this will have catastrophic consequences for both the planet's ecosystems and for the survival of mankind."