Insects are the most abundant animals on planet Earth. If you were to put them all together into one creepy-crawly mass, they’d outweigh all humanity by a factor of 17.
Insects outweigh all the fish in the oceans and all the livestock munching grass on land. Their abundance, variety (there could be as many as 30 million species), and ubiquity mean insects play a foundational role in food webs and ecosystems: from the bees that pollinate the flowers of food crops like almonds to the termites that recycle dead trees in forests.
Insects are also superlative for another, disturbing reason: They’re vanishing at a rate faster than mammals, fish, amphibians, and reptiles.
“The pace of modern insect extinctions surpasses that of vertebrates by a large margin,” write the authors of an alarming new review in Biological Conservation of the scientific literature on insect populations published in the past 40 years. The state of insect biodiversity, they write, is “dreadful.” And their biomass — the estimated weight of all insects on Earth combined — is dropping by an estimated 2.5 percent every year.
In all, the researchers conclude that as much as 40 percent of all insect species may be endangered over the next several decades. (Caveat: Most of the data was obtained from studies conducted in Europe and North America.) And around 41 percent of all insect species on record have seen population declines in the past decade.
“We estimate the current proportion of insect species in decline … to be twice as high as that of vertebrates, and the pace of local species extinction … eight times higher,” the authors write. “It is evident that we are witnessing the largest [insect] extinction event on Earth since the late Permian and Cretaceous periods.”