Over the past 40 years, the estimate accepted by experts is that there are about six million species of insects.
The new count is based on genetic information from 1.6 million individual tropical insects, a census of a highly diverse group of parasitoid wasps in the Guanacaste Conservation Area (GCA) of Costa Rica.
The study led by Cornell University (USA) and published by PNAS considers that doubling or tripling the estimated number of insect species “has profound implications for understanding the scale, richness and future of biodiversity on Earth.”
“We cannot protect species if we do not know they exist, so in order to understand the biodiversity of our planet, it is important to know how many there are.”
Laura Melissa Guzmán, from Cornell University and one of the authors of the article.
So far, science has described (named and characterized) around 1.2 million species of insects and it is known that many more remain to be discovered.
The team combined DNA barcoding (a fundamental tool for quickly and efficiently delimiting biological species and facilitating their identification) and a statistical method to revise the estimate of the lower limit of the global number of insect species.
In addition, they used a census of parasitic microgastrin wasps from 15 additional traps and 11,373 specimens raised from approximately 1,500 species of parasitized caterpillars, in order to estimate the real richness of microgastrins in the area.
Recent reports have warned that human activities are causing a massive die-off of insects worldwide, which has been called the ‘insect apocalypse’. The new global estimate of these animals may be a step forward to protect those that remain.
“Our results – Guzmán said – point to a large number of undescribed insects, that is, those that do not yet have a name” and there could be many species in decline that we have not even discovered.”