Prelims: Current events of national and international importance | Environment
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A recent ecological study published in the Proceedings of the National Academy of Sciences (PNAS) has upended structural entomological metrics.
The discovery highlights that over 90% of global insect biodiversity remains entirely unknown.
Instead of attempting to count every bug blindly, researchers focused on Microgastrinae, a highly diverse subfamily of parasitoid wasps.
These wasps lay their eggs inside living caterpillars; the developing larvae consume the host from the inside out before emerging.
The team deployed 15 Malaise traps (specialized tent-like mesh structures designed to catch flying insects) across both undisturbed core zones and modified peripheral zones of the ACG.
They captured a total of 1.63 million tropical insects.
Scientists used DNA barcoding, a molecular technique that sequences a short, standardized fragment of mitochondrial DNA to rapidly identify and differentiate species.
The core Malaise traps alone revealed an astonishing 53,945 distinct insect species.
When combined with specimens bred directly from collected caterpillars, the team cataloged 1,414 distinct species of Microgastrinae wasps within the reserve alone.
The ACG reserve contains between 1,200 and 1,500 tree species.
By comparing this to the world's estimated 73,000 tree species, scaling up the math yielded a preferred global estimate of 20.3 million insect species.
Alternative Checks: The researchers cross-checked this math by scaling against other well-mapped local groups, including amphibians, mammals, and Saturniid (emperor) moths.
These alternative calculations yielded a conservative global range of 14.2 million to 20.3 million species.
The massive gap underscores the severe shortage of specialized taxonomists and the critical need for rapid molecular tools like DNA barcoding.
Human activities, habitat fragmentation, and climate change are causing unprecedented drops in global insect populations.
This study shows we are at risk of losing millions of species before we even discover they exist.
