Overview
- The study published in PNAS uses more than 1.6 million insects trapped in Costa Rica to generate a local park estimate of roughly 333,000 insect species and then scales that figure to a global total.
- Researchers combined long-term Malaise traps and caterpillar rearing with DNA barcoding that yielded about 54,000 barcode-based groups to measure unseen diversity directly from specimens.
- The team adapted capture–recapture-style statistical estimators from epidemiology and applied an upscaling factor anchored to global tree-species patterns to produce a conservative world range of roughly 14 million to 20 million species.
- Only about 1.2 million to 1.5 million insect species have formal scientific descriptions, a shortfall that the paper says creates a major taxonomic backlog and raises the risk that many species could decline or vanish before they are named.
- The work, published June 29 in Proceedings of the National Academy of Sciences, challenges the long-used ~6 million benchmark, highlights key scaling uncertainties in moving from one park to the globe, and points to a need for faster genetic surveying and more taxonomic resources to guide conservation.