Full Breakdown
New DNA Barcoding Study Suggests Earth Hosts Up to 20 Million Insect Species
7/2/2026, 11:14:20 AM
Revised Global Species Count
A multinational team led by researchers from Cornell University, the University of Kentucky, the University of Colorado, the University of Connecticut, and the University of Plymouth has published a study in *Proceedings of the National Academy of Sciences* that raises the lower bound of global insect diversity from the long-standing estimate of roughly six million species to a range of 14 million–20 million, with some analyses extending the upper bound to 30 million. The estimate is derived from intensive sampling in Costa Rica’s Área de Conservación Guanacaste (ACG), a 169,000-hectare UNESCO World Heritage site.
Background & Context
For four decades the scientific consensus has held that about six million insect species exist worldwide, of which roughly 1.2 million have been formally described. This figure has guided biodiversity assessments, conservation funding, and policy discussions.
Methodology & Data
Researchers deployed 15 core Malaise traps and 15 peripheral traps across ACG, capturing more than 1.6 million insects. DNA barcoding of these specimens identified 53,945–54,000 distinct barcode index numbers (BINs), a proxy for species. Parallel sampling of the parasitoid wasp subfamily Microgastrinae yielded 1,414 observed species; statistical extrapolation (using the Chao estimator) suggested a true local richness of 2,394 ± ~200 species. By scaling the ratio of observed to estimated Microgastrinae to the total insect BINs, the team inferred roughly 333,000 insect species in ACG. A second scaling step compared ACG’s 1,200–1,500 tree species to the global estimate of ?73,000 tree species, producing the global insect range of 14–20 million (conservative) to 30 million (maximum). The authors note that 93–97 % of insect species remain unnamed.
Official Statements & Responses
Corresponding author Laura Melissa Guzman emphasized that “knowing how many species exist is a prerequisite for protection.” Co-author Robert Puschendorf highlighted the difficulty of quantifying diversity and the need for comprehensive inventories. Robert Colwell warned that the sheer volume of undescribed tiny insects dwarfs the catalogued larger taxa. The study’s authors describe their figures as conservative, acknowledging that methodological gaps likely cause underestimation.
Criticism & Limitations
The authors acknowledge that Malaise traps under-sample canopy-dwelling insects and certain taxonomic groups, and that barcode clusters (BINs) are approximations rather than formal species descriptions. Consequently, the global estimate may still be a lower bound.
Why It Matters
If the revised count is accurate, the number of insects at risk from habitat loss, climate change, and pesticide use could be far larger than previously recognized. Conservation strategies that rely on species inventories may be overlooking the majority of insect biodiversity, complicating efforts to address the reported “insect apocalypse.”
Conflicting Reports & Gaps
While most sources converge on a 14–20 million range, one report extends the upper bound to 30 million, reflecting differing scaling assumptions. The study does not provide region-specific estimates beyond ACG, leaving gaps in tropical and temperate biodiversity knowledge.
Verbatim Quotes
- “Diversity is really hard to quantify, but what this new study shows is that we have completely underestimated the insects.” — Dr. Robert Puschendorf, University of Plymouth
- “We cannot protect species if we don’t know that they exist, and so to be able to understand the biodiversity on our planet, it’s important to know how many there are,” — Laura Melissa Guzman, Cornell University
- “Our results point to a large number of undescribed insects, those without a name,” — Laura Melissa Guzman, Cornell University
- “ Colwell notes, “The diversity of tiny, undescribed insects (especially micro-wasps and miniscule flies) — not only in the tropics but everywhere — vastly overwhelms the number of well-known, larger insects familiar to the public.” — Robert Colwell, University of Connecticut
- “Puschendorf noted that it is functionally impossible to protect and manage an ecosystem when conservationists remain blind to the vast majority of its inhabitants.” — Dr. Robert Puschendorf, University of Plymouth
What’s Next
The team calls for expanded DNA-barcoding efforts, especially in forest canopies and under-sampled habitats, and for integrating these data into global biodiversity monitoring frameworks. Funding agencies are urged to prioritize taxonomic discovery to inform conservation policy before further insect declines occur.
