Research published in January 2025 from Penn State revealed a shocking truth: flies, the world's second most important pollinators, are more vulnerable to climate change than bees—and that threatens chocolate, mangoes, and 72% of global food crops. But almost nobody noticed. Kelly breaks down the study everyone missed, explains why flies lose motor function at temperatures 2.3°C lower than bees, explores what this means for everything from alpine ecosystems to tropical cacao farms, and shares why this billion-dollar crisis isn't getting the attention it deserves.

www.secretpollinators.com

KEY SOURCES

Fly vs. bee thermal tolerance

• López-Uribe, M. M., Appert, M. K., Delgado, A. X., Herrera-Motta, A., et al. (2024). Critical thermal maxima of bee and fly pollinators in tropical and subtropical regions of the Americas. Journal of Melittology. Published November 10, 2024. — CTMax for bees averaged 2.3°C higher than for flies; bees foraging in cooler morning hours showed higher CTMax than afternoon foragers.
• Jones, L. J., Miller, D. A., Schilder, R. J., & López-Uribe, M. M. (2024). Body mass, temperature, and pathogen intensity differentially affect critical thermal maxima and their population-level variation in a solitary bee. Ecology and Evolution, 14(2). DOI: 10.1002/ece3.10945

Flies as crop pollinators

• Rader, R., Cunningham, S. A., Howlett, B. G., & Inouye, D. W. (2020). Non-Bee Insects as Visitors and Pollinators of Crops: Biology, Ecology, and Management. Annual Review of Entomology, 65, 391–407. DOI: 10.1146/annurev-ento-011019-025055 — 105 animal-pollinated crops reviewed; 82 (77%) visited by both bee and non-bee taxa, combined GDP value US$780.8 billion; Syrphidae and Calliphoridae the most frequent non-bee visitors.
• Rader, R., Bartomeus, I., Garibaldi, L. A., et al. (2016). Non-bee insects are important contributors to global crop pollination. PNAS, 113(1), 146–151. DOI: 10.1073/pnas.1517092112 — non-bee insects provided 39% of crop flower visits across 39 field studies.
• Doyle, T., Hawkes, W. L. S., Massy, R., Powney, G. D., Menz, M. H. M., & Wotton, K. R. (2020). Pollination by hoverflies in the Anthropocene. Proceedings of the Royal Society B, 287(1927). DOI: 10.1098/rspb.2020.0508 — Diptera visit 72% of the 105 crops in Rader et al.; hoverflies alone visit 52%; billions of migrant hoverflies move into southern Britain annually.
• Cook, D. F., Voss, S. C., Finch, J. T. D., Rader, R. C., Cook, J. M., & Spurr, C. J. (2020). The role of flies as pollinators of horticultural crops: An Australian case study with worldwide relevance. Insects, 11(6), 341.

Cacao pollination

• USDA Forest Service, Fly Pollination fact sheets. fs.usda.gov

#ClimateChange #Pollinators #Flies #FlyPollinators #SaveTheFlies #Chocolate #ChocolateCrisis #Hoverflies #NativePollinators #ClimateEmergency #FoodSecurity #PollinatorConservation #ClimateAction #Biodiversity #FlyConservation #PollinatorClimateChange #ChocolateProduction #CacaoPollinators #AlpinePollinators #InsectDeclining #HoverflySyrphidae #Blowflies #PollinatorResearch #ClimateImpact #TemperatureTolerance #PennStateResearch #BreakingScience #NewResearch2025 #PollinatorScience #ClimateScience #EnvironmentalResearch