Founder’s Briefs: An occasional series where Mongabay founder Rhett Ayers Butler shares analysis, perspectives and story summaries.
Long before “biodiversity hotspot” became a conservation cliché, Alwyn Howard Gentry was painstakingly mapping them — one vine, one tree, one tenth-hectare transect at a time.
His early death in 1993 at age 48, in a plane crash in Ecuador alongside famed ornithologist Ted Parker during a Rapid Assessment Program expedition, cut short a career of uncommon brilliance, as Oliver L. Phillips deftly describes in “How Al Gentry Changed Tropical Ecology”, published in the Annals of the Missouri Botanical Garden.
Three decades on, Gentry’s methods still undergird much of tropical ecology. He did not merely advance a discipline — he altered how we see the world’s richest ecosystems, and in doing so, widened the circle of who gets to understand, and protect, them.
Trained as a taxonomist, Gentry possessed a rare combination of encyclopedic botanical knowledge and an irrepressible appetite for data. The traditional study of tropical forests was hampered by two conundrums: an overwhelming diversity of species, and the frustrating scarcity of flowers, the primary means of identifying plants. Gentry circumvented both with innovation: identifying trees and lianas using so-called “sterile” characters — leaves, bark, latex — rather than waiting for reproductive parts. It was a heretical move to some in botanical circles. It also worked.
This breakthrough laid the foundation for a standardized rapid-inventory protocol using 0.1-hectare (0.25-acre) plots. He completed 226 such transects across the world’s forests, from Amazonia and the Andes to Madagascar and Malaysia. What he produced was more than just a mountain of specimens; it was a coherent, replicable methodology that democratized field botany and allowed for comparisons across sites, regions and biomes. Today’s planetary-scale forest databases, such as ForestPlots.net and RAINFOR, are built on Gentry’s design principles.
His legacy is not just methodological. Gentry revealed that western Amazonia and the adjacent Andean foothills harbor the world’s greatest diversity of woody plants. He showed how rainfall and soil drive species composition, how lianas and epiphytes contribute to forest complexity, and why even degraded or nutrient-poor forests matter for conservation. He brought quantitative rigor to ethnobotany, helped inspire the global conservation “hotspots” model, and mentored a generation of Latin American botanists. His 1993 Field Guide to the Families and Genera of Woody Plants of Northwest South America, known reverently as “Gentry’s Bible,” remains an indispensable tool for field scientists.
Gentry often traveled with nothing but a plant press and a fierce determination to get things done. Yet, despite his intensity, he was known for generosity with colleagues, humility in discovery, and a deep, if quietly expressed, reverence for the forests he studied.
“Science,” he once said, “starts with seeing.” Thanks to Gentry, generations of ecologists now see not just trees, but the complex, fragile and vital systems they comprise. That may be his greatest legacy of all.
Banner image: Alwyn Gentry at work in Ecuador. Image courtesy of Randall Hyman.
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