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December 13, 2019

Rare Finds

New NSF-funded University of Arizona research investigates what proportion of the world's land plants are exceedingly rare, where they're found and how location might put them at risk of human development and a changing climate.

Credit: National Science Foundation/Karson Productions

Rare finds.

I'm Bob Karson with the Discovery Files, from the National Science Foundation.

Ten years ago, thirty-five researchers set out to take 'inventory' of just how many land plant species are on the planet. It resulted in the largest dataset of botanical biodiversity ever created -- gathered from 20 million actual observations. Total unique land plant species documented: almost 435,000.

New research led by the University of Arizona found that nearly 40 percent of those are exceedingly rare -- observed and recorded less than five times. Most tend to be clustered in a handful of areas, such as the northern Andes, Costa Rica, South Africa, Madagascar and Southeast Asia. Places where the climate has been stable since the end of the Ice Age. (Sound effect: sounds of human activity…traffic) Now these regions are projected to be disproportionately affected by climate change, and by increasing human activity -- agriculture, clearing, building cities and towns.

The researchers say if nothing is done, there will be a significant reduction in diversity -- mainly in these rarest of species -- because their low numbers put them most at risk for extinction. The team emphasizes the need for strategic conservation to protect these 'cradles of biodiversity.'

Plans for plants on a changing planet.

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