The World

The Tangled Web of Montana Spiders

Eensy, weensy spiders are thriving on hardy invasive plants in the hills of Montana. But as they eat more insects, they’re throwing off the balance of the region’s ecosystem.

As invasive plants take root and spread in the grasslands of Missoula, Montana, a tiny native spider is flourishing on the plants and helping wreak havoc on the ecosystem. Producer Ari Daniel Shapiro met with a scientist who is monitoring the transformation and trying to keep the cascade of events in check.