639177 external_news 1600287237 1600287237 A study of fossil pollen samples in North America shows the resilience of plants could be the lowest it's been for 13,000 years. “We find that the retreat of North American glaciers destabilized ecosystems, causing large herbivores—including mammoths, horses, and camels—to struggle for food supplies,” says Jenny McGuire.

]]> 2020-09-15 1278 364801 1275