The Monarch butterfly is headed to rapid extinction in the eastern US, reports Scott K. Johnson, because its complex ecosystem continues to collapse.
…humans are responsible. The life cycle of the monarch is tightly linked with the milkweed plant. Females lay almost all of their eggs on these plants, and the larvae happily munch on them when they hatch. Milkweed tends to pop up in areas where the soil has been disturbed, like farm fields.
As with other weeds, farmers have long tried to keep milkweed from growing amidst (and competing with) their crops. But the introduction of genetically modified corn and soybeans that could survive being sprayed by the herbicide glyphosate (better known by its original trade name "Roundup") suddenly gave farmers a more effective way to clear plants like milkweed.
Got a yard? It's easy to plant milkweed: meet Sedgewick the Monarch Caterpillar—and find out what you can do to save his species