Monarch butterfly migrations are a spectacle — and a key indicator of ecosystem health #TEDTalks

When monarch butterflies migrate, they produce one of the most iconic wildlife spectacles in the world — and provide us with an important indicator of ecological health, says photographer Jaime Rojo. Telling a story about our relationship to the natural world, he shares his experience photographing these mesmerizing insects deep in their remote mountain habitats in Mexico, diving into the latest research into the mysteries of their multi-thousand-mile journey and sharing how each of us can join