When the sun comes out in the mountains of central Mexico, hundreds of millions of tiny, orange monarch butterflies fill the skies.
To see the monarchs in their element, we rode through the forest of Michoacán, more than 11,000 feet above sea level, with Homero Aridjis, who grew up in the mountains. Aridjis has been visiting the butterflies each winter for 60 years.
It's not just the sheer number of butterflies that is astonishing, it is the density of them in the landscape. It is as if...Full Story