Tuesday, we’re telling the story of the incredible life and work of naturalist Alexander von Humboldt. At the turn of the 19th century, Humboldt trekked across Latin America, exploring rain forests, mapping rivers, and climbing volcanoes. The journey led him to a groundbreaking vision of nature and a prediction of human-induced climate change. Doug’s guest is historian Andrea Wulf, whose new book combines biography and science to remember the man she calls the father of the environmental