If you travel from the alpine zone to the lowland tropics, more than just the climate will change. Species composition follows changing environments: there is a reason why a Cyathea tree fern doesn’t live in Colorado but does live in Costa Rica. (Note of course that many millions of years ago, when the earth was…

The sound of a rattlesnake is unmistakable once you’ve heard it once. But this sound wasn’t on my mind when I almost stepped on one a few weekends ago. I was in the Santa Rita mountains of southern Arizona. The highest peak, Mt. Wrightson, looms 7000 feet above the Tucson basin. In late March, mountaintops…

(Re-blogged from a piece I wrote for the White House) My great-grandfather immigrated to the United States from China in 1915, at the age of 11. He soon became the owner of a corner grocery store in Tucson, Arizona, and stayed in the community for decades. Now, almost a century later, I find myself living…

I was honored yesterday to speak at the White House about my work with the University of Arizona’s Sky School. We are a residential outdoor science school located in the heart of the Coronado National Forest. Our mission is to connect K-12 students to science and environment, and so inspire the next generation of conservation…