1. Department of Organismic and Evolutionary Biology and Harvard University Herbaria Harvard University Cambridge MA 02138 USA
2. Department of Biology Teaching and Learning University of Minnesota Minneapolis MN 55108 USA
3. Key Laboratory of Bio‐Resource and Eco‐Environment of Ministry of Education College of Life Sciences Sichuan University Chengdu 610065 China
4. Biota of North America Program 9319 Bracken Lane Chapel Hill NC 27516 USA
5. Institute for Quantitative Social Science Harvard University Cambridge MA 02138 USA