1. Chicago Botanic Garden Glencoe 60022 Illinois USA
2. Earth Sciences, Negaunee Integrative Research Center Field Museum of Natural History Chicago 60605 Illinois USA
3. State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment Chinese Academy of Sciences Nanjing 210008 People's Republic of China
4. Institute of Paleontology and Geology Mongolian Academy of Sciences, Ulaanbaatar‐51 Mongolia
5. Oak Spring Garden Foundation Upperville 20184 Virginia USA
6. Yale School of the Environment Yale University New Haven 06511 Connecticut USA