My research focuses on the evolutionary origin of Neotropical rainforests. I integrate paleobotanical and neobotanical studies of plant diversity, morphology, and ecology to understand the origin of angiosperm plant lineages. I am also interested in the paleobiogeographic and paleoclimatic history of the Cenozoic, especially in the Neotropics, North America, and Europe. My work at the Chicago Botanic Garden is the study of mesofossils from the Early Cretaceous (100-120 millions years old) of Mongolia and China. I seek to improve knowledge about the timing of events in seed plant composition and evolution for this period of time. I am very interested in the study of fossil gymnosperms such as Pinaceae, Cupressaceae, and other extinct groups of seed plants.