Professor Leo Hickey passed away in February of 2013. Please see his home page for a remembrance.
Mailing address: PO Box 208109, New Haven CT 06520-8109
Street address: 210 Whitney Ave., New Haven CT 06511
Leo Hickey passed away in February 2013. For a remembrance click here
My research centers on reconstructing the evolutionary history of the flowering plants through the coordinated investigation of their comparative morphology and their fossil record. Besides my interest in the sequence of change in flowering plant relationships and their characteristics, I also seek to elucidate the ecological- adaptive factors that have operated to produce the vegetation of today. Much of this effort has involved the development of rigorous methods of identifying the leaves of flowering plants because, even though fossil leaf impressions are the most abundant of megafossil plant remains, they have been extensively misidentified. An especially important part of my research has been the recognition and description of leaf architectural features having systematic significance and a survey of their distribution in over 450 families of living flowering plants.
Paralleling this has been my emphasis on the recognition of ancient plant communities and their environmental parameters, based not only on an interpretation of the fossil plants themselves but on a concommitant analysis of their sedimentary and stratigraphic context. We can now track specific plant communities over significant periods of geologic time (15-30 million years) to determine such things as comparative replacement rate of species or to correlate changes in plant composition and diversity with changes in climate, tectonic regime, sedimentology or the fauna. This has led me to concentrate on times of especially rapid floristic change such as at the appearance of the flowering plants in the early Cretaceous and the mass extinction that terminated the Mesozoic. My work on late Cretaceous and early Tertiary terrestrial strata of the Rocky Mountains and Great Plains of the United States provides evidence on the response of plants to the accumulating stresses of mountain building and climatic changes. On the other hand, data from rocks in the Canadian High Arctic give a look at plant adaptation in a unique environment that alternated between nearly frost-free to cold-temperate conditions during the late Cretaceous to early Miocene. Ultimately, I hope that such approaches will help to explain the reasons for the overwhelming diversity of the flowering plants and the historic consequences that the evolution of this group has had on the earth and its biosphere.