Professor of Geology & Geophysics and Biology
Paleobotany
Current Research:
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.
Classes Taught:
Stratigraphy
Stratigraphic Principles & Applications
Applied Stratigraphy
Recent Publications:
Hickey, L.J., 1996. Paleobotany, Geotimes, v 41(2), 29-30.
Hickey, L.J. and Taylor, D.W., 1996, Origin of the angiosperm flower. In, (Eds.), Taylor, D.W. and Hickey, L.J. Flowering Plant Origin, Evolution, and Phylogeny. Chapman & Hall, 176-231.
Taylor, D.W. and Hickey, L.J. (Eds.), 1996, Flowering Plant Origin, Evolution and Phylogeny. Chapman & Hall, 403.
Taylor, D.W. and Hickey, L.J., 1996, Evidence for, and implications of an herbaceous origin for angiosperms. In, (Eds.) Taylor, D.W. and Hickey, L.J., Flowering Plant Origin, Evolution and Phylogeny. Chapman & Hall, p. 232-266.
Wing, S.L., Alroy, J. and Hickey, L.J., 1995, Plant and mammal diversity in the Paleocene to Early Eocene of the Bighorn Basin. Palaeogeography, Paleaoclimatology, Palaeoecology, v 115, 117-155.
Smith, U.R., and Hickey, L.J., 1994, A capsular fruit from the latest Cretaceous of the Western Interior United States. American Journal of Botany (Abstracts) v 81(6), 102-103. (Abstract)
Moldowan, J.M., Huizinga, B.J., Dahl, J., Fago, F.J., Taylor, D.W. and Hickey, L.J., 1994, The Molecular fossil record of oleanane and its relationship to angiosperms. Science, v 265, 768-771.
Hickey, L.J. and Klise, L., 1994, Peabody Museum's fossil plants: a tale of three collections. Discovery, v 25, 23-26.
Wing, S.L., Hickey, L.J. & Swisher, C.C., 1993, Late Cretaceous vegetation. Nature v 363, 342-344.
Wing, S.L., and Hickey, L.J., 1992, Paleocene-Eocene floral and climatic change in the Bighorn Basin. Paleontol Society Special Publ, No 6, 316 (Abstract).
Hickey, L.J., 1992, Dragged toward Armageddon: A Changing Paleontological Viewpoint on Catastrophism. AAPG Anuual Convention, Calgary, 55-56 (Abstract).
Hickey, L.J. and McWeeney, L.J., 1992, Letter to Nature. Nature v 356, 295-296.
Hickey, L.J. and Taylor, D.W., 1992, Paleobiology of early angiosperms: evidence from sedimentological associations in the Early Cretaceous Potomac Group of the eastern U.S.A. Proc. 5th North American Paleontological Convention, Chicago. Paleontol Soc Spec Publ, No. 6, 128. (Abstract).
Taylor, D.W., and Hickey, L.J., 1992, Investigation of the terrestrial occurrence and biological source of the petroleum geochemical biomarker oleanane. Paleontol Soc Special Publ, No. 6, 286 (Abstract).
Taylor, D.W., and Hickey, L.J., 1992, Phylogenetic evidence for the herbaceous origin of angiosperms. Pl Syst Evol, 180, 137-156.
Taylor, D.W. and Hickey, L.J., 1991, Carbon isotope ratios in fossil land plants. Am Journal Bot, 78 (6) Suppl. 327, 126 (Abstract).
Johnson, K.R., Hickey, L.J. and Hoover, C.A., (Eds.), 1991, Crossroads of continents: The material culture of Siberia and Alaska. YaleSmithsonian Seminar on Material Culture, Washington and New Haven.
Johnson, K.R. and Hickey, L.J., (1991) 1990, Megafloral change across the Cretaceous-Tertiary boundary, northern Great Plains, USA. In, (Eds.), Sharpton, V.L. and Ward, P.D., Global Catastrophes in Earth History: An interdisciplinary conference on impact, vulcanism, and mass mortality. Geol Soc Am Special Paper, 247, 433-444.
Hickey, L.J. and Taylor, D.W., 1991, The leaf architecture of Ticondendron and the application of foliar characters in discerning its relationships. Annual Missouri Bot Gard, v 78, 105-130.
Hickey, L.J. and Hicks, J.F., 1991, High resolution statigraphy and sedimentology of the Eureka Sound Group (Late Cretaceous-Eocene) at Strand Fiord, Axel Heiberg Island, NWT Canada. Geol Society Am, Abstracts with Programs 23(5), A349. (Abstract).
Hickey, L.J., 1991, The physical and biotic setting of trans-Beringian Cultures. In, (Eds.), Johnson, K.R., Hickey, L.J., and Hoover, C.A., Crossroads of Continents: The Material Culture of Siberia and Alaska. Yale-Smithsonian Seminary on Material Culture, Washington, and New York, 8-10.
Hickey, L.J., 1991, Preliminary report on the flora of the Meeteetse Formation (late Cretaceous) of Wyoming and Montana. Am Journal Bot, 78 (6) Suppl, 297, 115 (Abstract).
Scully, V., Zallinger, R.F., Hickey, L.J. and Ostrom, J.H., 1990, The Great Dinosaur Mural at Yale, "The Age of Reptiles", New York, Harry Abrams, 48.
Taylor, D.W. and Hickey, L.J., 1990, An aptian plant with attached leaves and flowers: Implications for angiosperm origin. Science, v 247, 702-704.
Hickey, L.J. and Taylor, D.W., 1990, The leaf architecture of Ticodendron, from a new family of Fagales, and its relationship to the basal Rosidae based on leaf, wood and reproductive characters. Amer Journal Bot, 77(6) Suppl., 136 (Abstract).
Taylor, D.W. and Hickey, L. J., 1990, A new hypothesis of the morphology the ancestral angiosperm. Amer Journal Bot, 77(6), Suppl., 159 (Abstract).
Hickey, L.J. and Taylor, D.W., 1989, Reexamination of leaf architectural characters of basal angosperms and their heir sister-groups: Implications for the origin and relationships of angiosperms. Am Journal Bot, 76(6) Suppl., 245 (Abstract).
Taylor, D.W. and Hickey, L.J., 1989, An Aptian angiospermous plant: implications for the origin of angiosperms and the monocotdicot divergence. Am Journal Bot, 76(6) Suppl., 174 (Abstract).
Li, H. and Hickey, L.J., 1988, Leaf architecture and systematics of the Hamamelidaceae sensu lato. Acta Phytotaxonomica Sinica, v 26, 96- 110.
Hickey, L.J., Johnson, K.R. and Dawson, M.R., 1988, The Haughton Formation: A post-impact crater fill, Devon Island, NWT, Canada. Meteoritics, v 23, 221-231.
Johnson, K.R. and Hickey, L.J., 1988, Patterns of megafloral change across the Cretaceous-Tertiary boundary in the northern Great Plains and Rocky Mountains. In, Abstracts presented to the Topical Conference Global Catastrophes in Earth History. Lunar and Planetary Institute Contribution, 673, 87 (Abstract).
Ostrom, J.H., Hickey, L.J. and Delevoryas, T., 1987, A Guide to the Rudolph Zallinger Mural The Age of Reptiles in thethe Rudolph Zalinger Mural "The Age of Reptiles" in the Peabody Museum, Yale University. 2d edition, Peabody Museum of Natural History.
Omar, G., Johnson, K.R., Hickey, L.J., Robertson, P.B., Dawson, M.R. and Barnosky, C.W., 1987, Fission-track dating of Haughton Astrobleme and included biota, Devon Island, Canada. Science, v 237, 1603- 1605.
Hickey, L.J., 1986, Summary and implications of the fossil plant record of the Potomac Group. In (Ed.), Broadhead, T.W., Land plants. Notes for a short course. The Paleontological Society, 162-181.
Hickey, L.J., Johnson, K.R. and Yuretich, R.F., 1986, Road Log - Red Lodge, Montana to Clark, Wyoming via Elk Basin and Powell, Wyoming. Field trip through the facies of the Fort Union formation. In (Ed.), Garrison, P.B., Geology of the Beartooth uplift and adjacent basins. Montana Geol Society
and Yellowstone-Bighorn Research Association Joint Field Conference and Symposium, 279-290.
Dawson, M.R., Hickey, L.J. and Johnson, K.R., 1986, Discovery of a Dermopteran skull from the Paleogene of Arctic Canada. National Geographic Research, v 2(1), 112-115.
Dawson, M.R., Hickey, L.J. and West, R.M., 1986, Late Cretaceous and Tertiary terrestrial biota, Canadian Arctic, paleobiogeographic and climatic implications. Geol Society Amer, Abstracts with Programs, 18(4), 285 (Abstract).
Johnson, K.R. and Hickey, L.J., 1986, Floristic and vegetational change across the Cretaceous/Tertiary boundary in the Northern Rocky mountains and Great Plains. Geol Society
Amer, Abstracts with Programs 648. (Abstract).
Address:
Prof. Leo J. Hickey
Yale Geology Dept.
P.O. Box 208109
New Haven, CT 06520-8109
(203)432-5006
leo.hickey@yale.edu
