Kowalski Elizabeth A, Dilcher David L
Florida Museum of Natural History, University of Florida, P.O. Box 117800, Gainesville 32611, USA.
Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):167-70. doi: 10.1073/pnas.232693599. Epub 2002 Dec 19.
Floras of predominantly wet-soil environments show a greater than expected proportion of toothed leaves, affecting the outcome of leaf physiognomically based temperature estimates. New analyses of foliar physiognomy of plants growing in predominantly wet soils in modern forests suggest that current methods of inferring paleotemperatures from fossil floras yield underestimates of 2.5-10 degrees C. The changes we propose bring terrestrial paleotemperature estimates into agreement with temperatures inferred from other biological and geological proxies and strengthen the use of leaf physiognomy as a method for climate reconstruction.