KAPLAN, DONALD R. Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720. - The science of plant morphology: man bites dogma.
As a scientific discipline plant morphology is exactly 208 years old,
having been originated by Goethe in 1790. It is a discipline that has
largely been Germanic in origin and function. Because it took its
origins from the study of the natural history of plants and the United
States is principally an engineering society, plant morphology in its
pure form never made it to this country. What has been labeled “Plant
Morphology” has served largely as a “handmaiden” for systematics,
using morphological characteristics to carve up diversity into its
systematic subunits. Since the center of gravity of Plant Morphology
as a science are the convergences rather than the homologies in a
phylogenetic sense, the German tradition of Plant Morphology is a
unifying science determining fundamental themes that transcend the
usual systematic boundaries. This paper traces the history of the
science of Plant Morphology through the lineage of its principal
practitioners--Goethe, Hofmeister, Goebel and Troll in order to
indicate the reasons for the directions it took. In order to
demonstrate the principles of Plant Morphology, these concepts are
applied to the interpretation of the morphology of pteridophytic
groups to see whether members of these ancient alliances exhibit basic
principles that are different from those of other vascular plants. In
the process, concepts of megaphyllous vs. microphyllous leaves and
other morphological theories are evaluated as a test of their
validity. From this evaluation it is suggested that all of these
contemporary organismal groups are at an equivalent level of
morphological organization and therefore it is fruitless to seek or
describe their morphology in terms of telomes or telomic levels of
organization.
Key words: Pelton Award, phylogeny, plant morphology