Adil GÜNER, Vehbi ESER - optima

IS THERE REALLY A CONFLICT BETWEEN TRADITIONAL AND
MOLECULAR SYSTEMATICS?
Tod F. STUESSY
University of Vienna, Department of Systematic & Evolutionary Botany, Vienna, Austria tod.stuessy@univie.ac.at
Sequencing of the DNA molecule has had numerous impacts on human society, and this
influence continues to widen. Unlocking the hereditary information contained within genes as
well as understanding roles of intergenic regions offers potentials for revealing the basis of the
human condition, amelioration or elimination of disease, regulation of controlled substances, and
many other uses. Within biology, unraveling the genomes of selected organisms has resulted in
new insights on numerous aspects of cell biology, including developmental patterns, and also
evolutionary relationships. It is this last aspect that has come powerfully into systematic biology.
For the first time, we now have a quantitative yardstick that enables us to measure genetic
similarity (or difference) between any two organisms, no matter at what level of the taxonomic
hierarchy. This approach has unleashed thousands of sequencing projects that utilize selected
genes or intergenic regions from the nucleus and/or organelles, often in combination, in consort
with tree-building algorithms that provide more precise views of relationships. Due to these
exciting potentials, many of the new jobs in plant systematics have now been oriented toward
persons with DNA expertise. This has threatened the training of fundamental aspects of our field,
especially monography, for the next generation of workers. This lack has substantial
implications because the monograph is where new hypotheses of relationships are proposed that
can be subsequently tested by DNA data. Without more of the former, eventually there will be
none of the latter. Monography and DNA investigations, therefore, must go hand-in-hand for a
more robust approach to estimating evolutionary relationships. Furthermore, for the study of
many biological questions, such as evolution of characters, origin of adaptations, and coevolutionary
patterns, knowledge of the whole organism will require personal field and
herbarium expertise that can be enhanced, rather than substituted, by DNA information.
Keywords: evolution, DNA data, monography, phylogenetics.
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