The Changing Paradigm of Angiosperm Systematics: Symbiosis of Morphology and Molecules*

The past half-century has witnessed impressive advances in floristics, incorporation of new comparative data, and methods of phylogeny reconstruction and classification. Innovations in use of molecular data, tree-building algorithms, and statistical evaluations have changed the field of systematics. Rapidly accumulating DNA sequences from chloroplast, nuclear and mitochondrial genomes have provided new informative sets of data. The most significant developments of the last two decades have been the introduction of a truly evolutionary approach through use of cladistic methods, determination of new relationships based on molecular data, and the application of systematics to the problems of biodiversity conservation. In addition to the employment of new DNA data, there has been integration of data from morphology, anatomy, embryology, palynology, reproductive biology, cytology and phytochemistry. DNA barcodes hold the promise to facilitate rapid assessments of species richness in particular geographic regions or taxonomic groups, aid species delimitation, and speed up identification of cryptic species. But there is a continued need for carefully curated DNA databases from specimens correctly identified by specialist taxonomists. The future has been envisioned to be an interactive “cybertaxonomy” with dynamic online description and publication of new species. With the rich biological resources in India and the many excellent taxonomists who are intimately familiar with the regional floras and interesting systematic questions, more molecular systematic studies by the Indian taxonomists should advance our understanding of the tree of life at the global scale and offer opportunities to address many new evolutionary questions.