Systematics & Phylogenetics

Systematics is an umbrella science that spans the disciplines of taxonomy, morphology, biogeography, evolution and phylogenetics among others. As such, it is essentially the study of biodiversity.

My own research centers on the use of DNA sequences and morphological traits to reconstruct the macro-evolutionary history (phylogeny) of select plant groups, especially in or among groups such as the spiderworts, grasses, palms, and their relatives. These phylogenies are then used to (1) fix taxonomic and nomenclatural problems, (2) infer the macro-evolutionary history of morphological and ecological traits, (3) determine rates of speciation, and (4) identify the causal agents or correlates of speciation.

Fieldwork is an important component of my research. My recent studies in the Commelinaceae (spiderwort family) and Restionaceae (African Reeds, Australian Rushes) have required field collections in Central and South America, as well as southern Africa.

Left: Phylogeny of Geogenanthus mapped onto geographical space (phylogeny from Hardy 2001). This phylogeny is the basis for the description of two new species in the genus (Hardy & Faden, in prep.).

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Selected Publications on This Topic:


Warren BH, FT Bakker, DU Bellstedt, B Bytebier, R Claßen-Bockhoff, LL Dreyer, D Edwards, F Forest, C Galley, CR Hardy, HP Linder, AM Muasya, K Mummenhoff, KC Oberlander, M Quint, JE Richardson, V Savolainen, BD Schrire, T van der Niet, GA Verboom, C Yesson, JA Hawkins (2011) Consistent phenological shifts in the making of a biodiversity hotspot: the Cape flora. BMC Evolutionary Biology 11: 39.


Linder HP, CR Hardy (2010) A generic classification of the Restioneae (Restionaceae), southern Africa. Bothalia 40: 1-35.


Hardy CR, P Moline, HP Linder (2008) A Phylogeny for the African Restionaceae, and New Perspectives on Morphology's Role in Generating Complete Species Phylogenies for Large Clades. International Journal of Plant Sciences 169: 377-390.


Hardy CR, HP Linder (2007) Phylogeny and historical ecology of Rhodocoma (Restionaceae) from the Cape Floristic Region. Aliso 23: 213-226.


Hardy CR (2006) Reconstructing ancestral ecologies: challenges and possible solutions. Diversity & Distributions 12: 7-19.

Davis JI, G Petersen, O Seberg, DW Stevenson, CR Hardy, MP Simmons, FA Michelangeli, DH Goldman, LM Campbell, CD Specht, JI Cohen (2006) Are mitochondrial genes useful for the analysis of monocot relationships? Taxon 55: 857-870.

Petersen G, O Seberg, JI Davis, D Goldman, DW Stevenson, LM Campbell, FA Michelangeli, CD Specht, MW Chase, MF Fay, JC Pires, JV Freudenstein, CR Hardy, MP Simmons (2006) Mitochondrial data in monocot phylogenetics. Aliso 22: 52-62.


Hardy CR, HP Linder (2005) Intraspecific variability and timing in ancestral ecology reconstruction: A test case from the Cape flora. Systematic Biology 54 (2): 299-316.

Linder HP, CR Hardy (2005) Speciation in the Cape flora: A macroevolutionary and macroecological perspective. Pp. 46-73 in F. T.
Bakker, L. W. Chatrou, B. Gravendeel and P. B. Pelser, eds. Plant species-level systematics: new perspectives on pattern & process. Koeltz, Königstein.

Linder HP, CR Hardy, F Rutschmann (2005) Taxon sampling effects in molecular clock dating: An example from the African Restionaceae. Molecular Phylogenetics & Evolution 35: 569-582.


Hardy CR, RB Faden (2004). Commelinaceae. Pp 425-427 in Smith N, S Mori, A Henderson, DW Stevenson, SV Heald (eds.) Flowering Plants of the Neotropics. Princeton University Press.

Hardy CR, RB Faden (2004) Plowmanianthus, a new genus of Commelinaceae with five new species from tropical America. Systematic Botany 29 (2): 316-333.

Davis JI, DW Stevenson, G Petersen, O Seberg, LM Campbell, JV Freudenstein, DH Goldman, CR Hardy, FA Michelangeli, MP Simmons, CD Specht, F Vergara-Silva, MA Gandolfo (2004) A phylogeny of the monocots, as inferred from rbcL and atpA sequence variation, and a comparison of methods for calculating jackknife and bootstrap values. Systematic Botany 29 (3): 467-510.

Linder HP, CR Hardy (2004) Evolution of the species-rich Cape flora. Philosophical Transactions of the Royal Society of London B 359 (1450): 1623-1632.


Hardy CR, DL Lipscomb, KC Nixon, H Ochoterena (2003) WinClada ver. 1.0, a basic users manual. Available upon request from Kevin C. Nixon, Bailey Hortorium, 462 Mann Library, Cornell University, Ithaca, NY 14853.   2001

Hardy CR (2001) Systematics of Cochliostema, Geogenanthus, and an undescribed genus in the spiderwort family Commelinaceae. Ph.D. Dissertation, Cornell University , Ithaca , NY .  


Stevenson DW, JI Davis, JV Freudenstein, CR Hardy, MP Simmons, CD Specht (2000) A phylogenetic analysis of the monocotyledons based on morphological and molecular character sets, with comments on the placement of Acorus and Hydatellaceae. Pp 17-24 in Wilson KL and DA Morrison (eds.) Monocots: systematics and evolution. CSIRO Publishing: Australia.