California Academy of Sciences - To Explore, Explain, and Protect the Natural World


Curator of Botany
Department of Botany

B.S. University of Michigan (1983). M.S. University of Michigan (1988). Ph.D. Rancho Santa Ana Botanic Garden Program in Botany and Claremont Graduate School (1995). A. W. Mellon Postdoctoral Fellow, Duke University (1995-1996) Assistant Curator, California Academy of Sciences (1996-2001). Associate Curator, California Academy of Sciences (2002-).

Member: American Society of Plant Taxonomists, Botanical Society of America, Society of Systematic Biologists, International Association of Plant Taxonomy, Bay Area Biosystematists

Bruce Bartholomew, Senior Collections Manager

My primary research focuses on the systematics, biogeography, and evolution of members of the flowering plant order Ericales, a group of about 23 plant families that includes many well-known plants such as blueberry, phlox, persimmon, primrose, and tea. Many of the plants in this order are disjunct relicts, which means that they were once (in the Tertiary period) widespread but are now restricted in range to discrete and widely separated areas of the earth due to climate change. These areas include California, southern Europe, eastern North America and eastern Asia. I use a combination of morphological and molecular approaches on ericalean groups to understand their species diversity, evolutionary relationships, and adaptations to particular environments. The patterns of relictualism and speciation elucidated from these studies can eventually lead to a better overall understanding of the effects and significance of climate change on the world's biota.

In collaboration with Frank Almeda (CAS-Botany) and other colleagues, I am currently concentrating on the genus Symplocos (Symplocaceae, the sweetleaf family, ca. 300 species). This clade has an amphi-Pacific tropical disjunction, meaning that it occurs in tropical regions (although with a few temperate outliers) in the Americas and the lands bordering the Pacific Rim, but nowhere else. It is generally assumed that amphi-Pacific tropical disjuncts arrived at their present distributions through migration across high-latitude land bridges in the Tertiary period, when global climate was much warmer than today. This idea is bolstered by Tertiary fossil fruits of Symplocos in North America and especially in Europe, where there appear to have been whole forest ecosystems dominated by Symplocos. A minority opinion holds, however, that these disjuncts can be accounted for by trans-oceanic tropical migration and that fossil sampling artifact has obscured the more widespread nature of these disjuncts.

We are currently testing these ideas in a phylogenetic context by analyzing DNA sequences of Symplocos species from throughout the distribution of the genus. Preliminary results are tending to support a Northern Hemisphere origin for the group with subsequent migration to South America. This pattern has also been found in Styrax (Styracaceae), another member of Ericales. Through international collaboration I am expanding studies on amphi-Pacific tropical disjuncts to include other members of Ericales such as Clethra (Clethraceae) and Gaultheria (Ericaceae, wintergreen) in an attempt to detect general patterns of intercontinental dispersal among these groups.

Within the context of this research I also conduct studies in floristics and taxonomy. I lead a long-term, large-scale survey and inventory of the biota of the Gaoligong Mountains in western Yunnan Province, China. This survey is documenting the land plants, arthropods, vertebrates, and Quaternary vertebrate fauna of this biodiversity "hotspot". Three primary institutes form the primary collaboration in this project: the Kunming Institute of Botany, the Kunming Institute of Zoology, and the CAS. The project is discovering many new species to science and many new records for the region, and also is developing a comprehensive GIS-based data set for use in biogeographical analysis and conservation management strategies for the local government. My colleagues and I are preparing taxonomic treatments of various plant groups based on this research. This complements my past and current monographic studies and taxonomic revisions on Styracaceae and Symplocos (such as treatments for Flora of China, Flora Neotropica, and Flora of North America).

1. Fritsch, P. W. and L. H. Rieseberg. 1992. High outcrossing rates maintain male and hermaphrodite individuals in populations of the flowering plant Datisca glomerata. Nature 359: 633–636. Download PDF


2. Fritsch, P. W. 1992. Scutellaria nervosa (Lamiaceae):  A species of skullcap new to Michigan. Michigan Botanist 31: 37–38. Download PDF


3. Rieseberg, L. H., C. T. Philbrick, P. E. Pack, M. A. Hanson, and P. W. Fritsch. 1993. Inbreeding depression in androdioecious populations of Datisca glomerata (Datiscaceae). American Journal of Botany 80: 757–762. Download PDF


4. Fritsch, P. W., M. A. Hanson, C. D. Spore, P. E. Pack, and L. H. Rieseberg. 1993. Constancy of RAPD primer amplification strength among distantly related taxa of flowering plants. Plant Molecular Biology Reporter 11: 10–20. Download PDF


5. Fritsch, P. W. 1993. Vascular plant species new to Hillsdale County, Michigan. Michigan Botanist 32: 269–282. Download PDF


6. Fritsch, P. W. and L. H. Rieseberg. 1996. The use of random amplified polymorphic DNA (RAPD) in conservation genetics. In T. Smith and B. Wayne (eds.), Molecular Genetic Approaches in Conservation, pp. 54–73. Oxford Univ. Press, New York.


7. Fritsch, P. W. 1996. Isozyme analysis of intercontinental disjuncts within Styrax (Styracaceae): Implications for the Madrean-Tethyan hypothesis. American Journal of Botany 83: 342–355.


8. Fritsch, P. W. 1996. Population structuring and patterns of morphological variation in the Californian endemic Styrax redivivus. Aliso 14: 205–218.


9. Fritsch, P. W. 1997. A revision of Styrax (Styracaceae) from western Texas, Mexico, and Mesoamerica. Annals of the Missouri Botanical Garden 84: 705–761.


10. Fritsch, P. W. 1999. Phylogeny of Styrax based on morphological characters, with implications for biogeography and infrageneric classification. Systematic Botany 24: 355–378.


11. Fritsch, P. W. 1999. Styracaceae. In P. M. Jørgensen and S. León-Yánez (eds.), Catalogue of the Vascular Plants of Ecuador, p. 922. Missouri Botanical Garden Press, St. Louis.


12. Fritsch, P. W. Styracaceae. 2000. Flora Mesoamericana Volume 4. Universidad Nacional Autónoma de México, México, D. F. Available on-line at


13. Fritsch, P. W. and S. A. Lucas. 2000. Clinal variation in the Halesia carolina complex (Styracaceae). Systematic Botany 25: 197–210.


14. Fritsch, P. W. 2001. Phylogeny and biogeography of the flowering plant genus Styrax (Styracaceae) based on chloroplast DNA restriction sites and DNA sequences of the internal transcribed spacer region. Molecular Phylogenetics and Evolution 19: 387–408.


15. Fritsch, P. W., C. M. Morton, C. T. Chen, and C. Meldrum. 2001. Phylogeny and biogeography of the Styracaceae. International Journal of Plant Sciences 162(S6): S95–S116.


16. Davis, C. C., P. W. Fritsch, J.-H. Li, and M. J. Donoghue. 2002. Phylogeny and biogeography of Cercis (Fabaceae): Evidence from nuclear ribosomal ITS and chloroplast ndhF sequence data. Systematic Botany 27: 298–302.


17. Fritsch, P. W., S. A. Mori, and J. L. Brown. 2002. Styracaceae. In S. A. Mori, G. Cremers, C. A. Gracie, J.-J. de Granville, S. V. Heald, M.Hoff, and J. D. Mitchell (eds.), Guide to the Vascular Plants of Central French Guiana. Part 2. Dicotyledons. Memoirs of the New York Botanical Garden 76(2): 706–708.


18. Davis, C. C., C. D. Bell, P. W. Fritsch, and S. Mathews. 2002. Phylogeny of Acridocarpus-Brachylophon (Malpighiaceae): Implications for Tertiary tropical floras and Afroasian biogeography. Evolution 56: 2395–2405.


19. Fritsch, P. W. and T. D. McDowell. 2003. Biogeography and phylogeny of Caribbean Plants–Introduction. Systematic Botany 28: 376–377. Download PDF


20. Fritsch, P. W. 2003. Multiple geographic origins of Antillean Styrax. Systematic Botany 28: 421–430. Download PDF


21. Huang, Y. L., P. W. Fritsch, and S. Shi. 2003. A revision of the imbricate group of Styrax series Cyrta (Styracaceae) in Asia. Annals of the Missouri Botanical Garden 90: 491–553.


22. Fritsch, P. W. 2003. Styracaceae.  In N. Smith, S. A. Mori, A. Henderson, D. Wm. Stevenson, and S. V. Heald (eds.), Flowering Plants of the Neotropics, pp. 362–363. The New York Botanical Garden and Princeton University Press, Bronx and Princeton.


23. Fritsch, P. W. 2003. Revision of 11 taxa of Styracaceae. In: Gamarra Rojas, C.F.L.; Mesquita, A.C. de; Sothers, C.; Mayo, S.J.; Barbosa, M.R.V. (eds.), Checklist das plantas do Nordeste, Centro Nordestino de informações sobre plantas. CNIP, Recife. Internet publication on website:


24. Fritsch, P. W. 2004. Styracaceae. In: K. Kubitzki (ed.), The Families and Genera of Vascular Plants, pp. 434–442. Springer-Verlag, Berlin.


25. Fritsch, P. W. 2004. New species and taxonomic changes in Styrax (Styracaceae) from South America. Novon 14: 43–57.


26. Fritsch, P. W., F. Almeda, S. S. Renner, A. B. Martins, and B. C. Cruz. 2004. Phylogeny and circumscription of the near-endemic Brazilian tribe Microlicieae (Melastomataceae). American Journal of Botany 91: 1105–1114.


27. Wang, Y., P. W. Fritsch, S. Shi, F. Almeda, B. C. Cruz, and L. M. Kelly. 2004. Phylogeny and infrageneric classification of Symplocos (Symplocaceae) inferred from DNA sequence data. American Journal of Botany 91: 1901–1914.


28. Davis, C. C., P. W. Fritsch, C. D. Bell, and S. Mathews. 2004. High latitude Tertiary migrations of an exclusively tropical clade: Evidence from Malpighiaceae. International Journal of Plant Sciences 165 (4 Suppl.): S107–S121.


29. Qin, H. N. and P. W. Fritsch. 2005. Clethraceae. In: C. Y. Wu and P. H. Raven (eds.), Flora of China, Volume 14: Apiaceae through Ericaceae, pp. 238–241. Science Press, Beijing and Missouri Botanical Garden Press, St. Louis.


30. Aranha Filho, J. L. M., P. W. Fritsch, F. Almeda, and A. B. Martins. 2005. Two new species of Symplocos Jacq. (Symplocaceae) from Minas Gerais, Brazil. Proceedings of the California Academy of Sciences 56: 295–303.


31. Fritsch, P. W. 2005. A new species of Styrax (Styracaceae) from southern Mexico. Novon 15: 421–424.


32. Fritsch, P. W. 2005. Styracaceae. In: T. F. Daniel (ed.), Flora of Chiapas, Part 6, pp. 24–32. California Academy of Sciences, San Francisco.


33. Fritsch, P. W. and J. A. Steyermark. 2005. Styracaceae. In: P. E. Berry, K. Yatskievych, and B. K. Holst (eds.), Flora of the Venezuelan Guayana, Volume 9, pp. 283–289. Missouri Botanical Garden Press, St. Louis.


34. Fritsch, P. W., B. C. Cruz, F. Almeda, Y. Wang, and S. Shi. 2006. Phylogeny of Symplocos based on DNA sequences of the chloroplast trnC-trnD intergenic region. Systematic Botany 31: 181–192.


35. Ji, Y. H., P. W. Fritsch, H. Li, T. J. Xiao, and Z. K. Zhou. 2006. Phylogeny and classification of Paris (Melanthiaceae) inferred from DNA sequence data. Annals of Botany 98: 245256. Download PDF


36. Wang, Y. H., H. He, T. L. Min, L. H. Zhou, and P. W. Fritsch. 2006. The phylogenetic significance of Apterosperma (Theaceae) based on morphological and karyotype characters. Plant Systematics and Evolution 260: 3952.


37. Zhou, L. H., P. W. Fritsch, and B. Bartholomew. 2006. The Symplocaceae of Gaoligong Shan. Proceedings of the California Academy of Sciences, ser. 4, 57: 387431.


38. Fritsch, P. W. In press. Styracaceae. Flora of North America. Oxford University Press, New York.


39. Fritsch, P. W. In press. Styracaceae. In P. M. Jørgensen (ed.), Catalogue of Vascular Plants of Bolivia. Missouri Botanical Garden, St. Louis.


40. Fritsch, P. W. In Press. Styracaceae. In R. Callejas and M. Montiel (eds.), Catalogue of the Vascular Plants of the Department of Antioquia, Colombia. Missouri Botanical Garden Press, St. Louis.


41. Almeda, F., P. W. Fritsch, and J. L. M. Aranha-Filho. In Press. Symplocaceae. In M. Belgrano (ed.), Catalogue of the Vascular Plants of the Southern Cone.


42. Fritsch, P. W. In Press. Styracaceae. In M. Belgrano (ed.), Catalogue of the Vascular Plants of the Southern Cone.


43. Fritsch, P. W. In press. Styracaceae. In B. G. Baldwin et al. (eds.), The Jepson Manual, Higher Plants of California. 2nd Ed. University of California Press, Berkeley, CA.