Raymund Chan
Research Associate |
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 Lasthenia ferrisiae West of Livermore, Solano Co.  Lasthenia californica Mori Point, Pacifica, San Mateo Co. |
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My research interests focus on the evolution, phylogeny and biogeography of flowering plants, in particular members of the Compositae. I have worked at several levels: species diversity in California, within geographically restricted and species rich tribes in South Africa, New Guinea, Central and South America, and across continents looking at large scale phylogeny. DNA sequence data, both nuclear and organellar, have proven useful at all of these levels for establishing monophyly, congruence between molecular and non-molecular phylogenies, instances of character evolution, and biogeographic patterns.
Since 2001, I have been working with Dr. Vicki Funk at the Department of Botany, National Museum of Natural History, Smithsonian Institution on an effort directed at clarifying the phylogenetic relationships within the subfamily Cichorioideae especially in the tribes Arctoteae and Liabeae. The Arctoteae is a predominantly South African group (Cape Daisies) comprising ca. 17 genera and 220 species. Our results show that monophyly within the Arctoteae is only weakly supported and that two subtribes are present. The Liabeae is a well-defined neotropical tribe containing ca. 15 genera and 180 species, and occupying a wide variety of habitats throughout Mexico, Central America, the West Indies, and Western South America. We hope that new DNA sequence data will provide some additional information on difficult to place genera and help answer the question of the monophyly of each tribe.
I am also continuing my studies in the tribe Vernonieae. During my postdoctoral studies, I worked with Dr. Sterling Keeley (Department of Botany, University of Hawaii at Manoa) on the molecular systematics of the Vernonieae. This was particularly challenging as there has never been a phylogeny for this tribe and there are over 1500 species distributed worldwide. Our data indicate hemipsherically separate lines except for several New World taxa that group with species from southeast Asia. Resolving these relationships is the next step in this project. We are presently collaborating with Dr. Harold Robinson (Department of Botany, National Museum of Natural History, Smithsonian Institution) to produce a phylogeny incorporating morphological and molecular data.
In my future research I would like to pursue questions of phylogenetic or biogeographic relationships of taxa within the Arctoteae, Liabeae, and Vernonieae in particular and gene evolution within the Compositae in general. I am particularly interested in the evolution of species groups that appear relictual or occupy a critical position within a biogeographically diverse genus. Overall I would like to contribute to a broader understanding of plant evolution.
The goldfield genus Lasthenia. has 17 of its 18 species (21 taxa including subspecies) distributed primarily in the California Floristic Province. All but three taxa are annuals occupying a variety of habitats and are particularly conspicuous in vernal pools. Lasthenia californica is the most common species found in much of cismontane California, extending into southern Oregon, central Arizona, and northern Baja California. In early spring, this species can cover thousands of acres of grasslands and open woodlands with a rich characteristic golden yellow colour thus giving the genus its common name, "goldfields". The only disjunct member of the genus, L. kunthii is found in vernal pools in central Chile.
Seven taxa are listed in the 6th Edition of the California Native Plant Society (CNPS) Inventory of Rare and Endangered Vascular Plants of California. Of these, L. burkei and L. conjugens are listed as endangered by the U.S. Fish and Wildlife Service and/or the California Department of Fish and Game. However, we have found from recent field collections that most species of Lasthenia except for L. californica have rather restricted distributions. Most disturbingly, many of the taxa once reported as common several decades ago are now difficult to locate and relegated to isolated populations growing on private or public lands. Many sites are in danger of being entirely destroyed due to encroachment by agriculture or land development.
Although taxonomically the genus comprises seven sections now, some sections were previously considered as separate genera. Chromosome numbers within the genus were found to be n = 4, 5, 6, 7, 8, 12, 16, 24 suggesting that dysploidy and polyploidy have occurred. These and other phenomena occurring in Lasthenia make this a rather fascinating group to work with. As part of my doctoral dissertation work with Dr. Bruce Baldwin and Dr. Robert Ornduff, we have constructed a plausible phylogeny to try to describe the evolution and diversification of this genus. Using traditional morphological characters, biochemistry, cytology, and molecular sequence data from both nuclear and chloroplast DNA, a cladistic approach has been utilised.
DNA sequence data from the internal (ITS) and external (ETS) transcribed spacers of nuclear ribosomal DNA and the trnK intron of chloroplast DNA show Lasthenia to be a monophyletic group. Overall patterns of divergence in Lasthenia suggest an initial rapid radiation followed by long periods of adaptation and speciation. Results also show that several important taxonomic characters in Lasthenia are homoplastic and that the base chromosome number for Lasthenia is x = 8.
Most intriguingly, we have found that the most common and geographically widespread goldfield species, L. californica actually comprises two distinct taxa. These two taxa can now be distinguished by pappus morphology (although some individuals are epappose) and to some extent by geographic distribution. Previous studies have not been able to detect this cryptic diversity found in populations of L. californica. We have thus updated the taxonomy to recognise these two taxa as L. californica subsp. californica and L. gracilis.
Plants of L. californica subsp. californica have pappi of 1–7, clear to brown, linear to subulate awns and are restricted to southwestern Oregon and northern California (northern Monterey, Santa Clara, Merced, and Madera counties northwards). In contrast, plants of L. gracilis possess pappi of 2–6, usually 4, opaque, white, ovate-lanceolate scales, each tapering to an awn. Lasthenia gracilis also has a wider distribution comprising California, central Arizona, the Channel Islands, Guadalupe Island, and Baja California. In sympatric populations of L. californica subsp. californica and L. gracilis, it is very difficult, if not impossible to distinguish between the two taxa if the plants are epappose.
Epappose plants of L. californica subsp. californica and L. gracilis can be clearly distinguished by using DNA sequence data from the internal transcribed spacer (ITS) region. Lasthenia californica subsp. californica and L. gracilis have different and unique DNA markers as do all Lasthenia taxa.
Lasthenia ornduffii, a new Lasthenia species endemic to Oregon, was named in honour of the late Professor Emeritus Robert Ornduff, a native Oregonian, in appreciation of his outstanding contributions to our understanding of the evolution of Lasthenia and other groups in the California flora.
Funk, V. A., G. Sancho, N. Roque, C. L. Kelloff, I. Ventosa-Rodrigues, M. Diazgranados, J. M. Bonifacino, and R. Chan. 2014. A Phylogeny of the Gochnatieae: Understanding a critically placed tribe in the Compositae. Taxon. 63(4): 859–882.
Robinson, H., S. C. Keeley, J. J. Skvarla, and R. Chan. 2014. Two new genera: Hoffmannanthus and Jeffreycia, mostly from East Africa (Erlangeinae: Vernonieae: Asteraceae). PhytoKeys 39: 49–64.
Funk, V. A., C. Kelloff, and R. Chan. 2012. Phylogeny and biogeography of the tribe Liabeae (Compositae; subfamily Cichoroideae). Taxon 61(2): 437–455.
Chan, R. and R. Ornduff. 2012. Lasthenia. Pp. 364–368. In The Jepson manual: Higher plants of California (2nd Edition). Jepson Flora Project Committee (eds.). University of California Press, Berkeley, California.
Goh, K. M., Y. S. Chua, R. N. Z. R. A. Rahman, R. Chan, and R. M. Illias. 2011. A comparison of conventional and miniprimer PCR to elucidate bacteria diversity in Malaysia Ulu Slim hot spring using a 16S rDNA clone library. Romanian Biotechnological Letters 16(3): 6247–6255.
Funk, V. A. and R. Chan. 2009. Introduction to the Cichorioideae. Pp. 335–342. In Systematics, Evolution, and Biogeography of the Compositae. V. A. Funk, A. Susanna, T. F. Stuessy and R. J. Bayer (eds.). International Association for Plant Taxonomy, Institute of Botany, University of Vienna, Vienna, Austria.
Funk, V. A., ... R. Chan, ... et al. 2009. Compositae meta-supertree: The next generation. Pp. 747–777. In Systematics, Evolution, and Biogeography of the Compositae. V. A. Funk, A. Susanna, T. F. Stuessy and R. J. Bayer (eds.). International Association for Plant Taxonomy, Institute of Botany, University of Vienna, Vienna, Austria.
Dillon, M., V. Funk, H. Robinson, and R. Chan. 2009. Liabeae. Pp. 417–437. In Systematics, Evolution, and Biogeography of the Compositae. V. A. Funk, A. Susanna, T. F. Stuessy and R. J. Bayer (eds.). International Association for Plant Taxonomy, Institute of Botany, University of Vienna, Vienna, Austria.
Karis, P. O., V. A. Funk, R. J. McKenzie, N. P. Barker, and R. Chan. 2009. Arctotideae. Pp. 386–410. In Systematics, Evolution, and Biogeography of the Compositae. V. A. Funk, A. Susanna, T. F. Stuessy and R. J. Bayer (eds.). International Association for Plant Taxonomy, Institute of Botany, University of Vienna, Vienna, Austria.
Funk, V. A. and R. Chan. 2008. Phylogeny of the Spiny African Daisies (Compositae, tribe Arctotideae, subtribe Gorteriinae) based on trnL-F, ndhF, and ITS sequence data. Molecular Phylogenetics & Evolution 48(1): 47–60.
Robinson, H., S. C. Keeley, J. J. Skvarla, and R. Chan. 2008. Studies on the Gymnantheminae (Vernonieae: Asteraceae) III: Restoration of the genus Strobocalyx and the new genus Tarlmounia. Proceedings of the Biological Society of Washington 121(1): 19–33.
Keeley, S., Z. H. Forsman, and R. Chan. 2007. A phylogeny of the “evil tribe” (Vernonieae: Compositae) reveals New/Old World long distance dispersal: Support from separate and combined congruent datasets (ITS, trnL-F, ndhF). Molecular Phylogenetics & Evolution 44(1): 89–103.
Funk, V. A., R. Chan, and A. Holland. 2007. Cymbonotus (Compositae: Arctotideae, Arctotidinae): An endemic Australian genus embedded in a southern African clade. Botanical Journal of the Linnean Society 153(1): 1–8.
Chan, R. and R. Ornduff. 2006. Lasthenia. Pp. 336–347. In Flora of North America North of Mexico, Vol. 21: Asteraceae. Flora of North America Editorial Committee (eds.). Oxford University Press, New York, New York.
Funk, V. A., R. Bayer, S. Keeley, R. Chan, L. Watson, B. Gemeinholzer, E. Schilling, J. Panero, B. Baldwin, N. T. Garcia-Jacas, A. Susanna, and R. K. Jansen. 2005. Everywhere but Antarctica: Using a supertree to understand the diversity and distribution of the Compositae. In Proceedings of a Symposium on Plant Diversity and Complexity Patterns - Local, Regional and Global Dimensions. I. Friis and H. Balslev (eds.). The Royal Danish Academy of Sciences and Letters, Copenhagen. Biologiske Skrifter 55: 343–374. [NMNH Science Achievement Award for Best Paper 2005. Smithsonian Institution]
Funk, V. A., R. Chan, and S. C. Keeley. 2004. Insights into the evolution of the subfamily Cichorioideae sensu stricto and tribe Arctoteae (Compositae) using trnL, ndhF, and ITS sequence data. Taxon 53(3): 637–655.
Chan, R. K.-G. 2004. Occupational health and safety. In Handbook on Responsible Care and Use of Laboratory Animals. Singapore General Hospital.
Rajakaruna, N., B. G. Baldwin, R. Chan, A. M. Desrochers, B. A. Bohm, and J. Whitton. 2003. Edaphic races and phylogenetic species in the Lasthenia californica complex (Asteraceae: Heliantheae): A hypothesis of parallel evolution. Molecular Ecology 12(6): 1675–1679.
Chan, R., B. G. Baldwin, and R. Ornduff. 2002. Cryptic goldfields: A molecular phylogenetic reinvestigation of Lasthenia californica sensu lato and close relatives (Compositae: Heliantheae sensu lato). American Journal of Botany 89(7): 1103–1112.
Chan, R. 2001. A new section in the goldfield genus Lasthenia (Compositae: Heliantheae sensu lato). Madroño 48(1): 38–39.
Chan, R. 2001. Taxonomic changes and a new species in Lasthenia sect. Amphiachaenia (Compositae: Heliantheae sensu lato). Madroño 48(3): 205–210.
Chan, R. 2001. Cover photograph. International Journal of Plant Sciences 162(6).
Chan, R., B. G. Baldwin, and R. Ornduff. 2001. Goldfields revisited: A molecular phylogenetic perspective on the evolution of Lasthenia (Compositae: Heliantheae sensu lato). International Journal of Plant Sciences 162(6): 1347–1360.
Davies, S. J., S. K. Y. Lum, R. Chan, and L. K. Wang. 2001. Evolution of myrmecophytism in Macaranga (Euphorbiaceae). Evolution 55(8): 1542–1559.
Lowrey, T., C. J. Quinn, R. K. Taylor, R. Chan, R. Kimball, and J. C. De Nardi. 2001. A reassessment of relationships within the Vittadinia group of Astereae (Asteraceae). American Journal of Botany 88(7): 1279–1289.
Chan, R. 1999. Plant Diversity Labs (Fungi, Algae, Lower/Higher Plants, Plant Anatomy/Morphology), Chapters 1–4 (Revision). In Biology 1B: Laboratory Manual, 11th edition (and subsequent editions). M. Moser (ed. ). Burgess Publishing Company, Minneapolis, Minnesota.
Mitchell, R., D. Bleakly, R. Cabin, R. Chan, B. Enquist, A. Evans, T. Lowrey, D. Marshall, S. Reed, G. Stevens, and N. Waser. 1993. Species concepts. Nature 364(6432): 20.
Funk, V. A., C. L. Kelloff, and R. Chan. 2012. Systematics and Biogeography of the Liabeae (Compositae): An update. The International Compositae Alliance Meeting, Montreal, 16–18 Jul.
Funk, V. A., G. Sancho, N. Roque, C. L. Kelloff, I. Ventosa-Rodrígues, R. Chan, & M. Bonifacino. 2012. A Phylogeny of the Gochnatieae: Understanding a critically placed tribe in the Compositae. The International Compositae Alliance Meeting, Montreal, 16–18 Jul.
Funk, V. A., C. L. Kelloff, and R. Chan. 2010. Phylogeny and biogeography of the Compositae tribe Liabeae. Annual Meeting of the Botanical Society of America, Providence, Rhode Island, 31 Jul–4 Aug.
Keeley, S. C., V. A. Funk, R. Chan, and Z. H. Forsman. 2007. Long distance dispersal and the position of the Australian taxon Pleurocarpea in the tribe Vernonieae (Compositae). Annual Meeting of the Botanical Society of America, Chicago, Illinois, 7–11 Jul.
Chan, R. and V. A. Funk. 2006. Is the tribe Arctoteae (Compositae: Cichorioideae) monophyletic? More data, more taxa, some answers, even more questions. Centennial Meeting of the Botanical Society of America, Chico, California, 28 Jul–3 Aug. [Paper not delivered due to unforeseen circumstances]
Funk, V. A., ... R. Chan, ... et al. 2006. Evolution of the Compositae based on a new supertree. The International Compositae Alliance Meeting, Barcelona, Spain, 3–10 Jul.
Karis, P. O., V. A. Funk, R. Chan, R. McKenzie, and N. Barker. 2006. Arctotideae: clades, grades, and whereabouts. The International Compositae Alliance Meeting, Barcelona, Spain, 3–10 Jul.
Keeley, S. C., H. Robinson, R. Chan, and Z. Forsman. 2006. Understanding the Vernonieae using molecular and morphological approaches. The International Compositae Alliance Meeting, Barcelona, Spain, 3–10 Jul.
Funk, V. A., R. J. Bayer, S. Keeley, R. Chan, L. Watson, B. Gemeinholzer, E. Schilling, J. L. Panero, B. G. Baldwin, N. Garcia-Jacas, A. Susanna, and R. K. Jansen. 2005. Evolution of the Compositae: The Big Picture. XVII International Botanical Congress, Vienna, Austria, 17–23 Jul.
Karis, P. O., V. Funk, R. Chan, R. McKenzie, and N. Barker. 2005. Small tribes, but a large challenge: Clades and grades of Arctotideae and Liabeae. XVII International Botanical Congress, Vienna, Austria, 17–23 Jul.
Robinson, H., S. Keeley, and R. Chan. 2005. Progress towards a phylogeny of the Vernonieae. XVII International Botanical Congress, Vienna, Austria, 17–23 Jul.
Funk, V. A., and R. Chan. 2004. The importance of outgroup selection and the use of unrooted networks in determining the phylogeny of the tribe Arctoteae (Compositae: subfamily Cichorioideae sensu stricto) using trnL, ndhF, and ITS. Annual meeting of the Botanical Society of America, Snowbird, Utah, 31 Jul–5 Aug.
Funk, V. A., R. J. Bayer, S. Keeley, R. Chan, L. Watson, B. Gemeinholzer, E. Schilling, J. L. Panero, B. G. Baldwin, N. Garcia-Jacas, A. Susanna, and R. K. Jansen. 2004. Using a supertree to understand the diversity and distribution of the Compositae. Annual meeting of the Botanical Society of America, Snowbird, Utah, 31 Jul–5 Aug.
Keeley, S. C., Z. H. Forsman, and R. Chan. 2004. Phylogenetic signal and congruence in nuclear and chloroplast DNA data in the Vernonieae (Asteraceae). Annual meeting of the Botanical Society of America, Snowbird, Utah, 31 Jul–5 Aug.
Funk, V. A., and R. Chan. 2003. Out of Africa: Biogeography of the subfamily Cichorioideae sensu stricto (Compositae). Evolution 2003: Annual joint meeting of the Society for the Study of Evolution, Society of Systematic Biologists, and American Society of Naturalists, Chico, California, 20–24 Jun.
Keeley, S. C., and R. Chan. 2003. Old beginnings and new endings in the biogeography of the Vernonieae (Compositae). Evolution 2003: Annual joint meeting of the Society for the Study of Evolution, Society of Systematic Biologists, and American Society of Naturalists, Chico, California, 20–24 Jun.
Funk, V. A., and R. Chan. 2003. A brief summary of the phylogeny of the Arctoteae (Compositea: Cichorioideae sensu stricto). First International Meeting of Deep Achene: The Compositae Alliance, Pretoria, South Africa, 9–10 Jan. Smithsonian Institution. Compositae Newsletter 40: 13–14.
Keeley, S. C., and R. Chan. 2003. The Vernonieae: Searching for a new paradigm. First International Meeting of Deep Achene: The Compositae Alliance, Pretoria, South Africa, 9–10 Jan. Smithsonian Institution. Compositae Newsletter 40: 19.
Chan, R., B. G. Baldwin, and R. Ornduff. 2001. Cryptic diversity in the goldfield Lasthenia californica sensu lato and close relatives (Compositae: Heliantheae sensu lato). Annual meeting of the Botanical Society of America, Albuquerque, New Mexico, 12–16 Aug.
Davies, S. J., S. K. Y. Lum, R. Chan, and L. K. Wang. 2001. Evolution of myrmecophytism in west Malesian species of Macaranga (Euphorbiaceae). Annual meeting of the Botanical Society of America, Albuquerque, New Mexico, 12–16 Aug.
Lowrey, T. K., C. J. Quinn, R. K. Taylor, R. Chan, R., Kimball, and J. C. De Nardi. 2000. Molecular, morphological, and biogeographical reassessment of relationships within the Vittadinia group of Astereae (Asteraceae). Annual meeting of the Botanical Society of America, Portland, Oregon, 6–10 Aug. American Journal of Botany 87(6 Suppl): 139–140.
Chan, R., T. Lowrey, D. Natvig, R. Kimball, R. Whitkus, and C. Quinn. 1999. Molecular phylogeny of Tetramolopium (Asteraceae). XVI International Botanical Congress, Saint Louis, Missouri, 1–7 Aug.
Chan, R. and R. Ornduff. 1998. Goldfields revisited: Phylogenetic analysis of the genus Lasthenia (Asteraceae) using morphology and DNA sequence data from the nuclear ribosomal ITS and chloroplast trnK intron regions. Annual meeting of the Botanical Society of America, Baltimore, Maryland, 2–6 Aug. American Journal of Botany 85(6 Suppl): 119.
Chan, R., T. Lowrey, D. Natvig, and R. Whitkus. 1995. Phylogenetic analysis of internal transcribed spacer (ITS) sequences from nuclear ribosomal DNA of Hawaiian, Cook Islands, and New Guinea Tetramolopium (Compositae). Annual meeting of the Botanical Society of America, San Diego, California, 6–10 Aug. American Journal of Botany 82(6 Suppl): 118–119.
Lowrey, T., R. Chan, D. Daniels, and R. Whitkus. 1995. Phylogenetic relationships and taxonomic status of Cook Islands Tetramolopium (Compositae) based on artificial hybridization and molecular evidence. Annual meeting of the Botanical Society of America, San Diego, California, 6–10 Aug. American Journal of Botany 82(6 Suppl): 147–148.
Lowrey, T. K., D. Read, R. Chan, and R. Whitkus. 1994. Duplication of cytosolic NADP-IDH in Hawaiian and Cook Islands Tetramolopium. Annual meeting of the Botanical Society of America, Knoxville, Tennessee, 7–11 Aug. American Journal of Botany 81(6 Suppl): 170–171.
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