Abstract Detail

Ericaceae: Systematics, Ecology and Evolution

Liu, Zhenwen [1], Zhou, Jing [2], Peng, Hua [3], Freudenstein, John [4], Milne, Richard [5].

Biogeography of Chimaphila (Ericaceae: Pyroloideae).

Chimaphila comprises five species of boreal-temperate herbs that occur in woodlands from Mexico to Canada in North America and across northern Eurasia and in China.  Chimaphila umbellata is circumboreal, whereas the remainder of species are confined to more limited areas.  The species show distributions consistent with the Arcto-Tertiary and Circumboreal flora patterns, and thus allow us to predict relative ages for groups within the genus and to investigate both biogeographic patterns in a single analysis.  A dataset comprising multiple accessions of each species from across their ranges and sequence data from four plastid regions and nuclear ITS was assembled, aligned and analyzed using maximum likelihood and Bayesian inference.   The tree was dated using calibration points derived from a previous, broader study of subfamily Pyroloideae that contained fossils.  The resulting calibrated tree is well-supported and shows the accessions from each species to form an exclusive group.  Chimaphila has a mean divergence date from Moneses, its sister genus, of 28 MYA. The circumboreal C. umbellata is dated to 6.6 MYA, while its sister group (C. monticola, C. maculata, C. menziesii, C. japonica) diverged at 14.2 MYA.  The biogeographic pattern can be explained by an origin in North America, followed by divergence of C. umbellata from the remainder of the species, with subsequent, relatively recent (ca. 1.9 MYA) dispersal to Eurasia.  The other four species’ distribution pattern represents Arcto-Tertiary transitions from North America to Asia, requiring two events.  Included among these is a trans-Beringian relationship between C. menziesii and C. japonica, with a divergence dated to ca. 6.5 MYA.  These results are consistent with an older origin for species with an Arcto-Tertiary distribution as opposed to the more recent circumboreal pattern.

1 - Kunming Institute Of Botany, Chinese Academy Of Sciences, Key Laboratory Of Plant Diversity And Biogeography Of East Asia, Lanhei Road #132, Kunming, 650201, China
2 - Kunming Medical University, School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming, 650500, China
3 - Kunming Institute Of Botany, Chinese Academy Of Sciences, Key Laboratory Of Plant Diversity And Biogeography Of East Asia, Kunming, 650201, China
4 - Ohio State University Herbaium, Dept. of Evolution, Ecology and Organismal Biology, 1315 Kinnear Road, Columbus, OH, 43212, USA
5 - University of Edinburgh, Institute of Molecular Plant Sciences, School of Biological Sciences, Edinburgh, EH9 3JH, UK


Presentation Type: Colloquium Presentations
Abstract ID:987
Candidate for Awards:None

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