You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Radiation of the Australian Salicornioideae (Chenopodiaceae): Based on Evidence from Nuclear and Chloroplast DNA Sequences
K. A. Shepherd, M. Waycott and A. Calladine
American Journal of Botany
Vol. 91, No. 9 (Sep., 2004), pp. 1387-1397
Published by: Botanical Society of America, Inc.
Stable URL: http://www.jstor.org/stable/4123936
Page Count: 11
You can always find the topics here!Topics: Genera, Taxa, Biological taxonomies, Botany, Parsimony, Phylogenetics, Hybridity, Plants, Phylogeny, Evolution
Were these topics helpful?See something inaccurate? Let us know!
Select the topics that are inaccurate.
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
In phylogenetic analyses of nuclear ITS and chloroplast trnL DNA sequences, the mostly endemic Australian genera; Halosarcia, Pachycornia, Sclerostegia, Tecticornia, and Tegicornia of the subfamily Salicornioideae (Chenopodiaceae) together form a monophyletic group, congruent with the hypothesis that they evolved from a common ancestor. However, limited genetic differentiation evident in both nrDNA and cpDNA sequences among these taxa suggests a possible rapid radiation. Based on fossil pollen records and climatic models of other authors, it is hypothesized that the expansion of the Australian endemic Salicornioideae most likely occurred during the Late Miocene to Pliocene, when increasing aridity caused the formation of extensive salt lakes along endorheic paleodrainage channels. Moreover, Australian Sarcocornia representatives were supported as monophyletic, nested within a paraphyletic Sarcocornia clade that also comprised European Salicornia in the ITS analysis. This suggests that Sarcocornia arrived in Australia subsequent to the ancestor of the Australian endemic genera most likely via long-distance dispersal.
American Journal of Botany © 2004 Botanical Society of America, Inc.