|
|
||||||||
Systematics |
Department of Botany, University of Wisconsin, 430 Lincoln Drive, Madison, Wisconsin 53706 USA
Banksia and Dryandra have undergone extensive speciation and adaptive radiation, especially in Australia's isolated Southwest Botanical Province. We derive a phylogeny for these groups based on cpDNA sequences and use it to reconstruct their historical biogeography and evolution of leaf traits thought to be adapted to drought and/or nutrient poverty. Slowly evolving regions (trnL intron, trnL/trnF spacer) are used to resolve large-scale relationships; faster evolving regions (rp116 intron, psbA/trnH and trnT/trnL spacers) are used to resolve relationships among closely related species. Banksia is paraphyletic with respect to Dryandra. The lineage underwent a basal split into two clades (here named /Cryptostomata and /Phanerostomata), and four infrageneric taxa supported by morphological cladistic analyses (series Spicigerae, Abietinae, Tetragonae, and Banksia) are not monophyletic. Dispersal-vicariance analysis resolves a southwestern Australian origin for the lineage, with two later expansions to the east followed by vicariance events. Stomatal crypts arose with the /Cryptostomata, which is characterized by tough, long-lived leaves and common in southwestern Australia. Sequestering of stomata also arose multiple times in /Phanerostomata, which is characterized by softer, short-lived leaves and common in moister coastal areas, via inrolling of the margins of narrow leaves and restricting stomata to shallow pits. The hypothesis that sclerophylly preadapted the plants to xeromorphy is supported in the case of shallow stomatal pits and deep stomatal crypts, but not narrow, needle-like leaves.
Key Words: Australia's Southwest Botanical Province Banksia Dryandra historical biogeography molecular systematics preadaptation sclerophylly xeromorphy
This article has been cited by other articles:
![]() |
A. R. Mast, C. L. Willis, E. H. Jones, K. M. Downs, and P. H. Weston A smaller Macadamia from a more vagile tribe: inference of phylogenetic relationships, divergence times, and diaspore evolution in Macadamia and relatives (tribe Macadamieae; Proteaceae) Am. J. Botany, July 1, 2008; 95(7): 843 - 870. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. J. Jordan, P. H. Weston, R. J. Carpenter, R. A. Dillon, and T. J. Brodribb The evolutionary relations of sunken, covered, and encrypted stomata to dry habitats in Proteaceae Am. J. Botany, May 1, 2008; 95(5): 521 - 530. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. M. Crayn, M. Rossetto, and D. J. Maynard Molecular phylogeny and dating reveals an Oligo-Miocene radiation of dry-adapted shrubs (former Tremandraceae) from rainforest tree progenitors (Elaeocarpaceae) in Australia Am. J. Botany, September 1, 2006; 93(9): 1328 - 1342. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Lesica, R. Yurkewycz, and E. E Crone Rare plants are common where you find them Am. J. Botany, March 1, 2006; 93(3): 454 - 459. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. J. Kress, K. J. Wurdack, E. A. Zimmer, L. A. Weigt, and D. H. Janzen Use of DNA barcodes to identify flowering plants PNAS, June 7, 2005; 102(23): 8369 - 8374. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. J. Jordan, R. A. Dillon, and P. H. Weston Solar radiation as a factor in the evolution of scleromorphic leaf anatomy in Proteaceae Am. J. Botany, May 1, 2005; 92(5): 789 - 796. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Shaw, E. B. Lickey, J. T. Beck, S. B. Farmer, W. Liu, J. Miller, K. C. Siripun, C. T. Winder, E. E. Schilling, and R. L. Small The tortoise and the hare II: relative utility of 21 noncoding chloroplast DNA sequences for phylogenetic analysis Am. J. Botany, January 1, 2005; 92(1): 142 - 166. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |