Molecular Biology and Evolution, Vol 15, 1189-1194, Copyright © 1998 by Society for Molecular Biology and Evolution
H Wada
Whether the ancestral chordates were free-swimming or sessile is a
longstanding question that remains to be settled. Vertebrates and amphioxi
are free-swimming, but the most basal chordate subphylum (the urochordates)
includes both sessile and free-swimming species. Here, 1 report molecular
phylogenetic analyses of 18S rDNA of urochordates to deduce which lifestyle
is ancestral. This revealed a close relationship between salps and
doliolids and paraphyly of the ascidians. An early divergence of
larvaceans, which show a tadpole-like body plan throughout life, is also
supported by the analyses. Based on this phylogeny, a free-swimming
ancestor for chordates is more parsimonious than a sessile ancestor. The
evolutionary history of various lifestyles of chordates from this ancestral
form is proposed.
ORIGINAL ARTICLE
Evolutionary history of free-swimming and sessile lifestyles in urochordates as deduced from 18S rDNA molecular phylogeny
School of Animal and Microbial Sciences, University of Reading Whiteknights, England. hwada@seto.kyoto-u.ac.jp
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  T. Stach, J. Winter, J.-M. Bouquet, D. Chourrout, and R. Schnabel Embryology of a planktonic tunicate reveals traces of sessility PNAS, May 20, 2008; 105(20): 7229 - 7234. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. M. Soviknes and J. C. Glover Continued Growth and Cell Proliferation Into Adulthood in the Notochord of the Appendicularian Oikopleura dioica Biol. Bull., February 1, 2008; 214(1): 17 - 28. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Hudson and H. Yasuo A signalling relay involving Nodal and Delta ligands acts during secondary notochord induction in Ciona embryos Development, August 1, 2006; 133(15): 2855 - 2864. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Zeng, M. W. Jacobs, and B. J. Swalla Coloniality has evolved once in Stolidobranch Ascidians Integr. Comp. Biol., June 1, 2006; 46(3): 255 - 268. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. L. Cleto, A. E. Vandenberghe, D. W. MacLean, P. Pannunzio, C. Tortorelli, T. H. Meedel, Y. Satou, N. Satoh, and K. E. M. Hastings Ascidian Larva Reveals Ancient Origin of Vertebrate-Skeletal-Muscle Troponin I Characteristics in Chordate Locomotory Muscle Mol. Biol. Evol., December 1, 2003; 20(12): 2113 - 2122. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. S. Monteiro, B. Okamura, and P. W. H. Holland Orphan Worm Finds a Home: Buddenbrockia is a Myxozoan Mol. Biol. Evol., June 1, 2002; 19(6): 968 - 971. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. J. Winchell, J. Sullivan, C. B. Cameron, B. J. Swalla, and J. Mallatt Evaluating Hypotheses of Deuterostome Phylogeny and Chordate Evolution with New LSU and SSU Ribosomal DNA Data Mol. Biol. Evol., May 1, 2002; 19(5): 762 - 776. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. F. Hinman and B. M. Degnan Homeobox Genes, Retinoic Acid and the Development and Evolution of Dual Body Plans in the Ascidian Herdmania curvata Integr. Comp. Biol., June 1, 2001; 41(3): 664 - 675. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. B. Cameron, J. R. Garey, and B. J. Swalla Special Feature: Evolution of the chordate body plan: New insights from phylogenetic analyses of deuterostome phyla PNAS, April 25, 2000; 97(9): 4469 - 4474. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R Eri, J. Arnold, V. Hinman, K. Green, M. Jones, B. Degnan, and M. Lavin Hemps, a novel EGF-like protein, plays a central role in ascidian metamorphosis Development, January 12, 1999; 126(24): 5809 - 5818. [Abstract] [PDF]
|
|