Hostname: page-component-848d4c4894-2xdlg Total loading time: 0 Render date: 2024-06-28T08:04:27.646Z Has data issue: false hasContentIssue false
  • English
  • Français

Morphometric analysis of Rhynia and Asteroxylon: testing functional aspects of early land plant evolution

Published online by Cambridge University Press:  08 February 2016

A. Roth-Nebelsick ,
G. Grimm ,
V. Mosbrugger ,
H. Hass  and
H. Kerp
A. Roth-Nebelsick
Affiliation:
Institut und Museum für Geologie und Paläontologie der Universität Tübingen, Sigwartstr. 10, D-72076 Tübingen, Germany. E-mail: anita.roth@uni-tuebingen.de
G. Grimm
Affiliation:
Institut und Museum für Geologie und Paläontologie der Universität Tübingen, Sigwartstr. 10, D-72076 Tübingen, Germany. E-mail: anita.roth@uni-tuebingen.de
V. Mosbrugger
Affiliation:
Institut und Museum für Geologie und Paläontologie der Universität Tübingen, Sigwartstr. 10, D-72076 Tübingen, Germany. E-mail: anita.roth@uni-tuebingen.de
H. Hass
Affiliation:
7 Abteilung Paläobotanik, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57-59, D-48143 Münster, Germany. E-mail: kerp@uni-muenster.de
H. Kerp
Affiliation:
7 Abteilung Paläobotanik, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57-59, D-48143 Münster, Germany. E-mail: kerp@uni-muenster.de
Get access Rights & Permissions [Opens in a new window]

Abstract

New morphometric data gathered from cross-sections of two Lower Devonian land plants (Rhynia gwynne-vaughanii and Asteroxylon mackiei) are interpreted in terms of the evolution of the function of vascular bundles in early land plants. The following conclusions can be drawn from these new data: (1) The ratio of the cross-sectional area of the xylem (representing the conducting volume supplying the axis with water) to the xylem perimeter (representing the “contact area” between xylem and parenchyma through which water leaves the xylem and enters the parenchyma) is not constant for Rhynia axes, almost constant for Asteroxylon axes, and different between Rhynia and Asteroxylon. Thus, Bowers hypothesis that the ratio of cross-sectional area of the xylem to xylem perimeter is constant during ontogenetic development is true for Asteroxylon. That this ratio is constant during phylogeny, however, is not supported by our data. (2) The ratio between cross-sectional area of xylem to parenchyma is higher in Asteroxylon than in Rhynia. (3) As predicted by previous computer simulations, the ratio of the xylem perimeter to the axis perimeter plays a major role in determining water transport performance of the transpiring axis. This ratio is constant within ontogeny but is different in Asteroxylon and Rhynia. In Asteroxylon axes, this ratio is about twice as large as in Rhynia axes. (4) Contrary to the expectations, the distance between the outermost layer of the xylem and the transpiring surface, which represents the low-conductivity pathway through the parenchyma, appears not to be a limiting factor for the water transport in axes of Rhynia and Asteroxylon. (5) From the analysis of the geometric parameters, it is evident that Rhynia and Asteroxylon with their distinct stelar geometries represent two different constructional types for which no transitional stages are known.

Type
Articles
Information
Paleobiology , Volume 26 , Issue 3 , Summer 2000 , pp. 405 - 418
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Bierhorst, D. W. 1971. Morphology of vascular plants. Macmillan, London.Google Scholar
Bower, F. O. 1908. The origin of the land flora. Macmillan, London.CrossRefGoogle Scholar
Bower, F. O. 1935. Primitive land plants. Macmillan, London.Google Scholar
Edwards, D., and Edwards, D. S. 1986. A reconsideration of the Rhyniophytina banks. In Spicer, R. A. and Thomas, B. A., eds. Systematic and taxonomic approaches in paleobotany. Systematics Association Special Volume 31:199–220. Clarendon, Oxford.Google Scholar
Edwards, D., Davies, K. L., and Axe, L. 1992. A vascular conducting strand in the early land plant Cooksonia. Nature 357:683–685.CrossRefGoogle Scholar
Edwards, D. S. 1980. Evidence for the sporophytic status of the Lower Devonian plant Rhynia gwynne-vaughanii Kidston and Lang. Review of Paleobotany and Palynology 29:177–188.CrossRefGoogle Scholar
Empacher, N., Mosbrugger, V., Roth, A., Wolf, M., and Wunderlin, A. 1995. Qualitative mathematical discussion of different evolutionary states in water transport systems of plants. Journal of Biological Physics 21:241–264.CrossRefGoogle Scholar
Gensel, P. G., and Andrews, H. N. 1984. Plant life in the Devonian., 1st ed.Praeger, New York.Google Scholar
Graham, L. E. 1993. Origin of land plants. Wiley, New York.Google Scholar
Hemsley, A. R. 1992. Vascular pipe dreams. Nature 357:641–642.CrossRefGoogle Scholar
Kenrick, P., and Crane, P. R. 1991. Water-conducting cells in early fossil land plants: implications for the early evolution of tracheophytes. Botanical Gazette 152:335–356.CrossRefGoogle Scholar
Kenrick, P., and Crane, P. R. 1997. The origin and early diversification of land plants: a cladistic study. Smithsonian Institution Press, Washington, D.C.Google Scholar
Kidston, R., and Lang, W. H. 1920a. On old Red Sandstone plants showing structure from the Rhynie chert bed, Aberdeenshire, Part II. Additional notes on Rhynia Gwynne-Vaughani, Kidston and Lang; with descriptions of Rhynia major, n. sp., and Hornea Lignieri, n. g., n. sp. Transactions of the Royal Society of Edinburgh 52:603–627.CrossRefGoogle Scholar
Kidston, R., and Lang, W. H. 1920b. On old Red Sandstone plants showing structure from the Rhynie chert bed, Aberdeenshire, Part III. Asteroxylon Mackiei, Kidston and Lang. Transactions of the Royal Society of Edinburgh 52:643–680.CrossRefGoogle Scholar
Niklas, K. J. 1984. Size-related changes in the primary xylem anatomy of some early tracheophytes. Paleobiology 10:487–506.CrossRefGoogle Scholar
Niklas, K. J. 1997. The evolutionary biology of plants. University of Chicago Press, Chicago.Google Scholar
Proctor, M. C. F. 1979. Structure and eco-physiological adaptation of Bryophytes. Pp. 479–509in Clarke, G. C. S. and Duckett, J. G., eds. Bryophyte systematics. Academic Press, London.Google Scholar
Raven, J. A. 1984. Physiological correlates of the morphology of early vascular plants. Botanical Journal of the Linnean Society 88:105–126.CrossRefGoogle Scholar
Raven, J. A. 1993. The evolution of vascular plants in relation to quantitative functioning of dead water-conducting cells and stomata. Biological Review 68:337–363.CrossRefGoogle Scholar
Roth, A., and Mosbrugger, V. 1996. Numerical studies of water conduction in land plants: evolution of early stele types. Paleobiology 22:411–421.CrossRefGoogle Scholar
Roth, A., Mosbrugger, V., and Neugebauer, H. J. 1994. Efficiency and evolution of water transport systems in higher plants: a modelling approach. II. Stelar evolution. Philosophical Transactions of the Royal Society of London B 345:153–162.Google Scholar
Roth, A., Mosbrugger, V., and Wunderlin, A. 1998. Computer simulations as a tool for understanding the evolution of water transport systems in land plants: a review and new data. Review of Paleobotany and Palynology 102:79–99.CrossRefGoogle Scholar
Speck, T., and Vogellehner, D. 1988. Biophysical examinations of the bending stability of various stele types and the upright axes of early “vascular” plants. Botanica Acta 101:262–268.CrossRefGoogle Scholar
Stein, W. 1993. Modeling the evolution of stelar architecture in vascular plants. International Journal of Plant Science 154:229–263.CrossRefGoogle Scholar
Stewart, W. N., and Rothwell, G. W. 1993. Paleobotany and the evolution of plants, 2d ed. Cambridge University Press, Cambridge.Google Scholar
Taylor, T. N., and Taylor, E. L. 1993. The biology and evolution of fossil plants. Prentice-Hall, Englewood Cliffs, N.J.Google Scholar
Trewin, N. H. 1996. The Rhynie Cherts: an early Devonian ecosystem preserved by hydrothermal activity. Pp. 131–149in Bock, G. R. and Goode, J. A., eds. Evolution of hydrothermal ecosystems on Earth (and Mars?). Ciba Foundation Symposium No. 202. Wiley, Chichester, England.Google Scholar
Zimmermann, W. 1930. Die Phylogenie der Pflanzen. Gustav Fischer, Jena, Germany.Google Scholar