Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support

Comparing the Stratigraphic Record to Estimates of Phylogeny

John P. Huelsenbeck
Paleobiology
Vol. 20, No. 4 (Autumn, 1994), pp. 470-483
Published by: Paleontological Society
Stable URL: http://www.jstor.org/stable/2401230
Page Count: 14
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
Comparing the Stratigraphic Record to Estimates of Phylogeny
Preview not available

Abstract

The age of first occurrence of taxa remains an underutilized source of information in phylogenetic analysis. In this paper I develop a method whereby one can measure the fit of the stratigraphic record to an estimated phylogenetic tree. The method works as follows: (1) each of the internal nodes excluding the root node of a phylogenetic tree is visited, (2) the oldest age of first occurrence for the taxa above the node is compared to the oldest age of first occurrence for the sister node, and (3) if the age above the node is the same age or younger than the age below the node, then the node is stratigraphically consistent. A measure of the total fit of the stratigraphic record to the tree is the proportion of nodes that are stratigraphically consistent (expressed as the stratigraphic consistency index, SCI). This measure of stratigraphic fit is sensitive to errors in phylogenetic estimation as well as to missing lineages (or parts of lineages). The significance of the fit of the stratigraphic record to the tree can be determined through a permutation approach that generates the null distribution for SCI under the hypothesis that the stratigraphic fit is no better than would be expected at random. The method is applied to several studies taken from the literature. Almost all published trees had significant SCI values, meaning the trees fit the stratigraphic record quite well. Applications of stratigraphic consistency for determining the confidence that should be placed in a phylogenetic estimate, for determining the root of a tree, and as a modified optimality criterion for estimating phylogenetic trees are discussed.

Page Thumbnails

  • Thumbnail: Page 
[470]
    [470]
  • Thumbnail: Page 
471
    471
  • Thumbnail: Page 
472
    472
  • Thumbnail: Page 
473
    473
  • Thumbnail: Page 
474
    474
  • Thumbnail: Page 
475
    475
  • Thumbnail: Page 
476
    476
  • Thumbnail: Page 
477
    477
  • Thumbnail: Page 
478
    478
  • Thumbnail: Page 
479
    479
  • Thumbnail: Page 
480
    480
  • Thumbnail: Page 
481
    481
  • Thumbnail: Page 
482
    482
  • Thumbnail: Page 
483
    483