Geography Reference
In-Depth Information
Figure 5.13
Three area statement analysis. (a-d) Taxon-area cladograms and
matrices derived from them: (a) trivial case; (b) taxon with a missing area; (c) wide-
spread taxon; (d) taxon with a redundant distribution; (e) data matrix with all the in-
formation; (f) general area cladogram obtained. AF, Africa; AUS, Australia; NA, North
America; SA, South America.
Algorithm
The algorithm consists of the following steps (Nelson and
Ladiges 1991a, 1991c, 1993):
1. Obtain the taxonomic cladograms of the taxa distributed in the areas ana-
lyzed.
2. Replace the terminal taxa from the taxonomic cladograms with the areas
inhabited by them to obtain taxon-area cladograms.
3. Construct a data matrix in which areas are the rows, and components and
widespread terminal species are the columns, coding the relationships as
three area statements. Add a row with all “0” to root the cladogram.
4. Analyzethedatamatrixwithaparsimonyorcompatibilityalgorithminorder
to obtain the general area cladogram.
