Geography Reference
In-Depth Information
ern and Central Andes (Berry 1982). Morrone and Urtubey (1997) carried out a
cladistic biogeographic analysis of the Northern Andes to explain their biogeo-
graphic history and to determine whether they represent a natural biogeographic
unit.
On the basis of the distribution of the species analyzed, seven areas of
endemism were identified (
fig. 5.19a
)
: A-D, in the Northern Andes, and E-G, “ex-
ternal areas” from the Central Andes. The taxa analyzed were five weevil gen-
era (Coleoptera: Curculionidae) and the plant genus
Barnadesia
(Asteraceae).
Paralogy-free subtrees were obtained with program TASS (Nelson and Ladiges
1995), and two data matrices were built, one based on assumption 2 and another
for BPA. Data matrices were analyzed with Hennig86 version 1.5 (Farris 1988).
Application of TASS to the six original taxon-area cladograms (
figs.
the matrix of paralogy-free subtrees led to three general area cladograms whose
strict consensus has the same topology as one of them (
fig. 5.19h
). The analysis
of the BPA matrix resulted in four general area cladograms; their consensus (
fig.
5.19i
) showed different relationships. The difference between both results may be
due to paralogy.