MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
artículos
Título:
Homology as a parsimony problem: a dynamic homology approach for morphological data
Autor/es:
MARTÍN J. RAMÍREZ
Revista:
CLADISTICS (PRINT)
Editorial:
Blackwell Publishing
Referencias:
Año: 2007 vol. 23 p. 588 - 612
ISSN:
0748-3007
Resumen:
The
primary data used to reconstruct phylogenies comes organized in the conceptual
grid of homology correspondences, and the construction of this theory-rich grid
depends in part on knowledge of relationships. This situation is not
satisfactory as a conceptual system, because the evidence is not clearly
delimited from the results. I explore the testing of alternative hypotheses of
morphological correspondences in a quantitative cladistic context. The varying
homology assessments implied by classical criteria of homology (topological
equivalence, or position and connections; composition of structures, or
commonality in details of construction) can be expressed as regular characters
in a cladistic analysis. Doing so provides adequate transformation costs for changes
in schemas of correspondences. Correspondences imply evolutionary
transformations, and multiple schemas of correspondences can be compared according
to the evolutionary transformations that they imply. The method is used to test
the correspondences in sclerites of the male copulatory organs of spiders of
the subfamily Amaurobioidinae (Arachnida, Araneae, Anyphaenidae). The
correspondences of three sclerites are tested, in a data set of 93 species
having one, two or three sclerites, using a simultaneous analysis of all the morphological
characters. Most parsimonious trees are identified together with the
correspondences they imply. Once the correspondences are integrated in the
phylogenetic analysis, it is easy to evaluate the robustness of trees or decay
in optimality after changes in anatomical interpretations. A Bremer support for
anatomical interpretations is proposed, calculated as the increase in tree
length when the specific interpretation is not used.