Compositional argument for homology

[Doug Yanega]

Claudio Matzke wrote:

>"Compositional relationship between components of an organism may be an
>argument for homologies between parts of organisms."
>
>May anybody understand this sentence?
>
>Thank you for telling me.

This sounds like a loose translation of one of Reaumeur's (sp.? I'm sure
I've got this wrong) rules of homology, for which I don't have the citation
handy, but might be the source - for example, if you are comparing
arthropods with similar numbers of segments/tagmata (components), one can
argue that structures or appendages present in similar places on the same
segment/tagma (a similar compositional relationship between components) are
likely to be homologous. An example would be the homology of the fly
haltere with the metathoracic wings of other insects. I suspect other folks
here can give a cleaner explanation.

Peace,

Doug Yanega    Depto. de Biologia Geral, Instituto de Ciencias Biologicas,
Univ. Fed. de Minas Gerais, Cx.P. 486, 30.161-970 Belo Horizonte, MG   BRAZIL
phone: 031-448-1223, fax: 031-441-5481  (from U.S., prefix 011-55)
                  http://www.icb.ufmg.br/~dyanega/
  "There are some enterprises in which a careful disorderliness
        is the true method" - Herman Melville, Moby Dick, Chap. 82