families

[Thomas Schlemmermeyer]

>
>As an additional thought to this interesting topic and as a tentative to
>clarify the concept of selection in the case of higher taxa:
>
>Selection acts, by definition, on gene frequencies.
>
>If a whole family were submitted to selection, this would mean that selection
>pressures worked on the gene frequencies in the whole family.
>
>When could such a miracle happen?
>
>Prior to adaptive radiation in broad scale and diversification of the family.
>
>I presume that the families in discussion are natural families, i.e. families
>which can be traced back to single lineages.
>(To discuss about other than natural families may be intelectually amusing but
>should not be main scope of this list).
>
>It follows, that, probabilistically speaking, the most probable point in
>phylogeny where family selection happens, is at the root of the phylogeny,
>prior to its cladogenesis.
>
>This is all pretty fine theology, the next problem would be to find the exact
>root........
>
>
>      Cheers    Thomas
>

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Thomas Schlemmermeyer
Museu de Zoologia, Universidade de Sco Paulo
Caixa Postal 42694
CEP 04299-970
Sco Paulo, SP, Brasil