Independent lineages

[Pierre Deleporte]

A 17:07 19/04/00 -0700, Jenny Qiu-Yun Xiang wrote :

>Can anyone explain the following concepts to me?
>
>"independent lineages"
>"non-independence due to common ancestry"
>
>Are sister lineages considered "independent lineages"?


Under the assumption of monogenism, no one lineage or clade is
"independent" as for common ancestry. By the way, this is why phylogeny is
reconstructible.

Many times people use to talk about taxa when they should talk about
character states. In two sister-lineages (obviously linked by exclusive
common ancestry), some characters may evolve an independent way, provided
that we assume that "history is unique" for the evolution of characters:
they may change some way in one lineage, some other way in the other
lineage. By the way, this is also why phylogeny is reconstructible.

Pierre



Pierre Deleporte
CNRS UMR 6552 - Station Biologique de Paimpont
F-35380 Paimpont   FRANCE
Téléphone : 02 99 61 81 66
Télécopie : 02 99 61 81 88