Lucy in Newsweek

[Curtis Clark]

At 17:46 2004-04-02, HJJACOBSON at AOL.COM wrote:
>I should like to ask a question, and I mean ask. If the "selfish gene" view
>were taken, couldn't DNA be viewed as a parasite? Now studies of parasite and
>host phylogenies show that they are not always congruent. Tree topography and
>rates may differ between parasite and host. Differ enough, I believe, that you
>can't derive one from the other. It isn't always a case of coevolution.

Whether genes are selfish or not, the soma has no other general-purpose way
to transfer information to the next generation. For genes to have
independent histories from their organisms would require that they operate
independently.

>Again,
>assuming the "selfish gene" wouldn't be more conservative to conclude that
>genetic phylogeny isn't necessarily the same as species phylogeny, as John has
>suggested? OK, it's two questions.

Gene trees are *often* not identical to species trees, because of lineage
sorting, polymorphism, and occasional hybridization and lateral transfer.
But that doesn't mean that they don't share the same history. And there is
no more a priori reason to assume that DNA sequences are misleading than
there is to assume that morphology is misleading. The proof has to be in
the analysis.


--
Curtis Clark                  http://www.csupomona.edu/~jcclark/
Web Coordinator, Cal Poly Pomona                 +1 909 979 6371
Professor, Biological Sciences                   +1 909 869 4062