Farewell to Species - reticulation

[A Mitchell]

Hubert Turner <turner at RULSFB.LEIDENUNIV.NL> wrote:

>Because permanent splits are the only things recognized by a
>cladistic analysis,  in the ideal case (i.e. when no homoplasies
>occur to muddle the outcome of the analysis) the cladogram would
>be:
>
>A   B  C  Z     D
> \   \/   |    /
>  \   \   |   /
>   \   \  |  /
>    \   \ | /
>     \   \|/
>      \   /
>       \ /
>        /
>       /
>

Of course, polytomies do not necessarily indicate hybridization--they more
commonly indicate a lack of data or homoplasy due to
convergence/parallelism.  And that just reinforces my point.  Cladistic
analysis cannot yield anastomosing branches.  Therefore I have to agree
with Thomas Lammers, who started this thread by noting that cladistic
methods assume that "all evolution is dichotomously divergent."

However, I think it's a leap from there to condemning cladistics
generally.


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