Of Trees, nodes, and minimal paths (was Re: Urheimat in Lithuania?)

[Ante Aikio]

On Fri, 31 Mar 2000, Robert Whiting wrote:

> The tree model has
> severe limitations and it is important to be aware of what these
> limitations are.  Perhaps all trees should be required to have
> a warning label something like "WARNING:  This tree does not
> reflect reality except in certain narrow areas.  Do not try to
> apply this tree to real life situations."  or "WARNING:  This
> tree is an abstraction based on limited data.  Prolonged use
> without constant reference to the data may be hazardous to your
> mental health."

It happens all too often that it is not taken into account what a family
tree represents and what it doesn't. As Anthony Fox (Linguistic
Reconstruction, 1995) put rather elegantly, "the wave model simply
provides the means by which languages may split, whereas the tree
represents the result of the split". It is an error to interpret a family
tree as a straightforward depiction of how the languages in reality did
split from each other.

> Even so, the tree model is still useful for certain things so it
> can't really be dispensed with.  And anything that provides a
> better model of the features that the tree doesn't, will probably
> distort the features that are made clear by the tree, as well as
> running the risk of being too complex to be comprehensible (e.g.,
> isogloss maps or dialect geography).

The tree model cannot be dispensed with because it actually is implicit in
the comparative method itself. I can't see how the method could be
practiced without an underlying assumtion of a family tree. But you
of course mean whether it is useful to use the family tree as a tool
for illustrating genetic relationships. I'd say no, unless one constantly
bears in mind the warnings you gave above :) There are some sorry
examples, e.g. the traditional binary family tree of the Uralic
languages. In retrospect, I'd say that it was a hindrance to the progress
of Uralistics, but nevertheless its justification remained unquestioned
for almost 100 years.

Regards,
Ante Aikio