Re: Oops, Back to the You Know What

In sci.anthropology.paleo, JAE created a message ID
news:1117008677.401185.231220@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

> There's considerable misuse of cladistics. I'm suspicious
whenever I
> see the line "principles of cladistics." Sounds more
religious. It's
> not a principle so much as it's a methodological approach to
examine
> evolutionary relationships between taxa as these
relationships relate
> to heritable traits. It provides both a methodology for
deducing
> relationships from traits (provided the mechanism of
heredity is solid)
> and, if the relationships are know, for analyzing the
evolution of
> heritable traits over the natural histories of related taxa.

This I like. I haven't seen it put like this before, but you
are absolutely correct. I think in many cases, instead of
assigning a species name the researchers should point out the
methodology they use for determining separate clads and
explain why, for example, if only one fossil of a morphotype
exists, why it deserves a separate species. If other people
are using other criteria and that criteria is not used it
should be explained why.

I was just going over the wheat genetics and if appears that
modern wheat is placed in the genus Triticum

However bread wheat is a hybrid between that genus and
Aegilops.

Emmers GoatGrass Bread Wheat.
AABB + CCDD ----> AABBDD hexaploid wheat (less CC)

CCDD is a hybrid between two species of Aegilops

AA is a hybrid between the ancestor of Einkorn wheat and some
other grass of unknown origin.

Obviously there must be a reason why these are all assigned to
separate genomes, since they can clearly inter mate.

In the other triticeae grains the same process of
hybridization has been used.

There are speltoid goatgrass genes that have made their way
into AABBDD (spelt) and there appears to be an asia precursory
spelt AABB

The basic problem with systematics is that nomenclature and
reality often differ. The assignment of names based on
esoteric qualities such as culture or phenotype should include
a suffix allowing them to remain in a temporary or informal
status until sufficient information is accumulated for
otherwise.

.

Quantcast